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authorKartik K. Agaram <vc@akkartik.com>2016-09-17 18:03:26 -0700
committerKartik K. Agaram <vc@akkartik.com>2016-09-17 18:03:26 -0700
commitcebb5fca612321f9436f324d6b95e94b0f1ac614 (patch)
treebc6c4f0e659990da24c019cdaefef4d9cb3ac2b1
parent2d91279bacda12ea42608b4aa74f66589772fce9 (diff)
downloadmu-cebb5fca612321f9436f324d6b95e94b0f1ac614.tar.gz
3397
-rw-r--r--html/edit/001-editor.mu.html22
-rw-r--r--html/edit/002-typing.mu.html196
-rw-r--r--html/edit/003-shortcuts.mu.html570
-rw-r--r--html/edit/004-programming-environment.mu.html94
-rw-r--r--html/edit/005-sandbox.mu.html146
-rw-r--r--html/edit/006-sandbox-copy.mu.html48
-rw-r--r--html/edit/007-sandbox-delete.mu.html58
-rw-r--r--html/edit/008-sandbox-edit.mu.html52
-rw-r--r--html/edit/009-sandbox-test.mu.html22
-rw-r--r--html/edit/010-sandbox-trace.mu.html32
-rw-r--r--html/edit/011-errors.mu.html82
-rw-r--r--html/edit/012-editor-undo.mu.html510
12 files changed, 916 insertions, 916 deletions
diff --git a/html/edit/001-editor.mu.html b/html/edit/001-editor.mu.html
index b61e405d..a5b87d06 100644
--- a/html/edit/001-editor.mu.html
+++ b/html/edit/001-editor.mu.html
@@ -62,7 +62,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   ]
 ]
 
-<span class="muData">container</span> editor-data [
+<span class="muData">container</span> editor [
   <span class="Comment"># editable text: doubly linked list of characters (head contains a special sentinel)</span>
   data:&amp;:duplex-list:char
   top-of-screen:&amp;:duplex-list:char
@@ -83,12 +83,12 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="Comment"># creates a new editor widget and renders its initial appearance to screen</span>
 <span class="Comment">#   top/left/right constrain the screen area available to the new editor</span>
 <span class="Comment">#   right is exclusive</span>
-<span class="muRecipe">def</span> new-editor s:text, screen:&amp;:screen, left:num, right:num<span class="muRecipe"> -&gt; </span>result:&amp;:editor-data, screen:&amp;:screen [
+<span class="muRecipe">def</span> new-editor s:text, screen:&amp;:screen, left:num, right:num<span class="muRecipe"> -&gt; </span>result:&amp;:editor, screen:&amp;:screen [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   <span class="Comment"># no clipping of bounds</span>
   right<span class="Special"> &lt;- </span>subtract right, <span class="Constant">1</span>
-  result<span class="Special"> &lt;- </span>new <span class="Constant">editor-data:type</span>
+  result<span class="Special"> &lt;- </span>new <span class="Constant">editor:type</span>
   <span class="Comment"># initialize screen-related fields</span>
   *result<span class="Special"> &lt;- </span>put *result, <span class="Constant">left:offset</span>, left
   *result<span class="Special"> &lt;- </span>put *result, <span class="Constant">right:offset</span>, right
@@ -106,7 +106,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="Constant">  &lt;editor-initialization&gt;</span>
 ]
 
-<span class="muRecipe">def</span> insert-text editor:&amp;:editor-data, text:text<span class="muRecipe"> -&gt; </span>editor:&amp;:editor-data [
+<span class="muRecipe">def</span> insert-text editor:&amp;:editor, text:text<span class="muRecipe"> -&gt; </span>editor:&amp;:editor [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   <span class="Comment"># early exit if text is empty</span>
@@ -132,8 +132,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="muScenario">scenario</span> editor-initializes-without-data [
   assume-screen <span class="Constant">5/width</span>, <span class="Constant">3/height</span>
   run [
-    <span class="Constant">1</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">0/data</span>, screen:&amp;:screen, <span class="Constant">2/left</span>, <span class="Constant">5/right</span>
-    <span class="Constant">2</span>:editor-data<span class="Special"> &lt;- </span>copy *<span class="Constant">1</span>:&amp;:editor-data
+    <span class="Constant">1</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">0/data</span>, screen:&amp;:screen, <span class="Constant">2/left</span>, <span class="Constant">5/right</span>
+    <span class="Constant">2</span>:editor<span class="Special"> &lt;- </span>copy *<span class="Constant">1</span>:&amp;:editor
   ]
   memory-should-contain [
     <span class="Comment"># 2 (data) &lt;- just the § sentinel</span>
@@ -156,7 +156,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="Comment"># Assumes cursor should be at coordinates (cursor-row, cursor-column) and</span>
 <span class="Comment"># updates before-cursor to match. Might also move coordinates if they're</span>
 <span class="Comment"># outside text.</span>
-<span class="muRecipe">def</span> render screen:&amp;:screen, editor:&amp;:editor-data<span class="muRecipe"> -&gt; </span>last-row:num, last-column:num, screen:&amp;:screen, editor:&amp;:editor-data [
+<span class="muRecipe">def</span> render screen:&amp;:screen, editor:&amp;:editor<span class="muRecipe"> -&gt; </span>last-row:num, last-column:num, screen:&amp;:screen, editor:&amp;:editor [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   <span class="muControl">return-unless</span> editor, <span class="Constant">1/top</span>, <span class="Constant">0/left</span>, screen/same-as-ingredient:<span class="Constant">0</span>, editor/same-as-ingredient:<span class="Constant">1</span>
@@ -181,7 +181,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     <span class="muControl">break-unless</span> curr
     off-screen?:bool<span class="Special"> &lt;- </span>greater-or-equal row, screen-height
     <span class="muControl">break-if</span> off-screen?
-    <span class="Comment"># update editor-data.before-cursor</span>
+    <span class="Comment"># update editor.before-cursor</span>
     <span class="Comment"># Doing so at the start of each iteration ensures it stays one step behind</span>
     <span class="Comment"># the current character.</span>
     <span class="Delimiter">{</span>
@@ -378,9 +378,9 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   assume-screen <span class="Constant">5/width</span>, <span class="Constant">5/height</span>
   run [
     <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[]</span>
-    <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   screen-should-contain [
    <span class="Constant"> .     .</span>
diff --git a/html/edit/002-typing.mu.html b/html/edit/002-typing.mu.html
index 815f5fab..469acd95 100644
--- a/html/edit/002-typing.mu.html
+++ b/html/edit/002-typing.mu.html
@@ -41,12 +41,12 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   open-console
-  editor:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor text, <span class="Constant">0/screen</span>, <span class="Constant">5/left</span>, <span class="Constant">45/right</span>
+  editor:&amp;:editor<span class="Special"> &lt;- </span>new-editor text, <span class="Constant">0/screen</span>, <span class="Constant">5/left</span>, <span class="Constant">45/right</span>
   editor-event-loop <span class="Constant">0/screen</span>, <span class="Constant">0/console</span>, editor
   close-console
 ]
 
-<span class="muRecipe">def</span> editor-event-loop screen:&amp;:screen, console:&amp;:console, editor:&amp;:editor-data<span class="muRecipe"> -&gt; </span>screen:&amp;:screen, console:&amp;:console, editor:&amp;:editor-data [
+<span class="muRecipe">def</span> editor-event-loop screen:&amp;:screen, console:&amp;:console, editor:&amp;:editor<span class="muRecipe"> -&gt; </span>screen:&amp;:screen, console:&amp;:console, editor:&amp;:editor [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   <span class="Delimiter">{</span>
@@ -80,7 +80,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 ]
 
 <span class="Comment"># process click, return if it was on current editor</span>
-<span class="muRecipe">def</span> move-cursor-in-editor screen:&amp;:screen, editor:&amp;:editor-data, t:touch-event<span class="muRecipe"> -&gt; </span>in-focus?:bool, editor:&amp;:editor-data [
+<span class="muRecipe">def</span> move-cursor-in-editor screen:&amp;:screen, editor:&amp;:editor, t:touch-event<span class="muRecipe"> -&gt; </span>in-focus?:bool, editor:&amp;:editor [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   <span class="muControl">return-unless</span> editor, <span class="Constant">0/false</span>
@@ -105,7 +105,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="Comment"># Variant of 'render' that only moves the cursor (coordinates and</span>
 <span class="Comment"># before-cursor). If it's past the end of a line, it 'slides' it left. If it's</span>
 <span class="Comment"># past the last line it positions at end of last line.</span>
-<span class="muRecipe">def</span> snap-cursor screen:&amp;:screen, editor:&amp;:editor-data, target-row:num, target-column:num<span class="muRecipe"> -&gt; </span>editor:&amp;:editor-data [
+<span class="muRecipe">def</span> snap-cursor screen:&amp;:screen, editor:&amp;:editor, target-row:num, target-column:num<span class="muRecipe"> -&gt; </span>editor:&amp;:editor [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   <span class="muControl">return-unless</span> editor
@@ -128,7 +128,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     <span class="muControl">break-unless</span> curr
     off-screen?:bool<span class="Special"> &lt;- </span>greater-or-equal row, screen-height
     <span class="muControl">break-if</span> off-screen?
-    <span class="Comment"># update editor-data.before-cursor</span>
+    <span class="Comment"># update editor.before-cursor</span>
     <span class="Comment"># Doing so at the start of each iteration ensures it stays one step behind</span>
     <span class="Comment"># the current character.</span>
     <span class="Delimiter">{</span>
@@ -196,7 +196,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 
 <span class="Comment"># Process an event 'e' and try to minimally update the screen.</span>
 <span class="Comment"># Set 'go-render?' to true to indicate the caller must perform a non-minimal update.</span>
-<span class="muRecipe">def</span> handle-keyboard-event screen:&amp;:screen, editor:&amp;:editor-data, e:event<span class="muRecipe"> -&gt; </span>screen:&amp;:screen, editor:&amp;:editor-data, go-render?:bool [
+<span class="muRecipe">def</span> handle-keyboard-event screen:&amp;:screen, editor:&amp;:editor, e:event<span class="muRecipe"> -&gt; </span>screen:&amp;:screen, editor:&amp;:editor, go-render?:bool [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   go-render?<span class="Special"> &lt;- </span>copy <span class="Constant">0/false</span>
@@ -236,7 +236,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="muControl">return</span>
 ]
 
-<span class="muRecipe">def</span> insert-at-cursor editor:&amp;:editor-data, c:char, screen:&amp;:screen<span class="muRecipe"> -&gt; </span>editor:&amp;:editor-data, screen:&amp;:screen, go-render?:bool [
+<span class="muRecipe">def</span> insert-at-cursor editor:&amp;:editor, c:char, screen:&amp;:screen<span class="muRecipe"> -&gt; </span>editor:&amp;:editor, screen:&amp;:screen, go-render?:bool [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   before-cursor:&amp;:duplex-list:char<span class="Special"> &lt;- </span>get *editor, <span class="Constant">before-cursor:offset</span>
@@ -302,7 +302,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 ]
 
 <span class="Comment"># helper for tests</span>
-<span class="muRecipe">def</span> editor-render screen:&amp;:screen, editor:&amp;:editor-data<span class="muRecipe"> -&gt; </span>screen:&amp;:screen, editor:&amp;:editor-data [
+<span class="muRecipe">def</span> editor-render screen:&amp;:screen, editor:&amp;:editor<span class="muRecipe"> -&gt; </span>screen:&amp;:screen, editor:&amp;:editor [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   left:num<span class="Special"> &lt;- </span>get *editor, <span class="Constant">left:offset</span>
@@ -318,11 +318,11 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="muScenario">scenario</span> editor-handles-empty-event-queue [
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
   assume-console <span class="Constant">[]</span>
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -335,16 +335,16 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="muScenario">scenario</span> editor-handles-mouse-clicks [
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
 <span class="Constant">  $clear-trace</span>
   assume-console [
     left-click <span class="Constant">1</span>, <span class="Constant">1</span>  <span class="Comment"># on the 'b'</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -362,15 +362,15 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="muScenario">scenario</span> editor-handles-mouse-clicks-outside-text [
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
 <span class="Constant">  $clear-trace</span>
   assume-console [
     left-click <span class="Constant">1</span>, <span class="Constant">7</span>  <span class="Comment"># last line, to the right of text</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   memory-should-contain [
     <span class="Constant">3</span><span class="Special"> &lt;- </span><span class="Constant">1</span>  <span class="Comment"># cursor row</span>
@@ -383,15 +383,15 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc</span>
 <span class="Constant">def]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
 <span class="Constant">  $clear-trace</span>
   assume-console [
     left-click <span class="Constant">1</span>, <span class="Constant">7</span>  <span class="Comment"># interior line, to the right of text</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   memory-should-contain [
     <span class="Constant">3</span><span class="Special"> &lt;- </span><span class="Constant">1</span>  <span class="Comment"># cursor row</span>
@@ -404,15 +404,15 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc</span>
 <span class="Constant">def]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
 <span class="Constant">  $clear-trace</span>
   assume-console [
     left-click <span class="Constant">3</span>, <span class="Constant">7</span>  <span class="Comment"># below text</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   memory-should-contain [
     <span class="Constant">3</span><span class="Special"> &lt;- </span><span class="Constant">2</span>  <span class="Comment"># cursor row</span>
@@ -425,17 +425,17 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc]</span>
   <span class="Comment"># editor occupies only left half of screen</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
 <span class="Constant">  $clear-trace</span>
   assume-console [
     <span class="Comment"># click on right half of screen</span>
     left-click <span class="Constant">3</span>, <span class="Constant">8</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -453,17 +453,17 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="muScenario">scenario</span> editor-handles-mouse-clicks-in-menu-area [
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
 <span class="Constant">  $clear-trace</span>
   assume-console [
     <span class="Comment"># click on first, 'menu' row</span>
     left-click <span class="Constant">0</span>, <span class="Constant">3</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   <span class="Comment"># no change to cursor</span>
   memory-should-contain [
@@ -475,14 +475,14 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="muScenario">scenario</span> editor-inserts-characters-into-empty-editor [
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
 <span class="Constant">  $clear-trace</span>
   assume-console [
     type <span class="Constant">[abc]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -496,8 +496,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="muScenario">scenario</span> editor-inserts-characters-at-cursor [
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
 <span class="Constant">  $clear-trace</span>
   <span class="Comment"># type two letters at different places</span>
   assume-console [
@@ -506,7 +506,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     type <span class="Constant">[d]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -520,15 +520,15 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="muScenario">scenario</span> editor-inserts-characters-at-cursor-2 [
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
 <span class="Constant">  $clear-trace</span>
   assume-console [
     left-click <span class="Constant">1</span>, <span class="Constant">5</span>  <span class="Comment"># right of last line</span>
     type <span class="Constant">[d]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -543,15 +543,15 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc</span>
 <span class="Constant">d]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
 <span class="Constant">  $clear-trace</span>
   assume-console [
     left-click <span class="Constant">1</span>, <span class="Constant">5</span>  <span class="Comment"># right of non-last line</span>
     type <span class="Constant">[e]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -566,15 +566,15 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="muScenario">scenario</span> editor-inserts-characters-at-cursor-3 [
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
 <span class="Constant">  $clear-trace</span>
   assume-console [
     left-click <span class="Constant">3</span>, <span class="Constant">5</span>  <span class="Comment"># below all text</span>
     type <span class="Constant">[d]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -589,15 +589,15 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc</span>
 <span class="Constant">d]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
 <span class="Constant">  $clear-trace</span>
   assume-console [
     left-click <span class="Constant">3</span>, <span class="Constant">5</span>  <span class="Comment"># below all text</span>
     type <span class="Constant">[e]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -613,15 +613,15 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc</span>
 <span class="Constant">d]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
 <span class="Constant">  $clear-trace</span>
   assume-console [
     left-click <span class="Constant">3</span>, <span class="Constant">5</span>  <span class="Comment"># below all text</span>
     type <span class="Constant">[ef]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -636,13 +636,13 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="muScenario">scenario</span> editor-moves-cursor-after-inserting-characters [
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[ab]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
   assume-console [
     type <span class="Constant">[01]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -657,14 +657,14 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="muScenario">scenario</span> editor-wraps-line-on-insert [
   assume-screen <span class="Constant">5/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
   <span class="Comment"># type a letter</span>
   assume-console [
     type <span class="Constant">[e]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># no wrap yet</span>
   screen-should-contain [
@@ -679,7 +679,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     type <span class="Constant">[f]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># now wrap</span>
   screen-should-contain [
@@ -696,17 +696,17 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abcdefg</span>
 <span class="Constant">defg]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
   <span class="Comment"># type more text at the start</span>
   assume-console [
     left-click <span class="Constant">3</span>, <span class="Constant">0</span>
     type <span class="Constant">[abc]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   <span class="Comment"># cursor is not wrapped</span>
   memory-should-contain [
@@ -777,15 +777,15 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="muScenario">scenario</span> editor-wraps-cursor-after-inserting-characters-in-middle-of-line [
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abcde]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
   assume-console [
     left-click <span class="Constant">1</span>, <span class="Constant">3</span>  <span class="Comment"># right before the wrap icon</span>
     type <span class="Constant">[f]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -806,7 +806,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Comment"># create an editor containing two lines</span>
   contents:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc</span>
 <span class="Constant">xyz]</span>
-  <span class="Constant">1</span>:&amp;:editor-data/<span class="Special">raw &lt;- </span>new-editor contents, screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
+  <span class="Constant">1</span>:&amp;:editor/<span class="Special">raw &lt;- </span>new-editor contents, screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
   screen-should-contain [
    <span class="Constant"> .          .</span>
    <span class="Constant"> .abc       .</span>
@@ -818,7 +818,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     type <span class="Constant">[de]</span>  <span class="Comment"># trigger wrap</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">1</span>:&amp;:editor-data/<span class="Special">raw</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">1</span>:&amp;:editor/<span class="Special">raw</span>
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -832,15 +832,15 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="muScenario">scenario</span> editor-wraps-cursor-to-left-margin [
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abcde]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">2/left</span>, <span class="Constant">7/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">2/left</span>, <span class="Constant">7/right</span>
   assume-console [
     left-click <span class="Constant">1</span>, <span class="Constant">5</span>  <span class="Comment"># line is full; no wrap icon yet</span>
     type <span class="Constant">[01]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -857,7 +857,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 
 <span class="Comment"># if newline, move cursor to start of next line, and maybe align indent with previous line</span>
 
-<span class="muData">container</span> editor-data [
+<span class="muData">container</span> editor [
   indent?:bool
 ]
 
@@ -868,13 +868,13 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="muScenario">scenario</span> editor-moves-cursor-down-after-inserting-newline [
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
   assume-console [
     type <span class="Constant">[0</span>
 <span class="Constant">1]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -897,7 +897,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Delimiter">}</span>
 ]
 
-<span class="muRecipe">def</span> insert-new-line-and-indent editor:&amp;:editor-data, screen:&amp;:screen<span class="muRecipe"> -&gt; </span>editor:&amp;:editor-data, screen:&amp;:screen, go-render?:bool [
+<span class="muRecipe">def</span> insert-new-line-and-indent editor:&amp;:editor, screen:&amp;:screen<span class="muRecipe"> -&gt; </span>editor:&amp;:editor, screen:&amp;:screen, go-render?:bool [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   cursor-row:num<span class="Special"> &lt;- </span>get *editor, <span class="Constant">cursor-row:offset</span>
@@ -974,13 +974,13 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="muScenario">scenario</span> editor-moves-cursor-down-after-inserting-newline-2 [
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">1/left</span>, <span class="Constant">10/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">1/left</span>, <span class="Constant">10/right</span>
   assume-console [
     type <span class="Constant">[0</span>
 <span class="Constant">1]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -994,7 +994,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="muScenario">scenario</span> editor-clears-previous-line-completely-after-inserting-newline [
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abcde]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
   assume-console [
     press enter
   ]
@@ -1006,7 +1006,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
    <span class="Constant"> .          .</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># line should be fully cleared</span>
   screen-should-contain [
@@ -1023,7 +1023,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[ab</span>
 <span class="Constant">  cd</span>
 <span class="Constant">ef]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
   <span class="Comment"># position cursor after 'cd' and hit 'newline'</span>
   assume-console [
     left-click <span class="Constant">2</span>, <span class="Constant">8</span>
@@ -1031,9 +1031,9 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 ]
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   <span class="Comment"># cursor should be below start of previous line</span>
   memory-should-contain [
@@ -1047,7 +1047,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[ab</span>
 <span class="Constant">  cd</span>
 <span class="Constant">ef]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
   <span class="Comment"># position cursor after 'cd' and hit 'newline' surrounded by paste markers</span>
   assume-console [
     left-click <span class="Constant">2</span>, <span class="Constant">8</span>
@@ -1056,9 +1056,9 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press <span class="Constant">65506</span>  <span class="Comment"># end paste</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   <span class="Comment"># cursor should be below start of previous line</span>
   memory-should-contain [
@@ -1110,7 +1110,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Delimiter">}</span>
   screen<span class="Special"> &lt;- </span>move-cursor screen, row, x
   <span class="Delimiter">{</span>
-    continue?:bool<span class="Special"> &lt;- </span>lesser-or-equal x, right  <span class="Comment"># right is inclusive, to match editor-data semantics</span>
+    continue?:bool<span class="Special"> &lt;- </span>lesser-or-equal x, right  <span class="Comment"># right is inclusive, to match editor semantics</span>
     <span class="muControl">break-unless</span> continue?
     print screen, style, color, bg-color
     x<span class="Special"> &lt;- </span>add x, <span class="Constant">1</span>
diff --git a/html/edit/003-shortcuts.mu.html b/html/edit/003-shortcuts.mu.html
index 90879f62..8a6f0fbc 100644
--- a/html/edit/003-shortcuts.mu.html
+++ b/html/edit/003-shortcuts.mu.html
@@ -43,12 +43,12 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Comment"># just one character in final line</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[ab</span>
 <span class="Constant">cd]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
   assume-console [
     press tab
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -75,17 +75,17 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="muScenario">scenario</span> editor-handles-backspace-key [
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
 <span class="Constant">  $clear-trace</span>
   assume-console [
     left-click <span class="Constant">1</span>, <span class="Constant">1</span>
     press backspace
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">5</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">5</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -114,7 +114,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="Comment"># return values:</span>
 <span class="Comment">#   go-render? - whether caller needs to update the screen</span>
 <span class="Comment">#   backspaced-cell - value deleted (or 0 if nothing was deleted) so we can save it for undo, etc.</span>
-<span class="muRecipe">def</span> delete-before-cursor editor:&amp;:editor-data, screen:&amp;:screen<span class="muRecipe"> -&gt; </span>editor:&amp;:editor-data, screen:&amp;:screen, go-render?:bool, backspaced-cell:&amp;:duplex-list:char [
+<span class="muRecipe">def</span> delete-before-cursor editor:&amp;:editor, screen:&amp;:screen<span class="muRecipe"> -&gt; </span>editor:&amp;:editor, screen:&amp;:screen, go-render?:bool, backspaced-cell:&amp;:duplex-list:char [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   before-cursor:&amp;:duplex-list:char<span class="Special"> &lt;- </span>get *editor, <span class="Constant">before-cursor:offset</span>
@@ -165,7 +165,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   go-render?<span class="Special"> &lt;- </span>copy <span class="Constant">0/false</span>
 ]
 
-<span class="muRecipe">def</span> move-cursor-coordinates-left editor:&amp;:editor-data<span class="muRecipe"> -&gt; </span>editor:&amp;:editor-data, go-render?:bool [
+<span class="muRecipe">def</span> move-cursor-coordinates-left editor:&amp;:editor<span class="muRecipe"> -&gt; </span>editor:&amp;:editor, go-render?:bool [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   before-cursor:&amp;:duplex-list:char<span class="Special"> &lt;- </span>get *editor, <span class="Constant">before-cursor:offset</span>
@@ -254,15 +254,15 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Comment"># just one character in final line</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[ab</span>
 <span class="Constant">cd]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
   assume-console [
     left-click <span class="Constant">2</span>, <span class="Constant">0</span>  <span class="Comment"># cursor at only character in final line</span>
     press backspace
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">5</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">5</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -281,8 +281,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Comment"># initialize editor with two long-ish but non-wrapping lines</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc def</span>
 <span class="Constant">ghi jkl]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
 <span class="Constant">  $clear-trace</span>
   <span class="Comment"># position the cursor at the start of the second and hit backspace</span>
   assume-console [
@@ -290,7 +290,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press backspace
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># resulting single line should wrap correctly</span>
   screen-should-contain [
@@ -306,8 +306,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Comment"># initialize editor in part of the screen with a long line</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc def ghij]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">8/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">8/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
   <span class="Comment"># confirm that it wraps</span>
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -322,7 +322,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press backspace
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># resulting single line should wrap correctly and not overflow its bounds</span>
   screen-should-contain [
@@ -339,14 +339,14 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="muScenario">scenario</span> editor-handles-delete-key [
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
 <span class="Constant">  $clear-trace</span>
   assume-console [
     press delete
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -360,7 +360,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press delete
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -382,7 +382,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Delimiter">}</span>
 ]
 
-<span class="muRecipe">def</span> delete-at-cursor editor:&amp;:editor-data, screen:&amp;:screen<span class="muRecipe"> -&gt; </span>editor:&amp;:editor-data, screen:&amp;:screen, go-render?:bool, deleted-cell:&amp;:duplex-list:char [
+<span class="muRecipe">def</span> delete-at-cursor editor:&amp;:editor, screen:&amp;:screen<span class="muRecipe"> -&gt; </span>editor:&amp;:editor, screen:&amp;:screen, go-render?:bool, deleted-cell:&amp;:duplex-list:char [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   before-cursor:&amp;:duplex-list:char<span class="Special"> &lt;- </span>get *editor, <span class="Constant">before-cursor:offset</span>
@@ -428,15 +428,15 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="muScenario">scenario</span> editor-moves-cursor-right-with-key [
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
 <span class="Constant">  $clear-trace</span>
   assume-console [
     press right-arrow
     type <span class="Constant">[0]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -466,7 +466,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Delimiter">}</span>
 ]
 
-<span class="muRecipe">def</span> move-cursor-coordinates-right editor:&amp;:editor-data, screen-height:num<span class="muRecipe"> -&gt; </span>editor:&amp;:editor-data, go-render?:bool [
+<span class="muRecipe">def</span> move-cursor-coordinates-right editor:&amp;:editor, screen-height:num<span class="muRecipe"> -&gt; </span>editor:&amp;:editor, go-render?:bool [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   before-cursor:&amp;:duplex-list:char<span class="Special"> &lt;- </span>get *editor <span class="Constant">before-cursor:offset</span>
@@ -526,8 +526,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc</span>
 <span class="Constant">d]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
 <span class="Constant">  $clear-trace</span>
   <span class="Comment"># type right-arrow a few times to get to start of second line</span>
   assume-console [
@@ -537,7 +537,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press right-arrow  <span class="Comment"># next line</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   check-trace-count-for-label <span class="Constant">0</span>, <span class="Constant">[print-character]</span>
   <span class="Comment"># type something and ensure it goes where it should</span>
@@ -545,7 +545,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     type <span class="Constant">[0]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -561,8 +561,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc</span>
 <span class="Constant">d]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">1/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">1/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
   assume-console [
     press right-arrow
     press right-arrow
@@ -571,7 +571,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     type <span class="Constant">[0]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -585,17 +585,17 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="muScenario">scenario</span> editor-moves-cursor-to-next-wrapped-line-with-right-arrow [
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abcdef]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
 <span class="Constant">  $clear-trace</span>
   assume-console [
     left-click <span class="Constant">1</span>, <span class="Constant">3</span>
     press right-arrow
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -615,8 +615,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Comment"># line just barely wrapping</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abcde]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
 <span class="Constant">  $clear-trace</span>
   <span class="Comment"># position cursor at last character before wrap and hit right-arrow</span>
   assume-console [
@@ -624,9 +624,9 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press right-arrow
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   memory-should-contain [
     <span class="Constant">3</span><span class="Special"> &lt;- </span><span class="Constant">2</span>
@@ -637,9 +637,9 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press right-arrow
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   memory-should-contain [
     <span class="Constant">3</span><span class="Special"> &lt;- </span><span class="Constant">2</span>
@@ -651,17 +651,17 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="muScenario">scenario</span> editor-moves-cursor-to-next-wrapped-line-with-right-arrow-3 [
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abcdef]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">1/left</span>, <span class="Constant">6/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">1/left</span>, <span class="Constant">6/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
 <span class="Constant">  $clear-trace</span>
   assume-console [
     left-click <span class="Constant">1</span>, <span class="Constant">4</span>
     press right-arrow
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -681,8 +681,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc</span>
 <span class="Constant">d]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
 <span class="Constant">  $clear-trace</span>
   <span class="Comment"># move to end of line, press right-arrow, type a character</span>
   assume-console [
@@ -691,7 +691,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     type <span class="Constant">[0]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># new character should be in next line</span>
   screen-should-contain [
@@ -711,8 +711,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="muScenario">scenario</span> editor-moves-cursor-left-with-key [
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
 <span class="Constant">  $clear-trace</span>
   assume-console [
     left-click <span class="Constant">1</span>, <span class="Constant">2</span>
@@ -720,7 +720,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     type <span class="Constant">[0]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -755,8 +755,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Comment"># initialize editor with two lines</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc</span>
 <span class="Constant">d]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
 <span class="Constant">  $clear-trace</span>
   <span class="Comment"># position cursor at start of second line (so there's no previous newline)</span>
   assume-console [
@@ -764,9 +764,9 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press left-arrow
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   memory-should-contain [
     <span class="Constant">3</span><span class="Special"> &lt;- </span><span class="Constant">1</span>
@@ -781,8 +781,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc</span>
 <span class="Constant">def</span>
 <span class="Constant">g]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
 <span class="Constant">  $clear-trace</span>
   <span class="Comment"># position cursor further down (so there's a newline before the character at</span>
   <span class="Comment"># the cursor)</span>
@@ -792,7 +792,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     type <span class="Constant">[0]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -809,8 +809,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc</span>
 <span class="Constant">def</span>
 <span class="Constant">g]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
 <span class="Constant">  $clear-trace</span>
   <span class="Comment"># position cursor at start of text, press left-arrow, then type a character</span>
   assume-console [
@@ -819,7 +819,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     type <span class="Constant">[0]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># left-arrow should have had no effect</span>
   screen-should-contain [
@@ -838,8 +838,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc</span>
 
 d]
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
 <span class="Constant">  $clear-trace</span>
   <span class="Comment"># position cursor right after empty line</span>
   assume-console [
@@ -848,7 +848,7 @@ d]
     type <span class="Constant">[0]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -864,8 +864,8 @@ d]
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Comment"># initialize editor with a wrapping line</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abcdef]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
 <span class="Constant">  $clear-trace</span>
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -880,9 +880,9 @@ d]
     press left-arrow
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   memory-should-contain [
     <span class="Constant">3</span><span class="Special"> &lt;- </span><span class="Constant">1</span>  <span class="Comment"># previous row</span>
@@ -896,8 +896,8 @@ d]
   <span class="Comment"># initialize editor with a wrapping line followed by a second line</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abcdef</span>
 <span class="Constant">g]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
 <span class="Constant">  $clear-trace</span>
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -912,9 +912,9 @@ d]
     press left-arrow
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   memory-should-contain [
     <span class="Constant">3</span><span class="Special"> &lt;- </span><span class="Constant">2</span>  <span class="Comment"># previous row</span>
@@ -928,8 +928,8 @@ d]
   <span class="Comment"># initialize editor with a line on the verge of wrapping, followed by a second line</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abcd</span>
 <span class="Constant">e]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
 <span class="Constant">  $clear-trace</span>
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -944,9 +944,9 @@ d]
     press left-arrow
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   memory-should-contain [
     <span class="Constant">3</span><span class="Special"> &lt;- </span><span class="Constant">1</span>  <span class="Comment"># previous row</span>
@@ -963,17 +963,17 @@ d]
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc</span>
 <span class="Constant">def]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
 <span class="Constant">  $clear-trace</span>
   assume-console [
     left-click <span class="Constant">2</span>, <span class="Constant">1</span>
     press up-arrow
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   memory-should-contain [
     <span class="Constant">3</span><span class="Special"> &lt;- </span><span class="Constant">1</span>
@@ -984,7 +984,7 @@ d]
     type <span class="Constant">[0]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -1007,7 +1007,7 @@ d]
   <span class="Delimiter">}</span>
 ]
 
-<span class="muRecipe">def</span> move-to-previous-line editor:&amp;:editor-data<span class="muRecipe"> -&gt; </span>editor:&amp;:editor-data, go-render?:bool [
+<span class="muRecipe">def</span> move-to-previous-line editor:&amp;:editor<span class="muRecipe"> -&gt; </span>editor:&amp;:editor, go-render?:bool [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   cursor-row:num<span class="Special"> &lt;- </span>get *editor, <span class="Constant">cursor-row:offset</span>
@@ -1079,17 +1079,17 @@ d]
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[ab</span>
 <span class="Constant">def]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
 <span class="Constant">  $clear-trace</span>
   assume-console [
     left-click <span class="Constant">2</span>, <span class="Constant">3</span>
     press up-arrow
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   memory-should-contain [
     <span class="Constant">3</span><span class="Special"> &lt;- </span><span class="Constant">1</span>
@@ -1100,7 +1100,7 @@ d]
     type <span class="Constant">[0]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -1115,17 +1115,17 @@ d]
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new [
 <span class="muRecipe">def</span>]
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
 <span class="Constant">  $clear-trace</span>
   assume-console [
     left-click <span class="Constant">2</span>, <span class="Constant">3</span>
     press up-arrow
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   memory-should-contain [
     <span class="Constant">3</span><span class="Special"> &lt;- </span><span class="Constant">1</span>
@@ -1136,7 +1136,7 @@ d]
     type <span class="Constant">[0]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -1153,8 +1153,8 @@ d]
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc</span>
 <span class="Constant">def</span>
 <span class="Constant">ghi]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
 <span class="Constant">  $clear-trace</span>
   <span class="Comment"># click on the third line and hit up-arrow, so you end up just after a newline</span>
   assume-console [
@@ -1162,9 +1162,9 @@ d]
     press up-arrow
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   memory-should-contain [
     <span class="Constant">3</span><span class="Special"> &lt;- </span><span class="Constant">2</span>
@@ -1175,7 +1175,7 @@ d]
     type <span class="Constant">[0]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -1192,17 +1192,17 @@ d]
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc</span>
 <span class="Constant">def]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
 <span class="Constant">  $clear-trace</span>
   <span class="Comment"># cursor starts out at (1, 0)</span>
   assume-console [
     press down-arrow
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   <span class="Comment"># ..and ends at (2, 0)</span>
   memory-should-contain [
@@ -1214,7 +1214,7 @@ d]
     type <span class="Constant">[0]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -1237,7 +1237,7 @@ d]
   <span class="Delimiter">}</span>
 ]
 
-<span class="muRecipe">def</span> move-to-next-line editor:&amp;:editor-data, screen-height:num<span class="muRecipe"> -&gt; </span>editor:&amp;:editor-data, go-render?:bool [
+<span class="muRecipe">def</span> move-to-next-line editor:&amp;:editor, screen-height:num<span class="muRecipe"> -&gt; </span>editor:&amp;:editor, go-render?:bool [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   cursor-row:num<span class="Special"> &lt;- </span>get *editor, <span class="Constant">cursor-row:offset</span>
@@ -1297,17 +1297,17 @@ d]
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc</span>
 <span class="Constant">de]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
 <span class="Constant">  $clear-trace</span>
   assume-console [
     left-click <span class="Constant">1</span>, <span class="Constant">3</span>
     press down-arrow
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   memory-should-contain [
     <span class="Constant">3</span><span class="Special"> &lt;- </span><span class="Constant">2</span>
@@ -1318,7 +1318,7 @@ d]
     type <span class="Constant">[0]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -1335,8 +1335,8 @@ d]
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[123</span>
 <span class="Constant">456]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
 <span class="Constant">  $clear-trace</span>
   <span class="Comment"># start on second line, press ctrl-a</span>
   assume-console [
@@ -1344,9 +1344,9 @@ d]
     press ctrl-a
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">5</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">5</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   <span class="Comment"># cursor moves to start of line</span>
   memory-should-contain [
@@ -1382,7 +1382,7 @@ d]
   <span class="Delimiter">}</span>
 ]
 
-<span class="muRecipe">def</span> move-to-start-of-line editor:&amp;:editor-data<span class="muRecipe"> -&gt; </span>editor:&amp;:editor-data [
+<span class="muRecipe">def</span> move-to-start-of-line editor:&amp;:editor<span class="muRecipe"> -&gt; </span>editor:&amp;:editor [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   <span class="Comment"># update cursor column</span>
@@ -1410,8 +1410,8 @@ d]
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[123</span>
 <span class="Constant">456]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
 <span class="Constant">  $clear-trace</span>
   <span class="Comment"># start on first line (no newline before), press ctrl-a</span>
   assume-console [
@@ -1419,9 +1419,9 @@ d]
     press ctrl-a
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">5</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">5</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   <span class="Comment"># cursor moves to start of line</span>
   memory-should-contain [
@@ -1435,7 +1435,7 @@ d]
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[123</span>
 <span class="Constant">456]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
 <span class="Constant">  $clear-trace</span>
   <span class="Comment"># start on second line, press 'home'</span>
   assume-console [
@@ -1443,9 +1443,9 @@ d]
     press home
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   <span class="Comment"># cursor moves to start of line</span>
   memory-should-contain [
@@ -1459,8 +1459,8 @@ d]
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[123</span>
 <span class="Constant">456]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
 <span class="Constant">  $clear-trace</span>
   <span class="Comment"># start on first line (no newline before), press 'home'</span>
   assume-console [
@@ -1468,9 +1468,9 @@ d]
     press home
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   <span class="Comment"># cursor moves to start of line</span>
   memory-should-contain [
@@ -1486,8 +1486,8 @@ d]
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[123</span>
 <span class="Constant">456]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
 <span class="Constant">  $clear-trace</span>
   <span class="Comment"># start on first line, press ctrl-e</span>
   assume-console [
@@ -1495,9 +1495,9 @@ d]
     press ctrl-e
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">5</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">5</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   <span class="Comment"># cursor moves to end of line</span>
   memory-should-contain [
@@ -1510,9 +1510,9 @@ d]
     type <span class="Constant">[z]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">5</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">5</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   memory-should-contain [
     <span class="Constant">4</span><span class="Special"> &lt;- </span><span class="Constant">1</span>
@@ -1554,7 +1554,7 @@ d]
   <span class="Delimiter">}</span>
 ]
 
-<span class="muRecipe">def</span> move-to-end-of-line editor:&amp;:editor-data<span class="muRecipe"> -&gt; </span>editor:&amp;:editor-data [
+<span class="muRecipe">def</span> move-to-end-of-line editor:&amp;:editor<span class="muRecipe"> -&gt; </span>editor:&amp;:editor [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   before-cursor:&amp;:duplex-list:char<span class="Special"> &lt;- </span>get *editor, <span class="Constant">before-cursor:offset</span>
@@ -1578,8 +1578,8 @@ d]
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[123</span>
 <span class="Constant">456]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
 <span class="Constant">  $clear-trace</span>
   <span class="Comment"># start on second line (no newline after), press ctrl-e</span>
   assume-console [
@@ -1587,9 +1587,9 @@ d]
     press ctrl-e
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">5</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">5</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   <span class="Comment"># cursor moves to end of line</span>
   memory-should-contain [
@@ -1603,8 +1603,8 @@ d]
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[123</span>
 <span class="Constant">456]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
 <span class="Constant">  $clear-trace</span>
   <span class="Comment"># start on first line, press 'end'</span>
   assume-console [
@@ -1612,9 +1612,9 @@ d]
     press end
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   <span class="Comment"># cursor moves to end of line</span>
   memory-should-contain [
@@ -1628,8 +1628,8 @@ d]
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[123</span>
 <span class="Constant">456]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
 <span class="Constant">  $clear-trace</span>
   <span class="Comment"># start on second line (no newline after), press 'end'</span>
   assume-console [
@@ -1637,9 +1637,9 @@ d]
     press end
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   <span class="Comment"># cursor moves to end of line</span>
   memory-should-contain [
@@ -1655,14 +1655,14 @@ d]
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[123</span>
 <span class="Constant">456]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
   <span class="Comment"># start on second line, press ctrl-u</span>
   assume-console [
     left-click <span class="Constant">2</span>, <span class="Constant">2</span>
     press ctrl-u
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># cursor deletes to start of line</span>
   screen-should-contain [
@@ -1686,7 +1686,7 @@ d]
   <span class="Delimiter">}</span>
 ]
 
-<span class="muRecipe">def</span> delete-to-start-of-line editor:&amp;:editor-data<span class="muRecipe"> -&gt; </span>result:&amp;:duplex-list:char, editor:&amp;:editor-data [
+<span class="muRecipe">def</span> delete-to-start-of-line editor:&amp;:editor<span class="muRecipe"> -&gt; </span>result:&amp;:duplex-list:char, editor:&amp;:editor [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   <span class="Comment"># compute range to delete</span>
@@ -1718,14 +1718,14 @@ d]
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[123</span>
 <span class="Constant">456]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
   <span class="Comment"># start on first line (no newline before), press ctrl-u</span>
   assume-console [
     left-click <span class="Constant">1</span>, <span class="Constant">2</span>
     press ctrl-u
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># cursor deletes to start of line</span>
   screen-should-contain [
@@ -1741,14 +1741,14 @@ d]
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[123</span>
 <span class="Constant">456]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
   <span class="Comment"># start past end of line, press ctrl-u</span>
   assume-console [
     left-click <span class="Constant">1</span>, <span class="Constant">3</span>
     press ctrl-u
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># cursor deletes to start of line</span>
   screen-should-contain [
@@ -1764,14 +1764,14 @@ d]
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[123</span>
 <span class="Constant">456]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
   <span class="Comment"># start past end of final line, press ctrl-u</span>
   assume-console [
     left-click <span class="Constant">2</span>, <span class="Constant">3</span>
     press ctrl-u
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># cursor deletes to start of line</span>
   screen-should-contain [
@@ -1789,14 +1789,14 @@ d]
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[123</span>
 <span class="Constant">456]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
   <span class="Comment"># start on first line, press ctrl-k</span>
   assume-console [
     left-click <span class="Constant">1</span>, <span class="Constant">1</span>
     press ctrl-k
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># cursor deletes to end of line</span>
   screen-should-contain [
@@ -1820,7 +1820,7 @@ d]
   <span class="Delimiter">}</span>
 ]
 
-<span class="muRecipe">def</span> delete-to-end-of-line editor:&amp;:editor-data<span class="muRecipe"> -&gt; </span>result:&amp;:duplex-list:char, editor:&amp;:editor-data [
+<span class="muRecipe">def</span> delete-to-end-of-line editor:&amp;:editor<span class="muRecipe"> -&gt; </span>result:&amp;:duplex-list:char, editor:&amp;:editor [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   <span class="Comment"># compute range to delete</span>
@@ -1844,14 +1844,14 @@ d]
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[123</span>
 <span class="Constant">456]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
   <span class="Comment"># start on second line (no newline after), press ctrl-k</span>
   assume-console [
     left-click <span class="Constant">2</span>, <span class="Constant">1</span>
     press ctrl-k
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># cursor deletes to end of line</span>
   screen-should-contain [
@@ -1867,14 +1867,14 @@ d]
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[123</span>
 <span class="Constant">456]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
   <span class="Comment"># start at end of line</span>
   assume-console [
     left-click <span class="Constant">1</span>, <span class="Constant">2</span>
     press ctrl-k
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># cursor deletes just last character</span>
   screen-should-contain [
@@ -1890,14 +1890,14 @@ d]
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[123</span>
 <span class="Constant">456]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
   <span class="Comment"># start past end of line</span>
   assume-console [
     left-click <span class="Constant">1</span>, <span class="Constant">3</span>
     press ctrl-k
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># cursor deletes nothing</span>
   screen-should-contain [
@@ -1913,14 +1913,14 @@ d]
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[123</span>
 <span class="Constant">456]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
   <span class="Comment"># start at end of text</span>
   assume-console [
     left-click <span class="Constant">2</span>, <span class="Constant">2</span>
     press ctrl-k
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># cursor deletes just the final character</span>
   screen-should-contain [
@@ -1936,14 +1936,14 @@ d]
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[123</span>
 <span class="Constant">456]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
   <span class="Comment"># start past end of text</span>
   assume-console [
     left-click <span class="Constant">2</span>, <span class="Constant">3</span>
     press ctrl-k
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># cursor deletes nothing</span>
   screen-should-contain [
@@ -1965,7 +1965,7 @@ d]
 <span class="Constant">b</span>
 <span class="Constant">c</span>
 <span class="Constant">d]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
   screen-should-contain [
    <span class="Constant"> .          .</span>
    <span class="Constant"> .a         .</span>
@@ -1978,7 +1978,7 @@ d]
     press down-arrow
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># screen slides by one line</span>
   screen-should-contain [
@@ -2043,7 +2043,7 @@ d]
 <span class="Constant">g</span>
 <span class="Constant">h</span>
 <span class="Constant">i]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
   screen-should-contain [
    <span class="Constant"> .          .</span>
    <span class="Constant"> .abcd↩     .</span>
@@ -2056,7 +2056,7 @@ d]
     press down-arrow
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># screen shows partial wrapped line</span>
   screen-should-contain [
@@ -2075,14 +2075,14 @@ d]
 <span class="Constant">k</span>
 <span class="Constant">l</span>
 <span class="Constant">m]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
   <span class="Comment"># position cursor at last line, then try to move further down</span>
   assume-console [
     left-click <span class="Constant">3</span>, <span class="Constant">0</span>
     press down-arrow
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># screen shows partial wrapped line containing a wrap icon</span>
   screen-should-contain [
@@ -2096,7 +2096,7 @@ d]
     press down-arrow
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># screen shows partial wrapped line</span>
   screen-should-contain [
@@ -2114,16 +2114,16 @@ d]
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[a</span>
 <span class="Constant">b</span>
 <span class="Constant">cdef]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
   <span class="Comment"># position cursor at end, type a character</span>
   assume-console [
     left-click <span class="Constant">3</span>, <span class="Constant">4</span>
     type <span class="Constant">[g]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   <span class="Comment"># screen scrolls</span>
   screen-should-contain [
@@ -2144,16 +2144,16 @@ d]
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[a</span>
 <span class="Constant">b</span>
 <span class="Constant">c]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
   assume-console [
     left-click <span class="Constant">3</span>, <span class="Constant">4</span>
     type [
 ]
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   <span class="Comment"># screen scrolls</span>
   screen-should-contain [
@@ -2175,16 +2175,16 @@ d]
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[a</span>
 <span class="Constant">b</span>
 <span class="Constant">cdefgh]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
   <span class="Comment"># position cursor at end of screen and try to move right</span>
   assume-console [
     left-click <span class="Constant">3</span>, <span class="Constant">3</span>
     press right-arrow
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   <span class="Comment"># screen scrolls</span>
   screen-should-contain [
@@ -2207,16 +2207,16 @@ d]
 <span class="Constant">b</span>
 <span class="Constant">c</span>
 <span class="Constant">d]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
   <span class="Comment"># position cursor at end of screen and try to move right</span>
   assume-console [
     left-click <span class="Constant">3</span>, <span class="Constant">3</span>
     press right-arrow
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   <span class="Comment"># screen scrolls</span>
   screen-should-contain [
@@ -2235,8 +2235,8 @@ d]
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc</span>
 <span class="Constant">de]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
 <span class="Constant">  $clear-trace</span>
   <span class="Comment"># try to move down past end of text</span>
   assume-console [
@@ -2244,9 +2244,9 @@ d]
     press down-arrow
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   <span class="Comment"># screen should scroll, moving cursor to end of text</span>
   memory-should-contain [
@@ -2257,7 +2257,7 @@ d]
     type <span class="Constant">[0]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -2272,9 +2272,9 @@ d]
     press down-arrow
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   <span class="Comment"># screen stops scrolling because cursor is already at top</span>
   memory-should-contain [
@@ -2286,7 +2286,7 @@ d]
     type <span class="Constant">[1]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -2307,7 +2307,7 @@ d]
 <span class="Constant">e</span>
 <span class="Constant">f</span>
 <span class="Constant">g]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
   <span class="Comment"># scroll down one page and one line</span>
   assume-console [
     press page-down
@@ -2315,7 +2315,7 @@ d]
     press down-arrow
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># screen scrolls down 3 lines</span>
   screen-should-contain [
@@ -2336,7 +2336,7 @@ d]
 <span class="Constant">b</span>
 <span class="Constant">c</span>
 <span class="Constant">d]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
   screen-should-contain [
    <span class="Constant"> .          .</span>
    <span class="Constant"> .a         .</span>
@@ -2349,7 +2349,7 @@ d]
     press up-arrow
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># screen slides by one line</span>
   screen-should-contain [
@@ -2374,7 +2374,7 @@ d]
 <span class="Comment"># takes a pointer into the doubly-linked list, scans back to before start of</span>
 <span class="Comment"># previous *wrapped* line</span>
 <span class="Comment"># beware: never return null pointer</span>
-<span class="muRecipe">def</span> before-previous-line in:&amp;:duplex-list:char, editor:&amp;:editor-data<span class="muRecipe"> -&gt; </span>out:&amp;:duplex-list:char [
+<span class="muRecipe">def</span> before-previous-line in:&amp;:duplex-list:char, editor:&amp;:editor<span class="muRecipe"> -&gt; </span>out:&amp;:duplex-list:char [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   curr:&amp;:duplex-list:char<span class="Special"> &lt;- </span>copy in
@@ -2424,7 +2424,7 @@ d]
 <span class="Constant">g</span>
 <span class="Constant">h</span>
 <span class="Constant">i]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
   screen-should-contain [
    <span class="Constant"> .          .</span>
    <span class="Constant"> .abcd↩     .</span>
@@ -2436,7 +2436,7 @@ d]
     press page-down
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -2449,7 +2449,7 @@ d]
     press up-arrow
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># screen shows partial wrapped line</span>
   screen-should-contain [
@@ -2468,13 +2468,13 @@ d]
 <span class="Constant">k</span>
 <span class="Constant">l</span>
 <span class="Constant">m]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
   <span class="Comment"># position cursor at top of second page</span>
   assume-console [
     press page-down
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -2488,7 +2488,7 @@ d]
     press up-arrow
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># screen shows partial wrapped line</span>
   screen-should-contain [
@@ -2503,7 +2503,7 @@ d]
     press up-arrow
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># screen shows partial wrapped line</span>
   screen-should-contain [
@@ -2518,7 +2518,7 @@ d]
     press up-arrow
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># screen shows partial wrapped line</span>
   screen-should-contain [
@@ -2541,7 +2541,7 @@ d]
 <span class="Constant">g</span>
 <span class="Constant">h</span>
 <span class="Constant">i]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">6/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">6/right</span>
   screen-should-contain [
    <span class="Constant"> .          .</span>
    <span class="Constant"> .abcde↩    .</span>
@@ -2553,7 +2553,7 @@ d]
     press page-down
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -2566,7 +2566,7 @@ d]
     press up-arrow
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># screen shows partial wrapped line</span>
   screen-should-contain [
@@ -2587,12 +2587,12 @@ d]
 c
 d
 e]
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">6/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">6/right</span>
   assume-console [
     press page-down
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -2604,7 +2604,7 @@ e]
     press page-down
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -2616,7 +2616,7 @@ e]
     press page-up
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -2635,13 +2635,13 @@ e]
 <span class="Constant">c</span>
 <span class="Constant">d</span>
 <span class="Constant">e]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
   <span class="Comment"># position cursor at top of second page</span>
   assume-console [
     press page-down
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .     .</span>
@@ -2654,9 +2654,9 @@ e]
     press left-arrow
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   <span class="Comment"># screen scrolls</span>
   screen-should-contain [
@@ -2679,7 +2679,7 @@ e]
 <span class="Constant">b</span>
 <span class="Constant">c</span>
 <span class="Constant">d]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
   screen-should-contain [
    <span class="Constant"> .          .</span>
    <span class="Constant"> .a         .</span>
@@ -2694,7 +2694,7 @@ e]
     press up-arrow
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># screen slides by one line</span>
   screen-should-contain [
@@ -2708,7 +2708,7 @@ e]
     press up-arrow
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># screen remains unchanged</span>
   screen-should-contain [
@@ -2727,7 +2727,7 @@ e]
 <span class="Constant">b</span>
 <span class="Constant">c</span>
 <span class="Constant">d]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
   screen-should-contain [
    <span class="Constant"> .          .</span>
    <span class="Constant"> .a         .</span>
@@ -2739,7 +2739,7 @@ e]
     press page-down
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># screen shows next page</span>
   screen-should-contain [
@@ -2784,7 +2784,7 @@ e]
 
 <span class="Comment"># page-down skips entire wrapped lines, so it can't scroll past lines</span>
 <span class="Comment"># taking up the entire screen</span>
-<span class="muRecipe">def</span> page-down editor:&amp;:editor-data<span class="muRecipe"> -&gt; </span>editor:&amp;:editor-data [
+<span class="muRecipe">def</span> page-down editor:&amp;:editor<span class="muRecipe"> -&gt; </span>editor:&amp;:editor [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   <span class="Comment"># if editor contents don't overflow screen, do nothing</span>
@@ -2812,8 +2812,8 @@ e]
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">4/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[a</span>
 <span class="Constant">b]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
   screen-should-contain [
    <span class="Constant"> .          .</span>
    <span class="Constant"> .a         .</span>
@@ -2825,7 +2825,7 @@ e]
     press page-down
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># screen remains unmodified</span>
   screen-should-contain [
@@ -2844,7 +2844,7 @@ e]
 <span class="Constant">b</span>
 <span class="Constant">cdefgh]</span>
   <span class="Comment"># editor screen triggers wrap of last line</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">4/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">4/right</span>
   <span class="Comment"># some part of last line is not displayed</span>
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -2857,7 +2857,7 @@ e]
     press page-down
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># screen shows entire wrapped line</span>
   screen-should-contain [
@@ -2875,7 +2875,7 @@ e]
   <span class="Comment"># and still has something left over</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[a</span>
 <span class="Constant">bcdefgh]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">4/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">4/right</span>
   <span class="Comment"># some part of last line is not displayed</span>
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -2888,7 +2888,7 @@ e]
     press page-down
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># screen shows entire wrapped line</span>
   screen-should-contain [
@@ -2907,7 +2907,7 @@ e]
 <span class="Constant">b</span>
 <span class="Constant">c</span>
 <span class="Constant">d]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
   screen-should-contain [
    <span class="Constant"> .          .</span>
    <span class="Constant"> .a         .</span>
@@ -2919,7 +2919,7 @@ e]
     press page-down
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># screen shows next page</span>
   screen-should-contain [
@@ -2933,7 +2933,7 @@ e]
     press page-up
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># screen shows original page again</span>
   screen-should-contain [
@@ -2977,7 +2977,7 @@ e]
   <span class="Delimiter">}</span>
 ]
 
-<span class="muRecipe">def</span> page-up editor:&amp;:editor-data, screen-height:num<span class="muRecipe"> -&gt; </span>editor:&amp;:editor-data [
+<span class="muRecipe">def</span> page-up editor:&amp;:editor, screen-height:num<span class="muRecipe"> -&gt; </span>editor:&amp;:editor [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   max:num<span class="Special"> &lt;- </span>subtract screen-height, <span class="Constant">1/menu-bar</span>, <span class="Constant">1/overlapping-line</span>
@@ -3007,7 +3007,7 @@ e]
 <span class="Constant">f</span>
 <span class="Constant">g</span>
 <span class="Constant">h]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
   screen-should-contain [
    <span class="Constant"> .          .</span>
    <span class="Constant"> .a         .</span>
@@ -3020,7 +3020,7 @@ e]
     press page-down
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># screen shows third page</span>
   screen-should-contain [
@@ -3034,7 +3034,7 @@ e]
     press page-up
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># screen shows second page</span>
   screen-should-contain [
@@ -3048,7 +3048,7 @@ e]
     press page-up
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># screen shows original page again</span>
   screen-should-contain [
@@ -3074,7 +3074,7 @@ e]
 <span class="Constant">n</span>
 <span class="Constant">o]</span>
   <span class="Comment"># editor screen triggers wrap of last line</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">4/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">4/right</span>
   <span class="Comment"># some part of last line is not displayed</span>
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -3091,7 +3091,7 @@ e]
     press down-arrow
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># screen shows entire wrapped line</span>
   screen-should-contain [
@@ -3107,7 +3107,7 @@ e]
     press page-up
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># screen resets</span>
   screen-should-contain [
@@ -3127,7 +3127,7 @@ e]
   <span class="Comment"># and still has something left over</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[a</span>
 <span class="Constant">bcdefgh]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">4/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">4/right</span>
   <span class="Comment"># some part of last line is not displayed</span>
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -3140,7 +3140,7 @@ e]
     press page-down
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># screen shows entire wrapped line</span>
   screen-should-contain [
@@ -3154,7 +3154,7 @@ e]
     press page-up
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># screen resets</span>
   screen-should-contain [
@@ -3177,7 +3177,7 @@ e]
 <span class="Constant">gxx</span>
 <span class="Constant">hxx</span>
 <span class="Constant">]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">4/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">4/right</span>
   screen-should-contain [
    <span class="Constant"> .          .</span>
    <span class="Constant"> .axx       .</span>
@@ -3188,7 +3188,7 @@ e]
     press page-down
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -3200,7 +3200,7 @@ e]
     press page-down
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -3213,7 +3213,7 @@ e]
     press page-up
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -3235,7 +3235,7 @@ exy
 fxy
 gxy
 ]
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">4/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">4/right</span>
   screen-should-contain [
    <span class="Constant"> .          .</span>
    <span class="Constant"> .axy       .</span>
@@ -3246,7 +3246,7 @@ gxy
     press page-down
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -3258,7 +3258,7 @@ gxy
     press page-down
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -3271,7 +3271,7 @@ gxy
     press page-up
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
diff --git a/html/edit/004-programming-environment.mu.html b/html/edit/004-programming-environment.mu.html
index a50eacb9..39b29125 100644
--- a/html/edit/004-programming-environment.mu.html
+++ b/html/edit/004-programming-environment.mu.html
@@ -45,25 +45,25 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   initial-recipe:text<span class="Special"> &lt;- </span>restore <span class="Constant">[recipes.mu]</span>
   initial-sandbox:text<span class="Special"> &lt;- </span>new <span class="Constant">[]</span>
   hide-screen <span class="Constant">0/screen</span>
-  env:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment <span class="Constant">0/screen</span>, initial-recipe, initial-sandbox
+  env:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment <span class="Constant">0/screen</span>, initial-recipe, initial-sandbox
   render-all <span class="Constant">0/screen</span>, env, render
   event-loop <span class="Constant">0/screen</span>, <span class="Constant">0/console</span>, env
   <span class="Comment"># never gets here</span>
 ]
 
-<span class="muData">container</span> programming-environment-data [
-  recipes:&amp;:editor-data
-  current-sandbox:&amp;:editor-data
+<span class="muData">container</span> environment [
+  recipes:&amp;:editor
+  current-sandbox:&amp;:editor
   sandbox-in-focus?:bool  <span class="Comment"># false =&gt; cursor in recipes; true =&gt; cursor in current-sandbox</span>
 ]
 
-<span class="muRecipe">def</span> new-programming-environment screen:&amp;:screen, initial-recipe-contents:text, initial-sandbox-contents:text<span class="muRecipe"> -&gt; </span>result:&amp;:programming-environment-data, screen:&amp;:screen [
+<span class="muRecipe">def</span> new-programming-environment screen:&amp;:screen, initial-recipe-contents:text, initial-sandbox-contents:text<span class="muRecipe"> -&gt; </span>result:&amp;:environment, screen:&amp;:screen [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   width:num<span class="Special"> &lt;- </span>screen-width screen
   height:num<span class="Special"> &lt;- </span>screen-height screen
   <span class="Comment"># top menu</span>
-  result<span class="Special"> &lt;- </span>new <span class="Constant">programming-environment-data:type</span>
+  result<span class="Special"> &lt;- </span>new <span class="Constant">environment:type</span>
   draw-horizontal screen, <span class="Constant">0</span>, <span class="Constant">0/left</span>, width, <span class="Constant">32/space</span>, <span class="Constant">0/black</span>, <span class="Constant">238/grey</span>
   button-start:num<span class="Special"> &lt;- </span>subtract width, <span class="Constant">20</span>
   button-on-screen?:bool<span class="Special"> &lt;- </span>greater-or-equal button-start, <span class="Constant">0</span>
@@ -74,21 +74,21 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   divider:num, _<span class="Special"> &lt;- </span>divide-with-remainder width, <span class="Constant">2</span>
   draw-vertical screen, divider, <span class="Constant">1/top</span>, height, <span class="Constant">9482/vertical-dotted</span>
   <span class="Comment"># recipe editor on the left</span>
-  recipes:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor initial-recipe-contents, screen, <span class="Constant">0/left</span>, divider/right
+  recipes:&amp;:editor<span class="Special"> &lt;- </span>new-editor initial-recipe-contents, screen, <span class="Constant">0/left</span>, divider/right
   <span class="Comment"># sandbox editor on the right</span>
   sandbox-left:num<span class="Special"> &lt;- </span>add divider, <span class="Constant">1</span>
-  current-sandbox:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor initial-sandbox-contents, screen, sandbox-left, width/right
+  current-sandbox:&amp;:editor<span class="Special"> &lt;- </span>new-editor initial-sandbox-contents, screen, sandbox-left, width/right
   *result<span class="Special"> &lt;- </span>put *result, <span class="Constant">recipes:offset</span>, recipes
   *result<span class="Special"> &lt;- </span>put *result, <span class="Constant">current-sandbox:offset</span>, current-sandbox
   *result<span class="Special"> &lt;- </span>put *result, <span class="Constant">sandbox-in-focus?:offset</span>, <span class="Constant">0/false</span>
 <span class="Constant">  &lt;programming-environment-initialization&gt;</span>
 ]
 
-<span class="muRecipe">def</span> event-loop screen:&amp;:screen, console:&amp;:console, env:&amp;:programming-environment-data<span class="muRecipe"> -&gt; </span>screen:&amp;:screen, console:&amp;:console, env:&amp;:programming-environment-data [
+<span class="muRecipe">def</span> event-loop screen:&amp;:screen, console:&amp;:console, env:&amp;:environment<span class="muRecipe"> -&gt; </span>screen:&amp;:screen, console:&amp;:console, env:&amp;:environment [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
-  recipes:&amp;:editor-data<span class="Special"> &lt;- </span>get *env, <span class="Constant">recipes:offset</span>
-  current-sandbox:&amp;:editor-data<span class="Special"> &lt;- </span>get *env, <span class="Constant">current-sandbox:offset</span>
+  recipes:&amp;:editor<span class="Special"> &lt;- </span>get *env, <span class="Constant">recipes:offset</span>
+  current-sandbox:&amp;:editor<span class="Special"> &lt;- </span>get *env, <span class="Constant">current-sandbox:offset</span>
   sandbox-in-focus?:bool<span class="Special"> &lt;- </span>get *env, <span class="Constant">sandbox-in-focus?:offset</span>
   <span class="Comment"># if we fall behind we'll stop updating the screen, but then we have to</span>
   <span class="Comment"># render the entire screen when we catch up.</span>
@@ -220,21 +220,21 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Delimiter">}</span>
 ]
 
-<span class="muRecipe">def</span> resize screen:&amp;:screen, env:&amp;:programming-environment-data<span class="muRecipe"> -&gt; </span>env:&amp;:programming-environment-data, screen:&amp;:screen [
+<span class="muRecipe">def</span> resize screen:&amp;:screen, env:&amp;:environment<span class="muRecipe"> -&gt; </span>env:&amp;:environment, screen:&amp;:screen [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   clear-screen screen  <span class="Comment"># update screen dimensions</span>
   width:num<span class="Special"> &lt;- </span>screen-width screen
   divider:num, _<span class="Special"> &lt;- </span>divide-with-remainder width, <span class="Constant">2</span>
   <span class="Comment"># update recipe editor</span>
-  recipes:&amp;:editor-data<span class="Special"> &lt;- </span>get *env, <span class="Constant">recipes:offset</span>
+  recipes:&amp;:editor<span class="Special"> &lt;- </span>get *env, <span class="Constant">recipes:offset</span>
   right:num<span class="Special"> &lt;- </span>subtract divider, <span class="Constant">1</span>
   *recipes<span class="Special"> &lt;- </span>put *recipes, <span class="Constant">right:offset</span>, right
   <span class="Comment"># reset cursor (later we'll try to preserve its position)</span>
   *recipes<span class="Special"> &lt;- </span>put *recipes, <span class="Constant">cursor-row:offset</span>, <span class="Constant">1</span>
   *recipes<span class="Special"> &lt;- </span>put *recipes, <span class="Constant">cursor-column:offset</span>, <span class="Constant">0</span>
   <span class="Comment"># update sandbox editor</span>
-  current-sandbox:&amp;:editor-data<span class="Special"> &lt;- </span>get *env, <span class="Constant">current-sandbox:offset</span>
+  current-sandbox:&amp;:editor<span class="Special"> &lt;- </span>get *env, <span class="Constant">current-sandbox:offset</span>
   left:num<span class="Special"> &lt;- </span>add divider, <span class="Constant">1</span>
   *current-sandbox<span class="Special"> &lt;- </span>put *current-sandbox, <span class="Constant">left:offset</span>, left
   right:num<span class="Special"> &lt;- </span>subtract width, <span class="Constant">1</span>
@@ -247,7 +247,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="Comment"># Variant of 'render' that updates cursor-row and cursor-column based on</span>
 <span class="Comment"># before-cursor (rather than the other way around). If before-cursor moves</span>
 <span class="Comment"># off-screen, it resets cursor-row and cursor-column.</span>
-<span class="muRecipe">def</span> render-without-moving-cursor screen:&amp;:screen, editor:&amp;:editor-data<span class="muRecipe"> -&gt; </span>last-row:num, last-column:num, screen:&amp;:screen, editor:&amp;:editor-data [
+<span class="muRecipe">def</span> render-without-moving-cursor screen:&amp;:screen, editor:&amp;:editor<span class="muRecipe"> -&gt; </span>last-row:num, last-column:num, screen:&amp;:screen, editor:&amp;:editor [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   <span class="muControl">return-unless</span> editor, <span class="Constant">1/top</span>, <span class="Constant">0/left</span>, screen/same-as-ingredient:<span class="Constant">0</span>, editor/same-as-ingredient:<span class="Constant">1</span>
@@ -276,7 +276,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     off-screen?:bool<span class="Special"> &lt;- </span>greater-or-equal row, screen-height
     <span class="muControl">break-if</span> off-screen?
     <span class="Comment"># if we find old-before-cursor still on the new resized screen, update</span>
-    <span class="Comment"># editor-data.cursor-row and editor-data.cursor-column based on</span>
+    <span class="Comment"># editor.cursor-row and editor.cursor-column based on</span>
     <span class="Comment"># old-before-cursor</span>
     <span class="Delimiter">{</span>
       at-cursor?:bool<span class="Special"> &lt;- </span>equal old-before-cursor, prev
@@ -334,7 +334,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Comment"># initialize both halves of screen</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc]</span>
   <span class="Constant">2</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[def]</span>
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
   <span class="Comment"># focus on both sides</span>
   assume-console [
     left-click <span class="Constant">1</span>, <span class="Constant">1</span>
@@ -342,11 +342,11 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   ]
   <span class="Comment"># check cursor column in each</span>
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
-    <span class="Constant">4</span>:&amp;:editor-data<span class="Special"> &lt;- </span>get *<span class="Constant">3</span>:&amp;:programming-environment-data, <span class="Constant">recipes:offset</span>
-    <span class="Constant">5</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">4</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
-    <span class="Constant">6</span>:&amp;:editor-data<span class="Special"> &lt;- </span>get *<span class="Constant">3</span>:&amp;:programming-environment-data, <span class="Constant">current-sandbox:offset</span>
-    <span class="Constant">7</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">6</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
+    <span class="Constant">4</span>:&amp;:editor<span class="Special"> &lt;- </span>get *<span class="Constant">3</span>:&amp;:environment, <span class="Constant">recipes:offset</span>
+    <span class="Constant">5</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">4</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
+    <span class="Constant">6</span>:&amp;:editor<span class="Special"> &lt;- </span>get *<span class="Constant">3</span>:&amp;:environment, <span class="Constant">current-sandbox:offset</span>
+    <span class="Constant">7</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">6</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   memory-should-contain [
     <span class="Constant">5</span><span class="Special"> &lt;- </span><span class="Constant">1</span>
@@ -360,8 +360,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Comment"># initialize both halves of screen</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc]</span>
   <span class="Constant">2</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[def]</span>
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
-  render-all screen, <span class="Constant">3</span>:&amp;:programming-environment-data, render
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  render-all screen, <span class="Constant">3</span>:&amp;:environment, render
   <span class="Comment"># type one letter in each of them</span>
   assume-console [
     left-click <span class="Constant">1</span>, <span class="Constant">1</span>
@@ -370,11 +370,11 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     type <span class="Constant">[1]</span>
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
-    <span class="Constant">4</span>:&amp;:editor-data<span class="Special"> &lt;- </span>get *<span class="Constant">3</span>:&amp;:programming-environment-data, <span class="Constant">recipes:offset</span>
-    <span class="Constant">5</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">4</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
-    <span class="Constant">6</span>:&amp;:editor-data<span class="Special"> &lt;- </span>get *<span class="Constant">3</span>:&amp;:programming-environment-data, <span class="Constant">current-sandbox:offset</span>
-    <span class="Constant">7</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">6</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
+    <span class="Constant">4</span>:&amp;:editor<span class="Special"> &lt;- </span>get *<span class="Constant">3</span>:&amp;:environment, <span class="Constant">recipes:offset</span>
+    <span class="Constant">5</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">4</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
+    <span class="Constant">6</span>:&amp;:editor<span class="Special"> &lt;- </span>get *<span class="Constant">3</span>:&amp;:environment, <span class="Constant">current-sandbox:offset</span>
+    <span class="Constant">7</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">6</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   screen-should-contain [
    <span class="Constant"> .           run (F4)           .  # this line has a different background, but we don't test that yet</span>
@@ -405,8 +405,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   run [
     <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc]</span>
     <span class="Constant">2</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[def]</span>
-    <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
-    render-all screen, <span class="Constant">3</span>:&amp;:programming-environment-data, render
+    <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+    render-all screen, <span class="Constant">3</span>:&amp;:environment, render
   ]
   <span class="Comment"># divider isn't messed up</span>
   screen-should-contain [
@@ -423,12 +423,12 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   assume-screen <span class="Constant">30/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc]</span>
   <span class="Constant">2</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[def]</span>
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
-  render-all screen, <span class="Constant">3</span>:&amp;:programming-environment-data, render
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  render-all screen, <span class="Constant">3</span>:&amp;:environment, render
   <span class="Comment"># initialize programming environment and highlight cursor</span>
   assume-console <span class="Constant">[]</span>
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
     <span class="Constant">4</span>:char/cursor<span class="Special"> &lt;- </span>copy <span class="Constant">9251/␣</span>
     print screen:&amp;:screen, <span class="Constant">4</span>:char/cursor
   ]
@@ -444,7 +444,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     type <span class="Constant">[z]</span>
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
     <span class="Constant">4</span>:char/cursor<span class="Special"> &lt;- </span>copy <span class="Constant">9251/␣</span>
     print screen:&amp;:screen, <span class="Constant">4</span>:char/cursor
   ]
@@ -464,8 +464,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[]</span>
   <span class="Constant">2</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc</span>
 <span class="Constant">def]</span>
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
-  render-all screen, <span class="Constant">3</span>:&amp;:programming-environment-data, render
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  render-all screen, <span class="Constant">3</span>:&amp;:environment, render
   screen-should-contain [
    <span class="Constant"> .           run (F4)           .</span>
    <span class="Constant"> .               ┊abc           .</span>
@@ -479,7 +479,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press backspace
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
     <span class="Constant">4</span>:char/cursor<span class="Special"> &lt;- </span>copy <span class="Constant">9251/␣</span>
     print screen:&amp;:screen, <span class="Constant">4</span>:char/cursor
   ]
@@ -492,7 +492,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   ]
 ]
 
-<span class="muRecipe">def</span> render-all screen:&amp;:screen, env:&amp;:programming-environment-data, <span class="Delimiter">{</span>render-editor: (<span class="muRecipe">recipe</span> (address screen) (address editor-data)<span class="muRecipe"> -&gt; </span>number number (address screen) (address editor-data))<span class="Delimiter">}</span><span class="muRecipe"> -&gt; </span>screen:&amp;:screen, env:&amp;:programming-environment-data [
+<span class="muRecipe">def</span> render-all screen:&amp;:screen, env:&amp;:environment, <span class="Delimiter">{</span>render-editor: (<span class="muRecipe">recipe</span> (address screen) (address editor)<span class="muRecipe"> -&gt; </span>number number (address screen) (address editor))<span class="Delimiter">}</span><span class="muRecipe"> -&gt; </span>screen:&amp;:screen, env:&amp;:environment [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   trace <span class="Constant">10</span>, <span class="Constant">[app]</span>, <span class="Constant">[render all]</span>
@@ -516,19 +516,19 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   screen<span class="Special"> &lt;- </span>render-sandbox-side screen, env, render-editor
 <span class="Constant">  &lt;render-components-end&gt;</span>
   <span class="Comment">#</span>
-  recipes:&amp;:editor-data<span class="Special"> &lt;- </span>get *env, <span class="Constant">recipes:offset</span>
-  current-sandbox:&amp;:editor-data<span class="Special"> &lt;- </span>get *env, <span class="Constant">current-sandbox:offset</span>
+  recipes:&amp;:editor<span class="Special"> &lt;- </span>get *env, <span class="Constant">recipes:offset</span>
+  current-sandbox:&amp;:editor<span class="Special"> &lt;- </span>get *env, <span class="Constant">current-sandbox:offset</span>
   sandbox-in-focus?:bool<span class="Special"> &lt;- </span>get *env, <span class="Constant">sandbox-in-focus?:offset</span>
   screen<span class="Special"> &lt;- </span>update-cursor screen, recipes, current-sandbox, sandbox-in-focus?, env
   <span class="Comment">#</span>
   show-screen screen
 ]
 
-<span class="muRecipe">def</span> render-recipes screen:&amp;:screen, env:&amp;:programming-environment-data, <span class="Delimiter">{</span>render-editor: (<span class="muRecipe">recipe</span> (address screen) (address editor-data)<span class="muRecipe"> -&gt; </span>number number (address screen) (address editor-data))<span class="Delimiter">}</span><span class="muRecipe"> -&gt; </span>screen:&amp;:screen, env:&amp;:programming-environment-data [
+<span class="muRecipe">def</span> render-recipes screen:&amp;:screen, env:&amp;:environment, <span class="Delimiter">{</span>render-editor: (<span class="muRecipe">recipe</span> (address screen) (address editor)<span class="muRecipe"> -&gt; </span>number number (address screen) (address editor))<span class="Delimiter">}</span><span class="muRecipe"> -&gt; </span>screen:&amp;:screen, env:&amp;:environment [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   trace <span class="Constant">11</span>, <span class="Constant">[app]</span>, <span class="Constant">[render recipes]</span>
-  recipes:&amp;:editor-data<span class="Special"> &lt;- </span>get *env, <span class="Constant">recipes:offset</span>
+  recipes:&amp;:editor<span class="Special"> &lt;- </span>get *env, <span class="Constant">recipes:offset</span>
   <span class="Comment"># render recipes</span>
   left:num<span class="Special"> &lt;- </span>get *recipes, <span class="Constant">left:offset</span>
   right:num<span class="Special"> &lt;- </span>get *recipes, <span class="Constant">right:offset</span>
@@ -543,10 +543,10 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 ]
 
 <span class="Comment"># replaced in a later layer</span>
-<span class="muRecipe">def</span> render-sandbox-side screen:&amp;:screen, env:&amp;:programming-environment-data, <span class="Delimiter">{</span>render-editor: (<span class="muRecipe">recipe</span> (address screen) (address editor-data)<span class="muRecipe"> -&gt; </span>number number (address screen) (address editor-data))<span class="Delimiter">}</span><span class="muRecipe"> -&gt; </span>screen:&amp;:screen, env:&amp;:programming-environment-data [
+<span class="muRecipe">def</span> render-sandbox-side screen:&amp;:screen, env:&amp;:environment, <span class="Delimiter">{</span>render-editor: (<span class="muRecipe">recipe</span> (address screen) (address editor)<span class="muRecipe"> -&gt; </span>number number (address screen) (address editor))<span class="Delimiter">}</span><span class="muRecipe"> -&gt; </span>screen:&amp;:screen, env:&amp;:environment [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
-  current-sandbox:&amp;:editor-data<span class="Special"> &lt;- </span>get *env, <span class="Constant">current-sandbox:offset</span>
+  current-sandbox:&amp;:editor<span class="Special"> &lt;- </span>get *env, <span class="Constant">current-sandbox:offset</span>
   left:num<span class="Special"> &lt;- </span>get *current-sandbox, <span class="Constant">left:offset</span>
   right:num<span class="Special"> &lt;- </span>get *current-sandbox, <span class="Constant">right:offset</span>
   row:num, column:num, screen, current-sandbox<span class="Special"> &lt;- </span>call render-editor, screen, current-sandbox
@@ -558,7 +558,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   clear-screen-from screen, row, left, left, right
 ]
 
-<span class="muRecipe">def</span> update-cursor screen:&amp;:screen, recipes:&amp;:editor-data, current-sandbox:&amp;:editor-data, sandbox-in-focus?:bool, env:&amp;:programming-environment-data<span class="muRecipe"> -&gt; </span>screen:&amp;:screen [
+<span class="muRecipe">def</span> update-cursor screen:&amp;:screen, recipes:&amp;:editor, current-sandbox:&amp;:editor, sandbox-in-focus?:bool, env:&amp;:environment<span class="muRecipe"> -&gt; </span>screen:&amp;:screen [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
 <span class="Constant">  &lt;update-cursor-special-cases&gt;</span>
@@ -644,7 +644,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Delimiter">{</span>
     redraw-screen?:bool<span class="Special"> &lt;- </span>equal c, <span class="Constant">12/ctrl-l</span>
     <span class="muControl">break-unless</span> redraw-screen?
-    screen<span class="Special"> &lt;- </span>render-all screen, env:&amp;:programming-environment-data, render
+    screen<span class="Special"> &lt;- </span>render-all screen, env:&amp;:environment, render
     sync-screen screen
     <span class="muControl">loop</span> <span class="Constant">+next-event:label</span>
   <span class="Delimiter">}</span>
diff --git a/html/edit/005-sandbox.mu.html b/html/edit/005-sandbox.mu.html
index b6585eda..6aea4d1f 100644
--- a/html/edit/005-sandbox.mu.html
+++ b/html/edit/005-sandbox.mu.html
@@ -48,15 +48,15 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   initial-recipe:text<span class="Special"> &lt;- </span>restore <span class="Constant">[recipes.mu]</span>
   initial-sandbox:text<span class="Special"> &lt;- </span>new <span class="Constant">[]</span>
   hide-screen <span class="Constant">0/screen</span>
-  env:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment <span class="Constant">0/screen</span>, initial-recipe, initial-sandbox
+  env:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment <span class="Constant">0/screen</span>, initial-recipe, initial-sandbox
   env<span class="Special"> &lt;- </span>restore-sandboxes env
   render-all <span class="Constant">0/screen</span>, env, render
   event-loop <span class="Constant">0/screen</span>, <span class="Constant">0/console</span>, env
   <span class="Comment"># never gets here</span>
 ]
 
-<span class="muData">container</span> programming-environment-data [
-  sandbox:&amp;:sandbox-data  <span class="Comment"># list of sandboxes, from top to bottom</span>
+<span class="muData">container</span> environment [
+  sandbox:&amp;:sandbox  <span class="Comment"># list of sandboxes, from top to bottom</span>
   render-from:num
   number-of-sandboxes:num
 ]
@@ -65,7 +65,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   *result<span class="Special"> &lt;- </span>put *result, <span class="Constant">render-from:offset</span>, <span class="Constant">-1</span>
 ]
 
-<span class="muData">container</span> sandbox-data [
+<span class="muData">container</span> sandbox [
   data:text
   response:text
   <span class="Comment"># coordinates to track clicks</span>
@@ -73,7 +73,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   starting-row-on-screen:num
   code-ending-row-on-screen:num  <span class="Comment"># past end of code</span>
   screen:&amp;:screen  <span class="Comment"># prints in the sandbox go here</span>
-  next-sandbox:&amp;:sandbox-data
+  next-sandbox:&amp;:sandbox
 ]
 
 <span class="muScenario">scenario</span> run-and-show-results [
@@ -83,13 +83,13 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[]</span>
   <span class="Comment"># sandbox editor contains an instruction without storing outputs</span>
   <span class="Constant">2</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[divide-with-remainder 11, 3]</span>
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
   <span class="Comment"># run the code in the editors</span>
   assume-console [
     press F4
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   <span class="Comment"># check that screen prints the results</span>
   screen-should-contain [
@@ -139,7 +139,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press F4
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   <span class="Comment"># check that screen prints the results</span>
   screen-should-contain [
@@ -177,23 +177,23 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Delimiter">}</span>
 ]
 
-<span class="muRecipe">def</span> run-sandboxes env:&amp;:programming-environment-data, screen:&amp;:screen<span class="muRecipe"> -&gt; </span>errors-found?:bool, env:&amp;:programming-environment-data, screen:&amp;:screen [
+<span class="muRecipe">def</span> run-sandboxes env:&amp;:environment, screen:&amp;:screen<span class="muRecipe"> -&gt; </span>errors-found?:bool, env:&amp;:environment, screen:&amp;:screen [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   errors-found?:bool, env, screen<span class="Special"> &lt;- </span>update-recipes env, screen
   <span class="muControl">return-if</span> errors-found?
   <span class="Comment"># check contents of right editor (sandbox)</span>
 <span class="Constant">  &lt;run-sandboxes-begin&gt;</span>
-  current-sandbox:&amp;:editor-data<span class="Special"> &lt;- </span>get *env, <span class="Constant">current-sandbox:offset</span>
+  current-sandbox:&amp;:editor<span class="Special"> &lt;- </span>get *env, <span class="Constant">current-sandbox:offset</span>
   <span class="Delimiter">{</span>
     sandbox-contents:text<span class="Special"> &lt;- </span>editor-contents current-sandbox
     <span class="muControl">break-unless</span> sandbox-contents
     <span class="Comment"># if contents exist, first save them</span>
-    <span class="Comment"># run them and turn them into a new sandbox-data</span>
-    new-sandbox:&amp;:sandbox-data<span class="Special"> &lt;- </span>new <span class="Constant">sandbox-data:type</span>
+    <span class="Comment"># run them and turn them into a new sandbox</span>
+    new-sandbox:&amp;:sandbox<span class="Special"> &lt;- </span>new <span class="Constant">sandbox:type</span>
     *new-sandbox<span class="Special"> &lt;- </span>put *new-sandbox, <span class="Constant">data:offset</span>, sandbox-contents
     <span class="Comment"># push to head of sandbox list</span>
-    dest:&amp;:sandbox-data<span class="Special"> &lt;- </span>get *env, <span class="Constant">sandbox:offset</span>
+    dest:&amp;:sandbox<span class="Special"> &lt;- </span>get *env, <span class="Constant">sandbox:offset</span>
     *new-sandbox<span class="Special"> &lt;- </span>put *new-sandbox, <span class="Constant">next-sandbox:offset</span>, dest
     *env<span class="Special"> &lt;- </span>put *env, <span class="Constant">sandbox:offset</span>, new-sandbox
     <span class="Comment"># update sandbox count</span>
@@ -208,7 +208,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Comment"># save all sandboxes before running, just in case we die when running</span>
   save-sandboxes env
   <span class="Comment"># run all sandboxes</span>
-  curr:&amp;:sandbox-data<span class="Special"> &lt;- </span>get *env, <span class="Constant">sandbox:offset</span>
+  curr:&amp;:sandbox<span class="Special"> &lt;- </span>get *env, <span class="Constant">sandbox:offset</span>
   idx:num<span class="Special"> &lt;- </span>copy <span class="Constant">0</span>
   <span class="Delimiter">{</span>
     <span class="muControl">break-unless</span> curr
@@ -222,10 +222,10 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 
 <span class="Comment"># copy code from recipe editor, persist, load into mu</span>
 <span class="Comment"># replaced in a later layer (whereupon errors-found? will actually be set)</span>
-<span class="muRecipe">def</span> update-recipes env:&amp;:programming-environment-data, screen:&amp;:screen<span class="muRecipe"> -&gt; </span>errors-found?:bool, env:&amp;:programming-environment-data, screen:&amp;:screen [
+<span class="muRecipe">def</span> update-recipes env:&amp;:environment, screen:&amp;:screen<span class="muRecipe"> -&gt; </span>errors-found?:bool, env:&amp;:environment, screen:&amp;:screen [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
-  recipes:&amp;:editor-data<span class="Special"> &lt;- </span>get *env, <span class="Constant">recipes:offset</span>
+  recipes:&amp;:editor<span class="Special"> &lt;- </span>get *env, <span class="Constant">recipes:offset</span>
   in:text<span class="Special"> &lt;- </span>editor-contents recipes
   save <span class="Constant">[recipes.mu]</span>, in  <span class="Comment"># newlayer: persistence</span>
   reload in
@@ -233,7 +233,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 ]
 
 <span class="Comment"># replaced in a later layer</span>
-<span class="muRecipe">def!</span> update-sandbox sandbox:&amp;:sandbox-data, env:&amp;:programming-environment-data, idx:num<span class="muRecipe"> -&gt; </span>sandbox:&amp;:sandbox-data, env:&amp;:programming-environment-data [
+<span class="muRecipe">def!</span> update-sandbox sandbox:&amp;:sandbox, env:&amp;:environment, idx:num<span class="muRecipe"> -&gt; </span>sandbox:&amp;:sandbox, env:&amp;:environment [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   data:text<span class="Special"> &lt;- </span>get *sandbox, <span class="Constant">data:offset</span>
@@ -249,13 +249,13 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   screen<span class="Special"> &lt;- </span>print screen, msg, color, <span class="Constant">238/grey/background</span>
 ]
 
-<span class="muRecipe">def</span> save-sandboxes env:&amp;:programming-environment-data [
+<span class="muRecipe">def</span> save-sandboxes env:&amp;:environment [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
-  current-sandbox:&amp;:editor-data<span class="Special"> &lt;- </span>get *env, <span class="Constant">current-sandbox:offset</span>
+  current-sandbox:&amp;:editor<span class="Special"> &lt;- </span>get *env, <span class="Constant">current-sandbox:offset</span>
   <span class="Comment"># first clear previous versions, in case we deleted some sandbox</span>
   $system <span class="Constant">[rm lesson/[0-9]</span>* &gt;/dev/null <span class="Constant">2</span>&gt;/dev/null]  <span class="Comment"># some shells can't handle '&gt;&amp;'</span>
-  curr:&amp;:sandbox-data<span class="Special"> &lt;- </span>get *env, <span class="Constant">sandbox:offset</span>
+  curr:&amp;:sandbox<span class="Special"> &lt;- </span>get *env, <span class="Constant">sandbox:offset</span>
   idx:num<span class="Special"> &lt;- </span>copy <span class="Constant">0</span>
   <span class="Delimiter">{</span>
     <span class="muControl">break-unless</span> curr
@@ -269,11 +269,11 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Delimiter">}</span>
 ]
 
-<span class="muRecipe">def!</span> render-sandbox-side screen:&amp;:screen, env:&amp;:programming-environment-data, <span class="Delimiter">{</span>render-editor: (<span class="muRecipe">recipe</span> (address screen) (address editor-data)<span class="muRecipe"> -&gt; </span>number number (address screen) (address editor-data))<span class="Delimiter">}</span><span class="muRecipe"> -&gt; </span>screen:&amp;:screen, env:&amp;:programming-environment-data [
+<span class="muRecipe">def!</span> render-sandbox-side screen:&amp;:screen, env:&amp;:environment, <span class="Delimiter">{</span>render-editor: (<span class="muRecipe">recipe</span> (address screen) (address editor)<span class="muRecipe"> -&gt; </span>number number (address screen) (address editor))<span class="Delimiter">}</span><span class="muRecipe"> -&gt; </span>screen:&amp;:screen, env:&amp;:environment [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   trace <span class="Constant">11</span>, <span class="Constant">[app]</span>, <span class="Constant">[render sandbox side]</span>
-  current-sandbox:&amp;:editor-data<span class="Special"> &lt;- </span>get *env, <span class="Constant">current-sandbox:offset</span>
+  current-sandbox:&amp;:editor<span class="Special"> &lt;- </span>get *env, <span class="Constant">current-sandbox:offset</span>
   row:num, column:num<span class="Special"> &lt;- </span>copy <span class="Constant">1</span>, <span class="Constant">0</span>
   left:num<span class="Special"> &lt;- </span>get *current-sandbox, <span class="Constant">left:offset</span>
   right:num<span class="Special"> &lt;- </span>get *current-sandbox, <span class="Constant">right:offset</span>
@@ -288,12 +288,12 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Delimiter">}</span>
   <span class="Comment"># render sandboxes</span>
   draw-horizontal screen, row, left, right, <span class="Constant">9473/horizontal-double</span>
-  sandbox:&amp;:sandbox-data<span class="Special"> &lt;- </span>get *env, <span class="Constant">sandbox:offset</span>
+  sandbox:&amp;:sandbox<span class="Special"> &lt;- </span>get *env, <span class="Constant">sandbox:offset</span>
   row, screen<span class="Special"> &lt;- </span>render-sandboxes screen, sandbox, left, right, row, render-from
   clear-rest-of-screen screen, row, left, right
 ]
 
-<span class="muRecipe">def</span> render-sandboxes screen:&amp;:screen, sandbox:&amp;:sandbox-data, left:num, right:num, row:num, render-from:num, idx:num<span class="muRecipe"> -&gt; </span>row:num, screen:&amp;:screen, sandbox:&amp;:sandbox-data [
+<span class="muRecipe">def</span> render-sandboxes screen:&amp;:screen, sandbox:&amp;:sandbox, left:num, right:num, row:num, render-from:num, idx:num<span class="muRecipe"> -&gt; </span>row:num, screen:&amp;:screen, sandbox:&amp;:sandbox [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   <span class="muControl">return-unless</span> sandbox
@@ -343,7 +343,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="Constant">    &lt;end-render-sandbox-reset-hidden&gt;</span>
   <span class="Delimiter">}</span>
   <span class="Comment"># draw next sandbox</span>
-  next-sandbox:&amp;:sandbox-data<span class="Special"> &lt;- </span>get *sandbox, <span class="Constant">next-sandbox:offset</span>
+  next-sandbox:&amp;:sandbox<span class="Special"> &lt;- </span>get *sandbox, <span class="Constant">next-sandbox:offset</span>
   next-idx:num<span class="Special"> &lt;- </span>add idx, <span class="Constant">1</span>
   row, screen<span class="Special"> &lt;- </span>render-sandboxes screen, next-sandbox, left, right, row, render-from, next-idx
 ]
@@ -451,20 +451,20 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 ]
 
 <span class="Comment"># assumes programming environment has no sandboxes; restores them from previous session</span>
-<span class="muRecipe">def</span> restore-sandboxes env:&amp;:programming-environment-data<span class="muRecipe"> -&gt; </span>env:&amp;:programming-environment-data [
+<span class="muRecipe">def</span> restore-sandboxes env:&amp;:environment<span class="muRecipe"> -&gt; </span>env:&amp;:environment [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   <span class="Comment"># read all scenarios, pushing them to end of a list of scenarios</span>
   idx:num<span class="Special"> &lt;- </span>copy <span class="Constant">0</span>
-  curr:&amp;:sandbox-data<span class="Special"> &lt;- </span>copy <span class="Constant">0</span>
-  prev:&amp;:sandbox-data<span class="Special"> &lt;- </span>copy <span class="Constant">0</span>
+  curr:&amp;:sandbox<span class="Special"> &lt;- </span>copy <span class="Constant">0</span>
+  prev:&amp;:sandbox<span class="Special"> &lt;- </span>copy <span class="Constant">0</span>
   <span class="Delimiter">{</span>
     filename:text<span class="Special"> &lt;- </span>to-text idx
     contents:text<span class="Special"> &lt;- </span>restore filename
     <span class="muControl">break-unless</span> contents  <span class="Comment"># stop at first error; assuming file didn't exist</span>
                            <span class="Comment"># todo: handle empty sandbox</span>
     <span class="Comment"># create new sandbox for file</span>
-    curr<span class="Special"> &lt;- </span>new <span class="Constant">sandbox-data:type</span>
+    curr<span class="Special"> &lt;- </span>new <span class="Constant">sandbox:type</span>
     *curr<span class="Special"> &lt;- </span>put *curr, <span class="Constant">data:offset</span>, contents
 <span class="Constant">    &lt;end-restore-sandbox&gt;</span>
     <span class="Delimiter">{</span>
@@ -562,12 +562,12 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="Constant">]</span>]
   <span class="Comment"># sandbox editor contains an instruction without storing outputs</span>
   <span class="Constant">2</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[foo]</span>
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
   <span class="Comment"># run the code in the editors</span>
   assume-console [
     press F4
   ]
-  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   screen-should-contain [
    <span class="Constant"> .                                                                                 run (F4)           .</span>
    <span class="Constant"> .                                                  ┊                                                 .</span>
@@ -587,7 +587,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press F4
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   <span class="Comment"># check that screen updates the result on the right</span>
   screen-should-contain [
@@ -610,13 +610,13 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[]</span>
   <span class="Comment"># right editor contains an instruction</span>
   <span class="Constant">2</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[print-integer screen, 4]</span>
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
   <span class="Comment"># run the code in the editor</span>
   assume-console [
     press F4
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   <span class="Comment"># check that it prints a little toy screen</span>
   screen-should-contain [
@@ -636,7 +636,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   ]
 ]
 
-<span class="muRecipe">def</span> editor-contents editor:&amp;:editor-data<span class="muRecipe"> -&gt; </span>result:text [
+<span class="muRecipe">def</span> editor-contents editor:&amp;:editor<span class="muRecipe"> -&gt; </span>result:text [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   buf:&amp;:buffer<span class="Special"> &lt;- </span>new-buffer <span class="Constant">80</span>
@@ -658,14 +658,14 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="muScenario">scenario</span> editor-provides-edited-contents [
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
   assume-console [
     left-click <span class="Constant">1</span>, <span class="Constant">2</span>
     type <span class="Constant">[def]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:text<span class="Special"> &lt;- </span>editor-contents <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:text<span class="Special"> &lt;- </span>editor-contents <span class="Constant">2</span>:&amp;:editor
     <span class="Constant">4</span>:@:char<span class="Special"> &lt;- </span>copy *<span class="Constant">3</span>:text
   ]
   memory-should-contain [
@@ -679,7 +679,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Constant">local-scope</span>
   trace-until <span class="Constant">100/app</span>
   assume-screen <span class="Constant">100/width</span>, <span class="Constant">10/height</span>
-  env:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">[]</span>, <span class="Constant">[]</span>
+  env:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">[]</span>, <span class="Constant">[]</span>
   render-all screen, env, render
   assume-console [
     press enter
@@ -700,7 +700,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Constant">local-scope</span>
   trace-until <span class="Constant">100/app</span>
   assume-screen <span class="Constant">100/width</span>, <span class="Constant">10/height</span>
-  env:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">[]</span>, <span class="Constant">[]</span>
+  env:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">[]</span>, <span class="Constant">[]</span>
   render-all screen, env, render
   assume-console [
     press enter
@@ -723,7 +723,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="Comment"># we'll not use the recipe-editor's 'bottom' element directly, because later</span>
 <span class="Comment"># layers will add other stuff to the left side below the editor (error messages)</span>
 
-<span class="muData">container</span> programming-environment-data [
+<span class="muData">container</span> environment [
   recipe-bottom:num
 ]
 
@@ -736,7 +736,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     <span class="muControl">break-if</span> sandbox-in-focus?
     down-arrow?:bool<span class="Special"> &lt;- </span>equal k, <span class="Constant">65516/down-arrow</span>
     <span class="muControl">break-unless</span> down-arrow?
-    recipe-editor:&amp;:editor-data<span class="Special"> &lt;- </span>get *env, <span class="Constant">recipes:offset</span>
+    recipe-editor:&amp;:editor<span class="Special"> &lt;- </span>get *env, <span class="Constant">recipes:offset</span>
     recipe-cursor-row:num<span class="Special"> &lt;- </span>get *recipe-editor, <span class="Constant">cursor-row:offset</span>
     recipe-editor-bottom:num<span class="Special"> &lt;- </span>get *recipe-editor, <span class="Constant">bottom:offset</span>
     at-bottom-of-editor?:bool<span class="Special"> &lt;- </span>greater-or-equal recipe-cursor-row, recipe-editor-bottom
@@ -766,7 +766,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Delimiter">}</span>
 ]
 
-<span class="muRecipe">def</span> more-to-scroll? env:&amp;:programming-environment-data, screen:&amp;:screen<span class="muRecipe"> -&gt; </span>result:bool [
+<span class="muRecipe">def</span> more-to-scroll? env:&amp;:environment, screen:&amp;:screen<span class="muRecipe"> -&gt; </span>result:bool [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   recipe-bottom:num<span class="Special"> &lt;- </span>get *env, <span class="Constant">recipe-bottom:offset</span>
@@ -778,7 +778,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Constant">local-scope</span>
   trace-until <span class="Constant">100/app</span>
   assume-screen <span class="Constant">100/width</span>, <span class="Constant">10/height</span>
-  env:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">[]</span>, <span class="Constant">[]</span>
+  env:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">[]</span>, <span class="Constant">[]</span>
   render-all screen, env, render
   assume-console [
     <span class="Comment"># add a line</span>
@@ -803,7 +803,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Constant">local-scope</span>
   trace-until <span class="Constant">100/app</span>
   assume-screen <span class="Constant">100/width</span>, <span class="Constant">10/height</span>
-  env:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">[]</span>, <span class="Constant">[ab</span>
+  env:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">[]</span>, <span class="Constant">[ab</span>
 <span class="Constant">cd]</span>
   render-all screen, env, render
   assume-console [
@@ -835,13 +835,13 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Comment"># initialize sandbox side</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[]</span>
   <span class="Constant">2</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[add 2, 2]</span>
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
-  render-all screen, <span class="Constant">3</span>:&amp;:programming-environment-data, render
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  render-all screen, <span class="Constant">3</span>:&amp;:environment, render
   assume-console [
     <span class="Comment"># create a sandbox</span>
     press F4
   ]
-  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   screen-should-contain [
    <span class="Constant"> .                                                                                 run (F4)           .</span>
    <span class="Constant"> .                                                  ┊                                                 .</span>
@@ -855,7 +855,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press page-down
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
     <span class="Constant">4</span>:char/cursor<span class="Special"> &lt;- </span>copy <span class="Constant">9251/␣</span>
     print screen:&amp;:screen, <span class="Constant">4</span>:char/cursor
   ]
@@ -873,7 +873,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press page-up
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
     <span class="Constant">4</span>:char/cursor<span class="Special"> &lt;- </span>copy <span class="Constant">9251/␣</span>
     print screen:&amp;:screen, <span class="Constant">4</span>:char/cursor
   ]
@@ -893,7 +893,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     <span class="muControl">break-unless</span> sandbox-in-focus?
     page-down?:bool<span class="Special"> &lt;- </span>equal k, <span class="Constant">65518/page-down</span>
     <span class="muControl">break-unless</span> page-down?
-    sandbox:&amp;:sandbox-data<span class="Special"> &lt;- </span>get *env, <span class="Constant">sandbox:offset</span>
+    sandbox:&amp;:sandbox<span class="Special"> &lt;- </span>get *env, <span class="Constant">sandbox:offset</span>
     <span class="muControl">break-unless</span> sandbox
     <span class="Comment"># slide down if possible</span>
     <span class="Delimiter">{</span>
@@ -945,12 +945,12 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 
 <span class="Comment"># sandbox belonging to 'env' whose next-sandbox is 'in'</span>
 <span class="Comment"># return 0 if there's no such sandbox, either because 'in' doesn't exist in 'env', or because it's the first sandbox</span>
-<span class="muRecipe">def</span> previous-sandbox env:&amp;:programming-environment-data, in:&amp;:sandbox-data<span class="muRecipe"> -&gt; </span>out:&amp;:sandbox-data [
+<span class="muRecipe">def</span> previous-sandbox env:&amp;:environment, in:&amp;:sandbox<span class="muRecipe"> -&gt; </span>out:&amp;:sandbox [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
-  curr:&amp;:sandbox-data<span class="Special"> &lt;- </span>get *env, <span class="Constant">sandbox:offset</span>
+  curr:&amp;:sandbox<span class="Special"> &lt;- </span>get *env, <span class="Constant">sandbox:offset</span>
   <span class="muControl">return-unless</span> curr, <span class="Constant">0/nil</span>
-  next:&amp;:sandbox-data<span class="Special"> &lt;- </span>get *curr, <span class="Constant">next-sandbox:offset</span>
+  next:&amp;:sandbox<span class="Special"> &lt;- </span>get *curr, <span class="Constant">next-sandbox:offset</span>
   <span class="Delimiter">{</span>
     <span class="muControl">return-unless</span> next, <span class="Constant">0/nil</span>
     found?:bool<span class="Special"> &lt;- </span>equal next, in
@@ -970,18 +970,18 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="Constant">]</span>
   <span class="Comment"># create a sandbox</span>
   <span class="Constant">2</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[add 2, 2]</span>
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
-  render-all screen, <span class="Constant">3</span>:&amp;:programming-environment-data, render
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  render-all screen, <span class="Constant">3</span>:&amp;:environment, render
   assume-console [
     press F4
   ]
-  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   <span class="Comment"># hit 'down' in recipe editor</span>
   assume-console [
     press page-down
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
     <span class="Constant">4</span>:char/cursor<span class="Special"> &lt;- </span>copy <span class="Constant">9251/␣</span>
     print screen:&amp;:screen, <span class="Constant">4</span>:char/cursor
   ]
@@ -1001,8 +1001,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Comment"># initialize environment</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[]</span>
   <span class="Constant">2</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[]</span>
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
-  render-all screen, <span class="Constant">3</span>:&amp;:programming-environment-data, render
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  render-all screen, <span class="Constant">3</span>:&amp;:environment, render
   <span class="Comment"># create 2 sandboxes</span>
   assume-console [
     press ctrl-n
@@ -1011,7 +1011,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     type <span class="Constant">[add 1, 1]</span>
     press F4
   ]
-  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   <span class="Constant">4</span>:char/cursor<span class="Special"> &lt;- </span>copy <span class="Constant">9251/␣</span>
   print screen:&amp;:screen, <span class="Constant">4</span>:char/cursor
   screen-should-contain [
@@ -1031,7 +1031,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press page-down
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
     <span class="Constant">4</span>:char/cursor<span class="Special"> &lt;- </span>copy <span class="Constant">9251/␣</span>
     print screen:&amp;:screen, <span class="Constant">4</span>:char/cursor
   ]
@@ -1053,7 +1053,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press page-down
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   <span class="Comment"># just second sandbox displayed</span>
   screen-should-contain [
@@ -1070,7 +1070,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press page-down
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   <span class="Comment"># no change</span>
   screen-should-contain [
@@ -1087,7 +1087,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press page-up
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   <span class="Comment"># back to displaying both sandboxes without editor</span>
   screen-should-contain [
@@ -1106,7 +1106,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press page-up
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
     <span class="Constant">4</span>:char/cursor<span class="Special"> &lt;- </span>copy <span class="Constant">9251/␣</span>
     print screen:&amp;:screen, <span class="Constant">4</span>:char/cursor
   ]
@@ -1128,7 +1128,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press page-up
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
     <span class="Constant">4</span>:char/cursor<span class="Special"> &lt;- </span>copy <span class="Constant">9251/␣</span>
     print screen:&amp;:screen, <span class="Constant">4</span>:char/cursor
   ]
@@ -1153,15 +1153,15 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Comment"># initialize environment</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[]</span>
   <span class="Constant">2</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[]</span>
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
-  render-all screen, <span class="Constant">3</span>:&amp;:programming-environment-data, render
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  render-all screen, <span class="Constant">3</span>:&amp;:environment, render
   <span class="Comment"># create a sandbox</span>
   assume-console [
     press ctrl-n
     type <span class="Constant">[add 1, 1]</span>
     press F4
   ]
-  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   screen-should-contain [
    <span class="Constant"> .                                                                                 run (F4)           .</span>
    <span class="Constant"> .                                                  ┊                                                 .</span>
@@ -1177,7 +1177,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press page-down
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   <span class="Comment"># sandbox editor hidden; first sandbox displayed</span>
   <span class="Comment"># cursor moves to first sandbox</span>
@@ -1195,7 +1195,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press page-up
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   <span class="Comment"># back to displaying both sandboxes as well as editor</span>
   screen-should-contain [
@@ -1213,7 +1213,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press page-down
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   <span class="Comment"># sandbox editor hidden; first sandbox displayed</span>
   <span class="Comment"># cursor moves to first sandbox</span>
diff --git a/html/edit/006-sandbox-copy.mu.html b/html/edit/006-sandbox-copy.mu.html
index 987f38f9..dd5adf80 100644
--- a/html/edit/006-sandbox-copy.mu.html
+++ b/html/edit/006-sandbox-copy.mu.html
@@ -48,8 +48,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   assume-console [
     press F4
   ]
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
-  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   screen-should-contain [
    <span class="Constant"> .                                                                                 run (F4)           .</span>
    <span class="Constant"> .                                                  ┊                                                 .</span>
@@ -65,7 +65,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     left-click <span class="Constant">3</span>, <span class="Constant">69</span>
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   <span class="Comment"># it copies into editor</span>
   screen-should-contain [
@@ -83,7 +83,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     type <span class="Constant">[0]</span>
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   screen-should-contain [
    <span class="Constant"> .                                                                                 run (F4)           .</span>
@@ -110,8 +110,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   assume-console [
     press F4
   ]
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
-  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   screen-should-contain [
    <span class="Constant"> .                                                                                 run (F4)           .</span>
    <span class="Constant"> .                                                  ┊                                                 .</span>
@@ -127,7 +127,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     left-click <span class="Constant">3</span>, <span class="Constant">84</span>
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   <span class="Comment"># it copies into editor</span>
   screen-should-contain [
@@ -145,7 +145,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     type <span class="Constant">[0]</span>
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   screen-should-contain [
    <span class="Constant"> .                                                                                 run (F4)           .</span>
@@ -175,14 +175,14 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 ]
 
 <span class="Comment"># some preconditions for attempting to copy a sandbox</span>
-<span class="muRecipe">def</span> should-attempt-copy? click-row:num, click-column:num, env:&amp;:programming-environment-data<span class="muRecipe"> -&gt; </span>result:bool [
+<span class="muRecipe">def</span> should-attempt-copy? click-row:num, click-column:num, env:&amp;:environment<span class="muRecipe"> -&gt; </span>result:bool [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   <span class="Comment"># are we below the sandbox editor?</span>
   click-sandbox-area?:bool<span class="Special"> &lt;- </span>click-on-sandbox-area? click-row, click-column, env
   <span class="muControl">reply-unless</span> click-sandbox-area?, <span class="Constant">0/false</span>
   <span class="Comment"># narrower, is the click in the columns spanning the 'copy' button?</span>
-  first-sandbox:&amp;:editor-data<span class="Special"> &lt;- </span>get *env, <span class="Constant">current-sandbox:offset</span>
+  first-sandbox:&amp;:editor<span class="Special"> &lt;- </span>get *env, <span class="Constant">current-sandbox:offset</span>
   assert first-sandbox, <span class="Constant">[!!]</span>
   sandbox-left-margin:num<span class="Special"> &lt;- </span>get *first-sandbox, <span class="Constant">left:offset</span>
   sandbox-right-margin:num<span class="Special"> &lt;- </span>get *first-sandbox, <span class="Constant">right:offset</span>
@@ -190,19 +190,19 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   copy-button-vertical-area?:bool<span class="Special"> &lt;- </span>within-range? click-column, copy-button-left, copy-button-right
   <span class="muControl">reply-unless</span> copy-button-vertical-area?, <span class="Constant">0/false</span>
   <span class="Comment"># finally, is sandbox editor empty?</span>
-  current-sandbox:&amp;:editor-data<span class="Special"> &lt;- </span>get *env, <span class="Constant">current-sandbox:offset</span>
+  current-sandbox:&amp;:editor<span class="Special"> &lt;- </span>get *env, <span class="Constant">current-sandbox:offset</span>
   result<span class="Special"> &lt;- </span>empty-editor? current-sandbox
 ]
 
-<span class="muRecipe">def</span> try-copy-sandbox click-row:num, env:&amp;:programming-environment-data<span class="muRecipe"> -&gt; </span>clicked-on-copy-button?:bool, env:&amp;:programming-environment-data [
+<span class="muRecipe">def</span> try-copy-sandbox click-row:num, env:&amp;:environment<span class="muRecipe"> -&gt; </span>clicked-on-copy-button?:bool, env:&amp;:environment [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   <span class="Comment"># identify the sandbox to copy, if the click was actually on the 'copy' button</span>
-  sandbox:&amp;:sandbox-data<span class="Special"> &lt;- </span>find-sandbox env, click-row
+  sandbox:&amp;:sandbox<span class="Special"> &lt;- </span>find-sandbox env, click-row
   <span class="muControl">return-unless</span> sandbox, <span class="Constant">0/false</span>
   clicked-on-copy-button?<span class="Special"> &lt;- </span>copy <span class="Constant">1/true</span>
   text:text<span class="Special"> &lt;- </span>get *sandbox, <span class="Constant">data:offset</span>
-  current-sandbox:&amp;:editor-data<span class="Special"> &lt;- </span>get *env, <span class="Constant">current-sandbox:offset</span>
+  current-sandbox:&amp;:editor<span class="Special"> &lt;- </span>get *env, <span class="Constant">current-sandbox:offset</span>
   current-sandbox<span class="Special"> &lt;- </span>insert-text current-sandbox, text
   <span class="Comment"># reset scroll</span>
   *env<span class="Special"> &lt;- </span>put *env, <span class="Constant">render-from:offset</span>, <span class="Constant">-1</span>
@@ -210,10 +210,10 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   *env<span class="Special"> &lt;- </span>put *env, <span class="Constant">sandbox-in-focus?:offset</span>, <span class="Constant">1/true</span>
 ]
 
-<span class="muRecipe">def</span> find-sandbox env:&amp;:programming-environment-data, click-row:num<span class="muRecipe"> -&gt; </span>result:&amp;:sandbox-data [
+<span class="muRecipe">def</span> find-sandbox env:&amp;:environment, click-row:num<span class="muRecipe"> -&gt; </span>result:&amp;:sandbox [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
-  curr-sandbox:&amp;:sandbox-data<span class="Special"> &lt;- </span>get *env, <span class="Constant">sandbox:offset</span>
+  curr-sandbox:&amp;:sandbox<span class="Special"> &lt;- </span>get *env, <span class="Constant">sandbox:offset</span>
   <span class="Delimiter">{</span>
     <span class="muControl">break-unless</span> curr-sandbox
     start:num<span class="Special"> &lt;- </span>get *curr-sandbox, <span class="Constant">starting-row-on-screen:offset</span>
@@ -225,20 +225,20 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="muControl">return</span> <span class="Constant">0/not-found</span>
 ]
 
-<span class="muRecipe">def</span> click-on-sandbox-area? click-row:num, click-column:num, env:&amp;:programming-environment-data<span class="muRecipe"> -&gt; </span>result:bool [
+<span class="muRecipe">def</span> click-on-sandbox-area? click-row:num, click-column:num, env:&amp;:environment<span class="muRecipe"> -&gt; </span>result:bool [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
-  current-sandbox:&amp;:editor-data<span class="Special"> &lt;- </span>get *env, <span class="Constant">current-sandbox:offset</span>
+  current-sandbox:&amp;:editor<span class="Special"> &lt;- </span>get *env, <span class="Constant">current-sandbox:offset</span>
   sandbox-left-margin:num<span class="Special"> &lt;- </span>get *current-sandbox, <span class="Constant">left:offset</span>
   on-sandbox-side?:bool<span class="Special"> &lt;- </span>greater-or-equal click-column, sandbox-left-margin
   <span class="muControl">return-unless</span> on-sandbox-side?, <span class="Constant">0/false</span>
-  first-sandbox:&amp;:sandbox-data<span class="Special"> &lt;- </span>get *env, <span class="Constant">sandbox:offset</span>
+  first-sandbox:&amp;:sandbox<span class="Special"> &lt;- </span>get *env, <span class="Constant">sandbox:offset</span>
   <span class="muControl">return-unless</span> first-sandbox, <span class="Constant">0/false</span>
   first-sandbox-begins:num<span class="Special"> &lt;- </span>get *first-sandbox, <span class="Constant">starting-row-on-screen:offset</span>
   result<span class="Special"> &lt;- </span>greater-or-equal click-row, first-sandbox-begins
 ]
 
-<span class="muRecipe">def</span> empty-editor? editor:&amp;:editor-data<span class="muRecipe"> -&gt; </span>result:bool [
+<span class="muRecipe">def</span> empty-editor? editor:&amp;:editor<span class="muRecipe"> -&gt; </span>result:bool [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   head:&amp;:duplex-list:char<span class="Special"> &lt;- </span>get *editor, <span class="Constant">data:offset</span>
@@ -267,8 +267,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   assume-console [
     press F4
   ]
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
-  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   screen-should-contain [
    <span class="Constant"> .                                                                                 run (F4)           .</span>
    <span class="Constant"> .                                                  ┊                                                 .</span>
@@ -286,7 +286,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     left-click <span class="Constant">3</span>, <span class="Constant">70</span>  <span class="Comment"># click 'copy' button</span>
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   <span class="Comment"># copy doesn't happen</span>
   screen-should-contain [
@@ -304,7 +304,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     type <span class="Constant">[1]</span>
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   screen-should-contain [
    <span class="Constant"> .                                                                                 run (F4)           .</span>
diff --git a/html/edit/007-sandbox-delete.mu.html b/html/edit/007-sandbox-delete.mu.html
index 668faca9..21cb2be6 100644
--- a/html/edit/007-sandbox-delete.mu.html
+++ b/html/edit/007-sandbox-delete.mu.html
@@ -39,7 +39,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   assume-screen <span class="Constant">100/width</span>, <span class="Constant">15/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[]</span>
   <span class="Constant">2</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[]</span>
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
   <span class="Comment"># run a few commands</span>
   assume-console [
     left-click <span class="Constant">1</span>, <span class="Constant">80</span>
@@ -48,7 +48,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     type <span class="Constant">[add 2, 2]</span>
     press F4
   ]
-  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   screen-should-contain [
    <span class="Constant"> .                                                                                 run (F4)           .</span>
    <span class="Constant"> .                                                  ┊                                                 .</span>
@@ -69,7 +69,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     left-click <span class="Constant">7</span>, <span class="Constant">85</span>
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   screen-should-contain [
    <span class="Constant"> .                                                                                 run (F4)           .</span>
@@ -87,7 +87,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     left-click <span class="Constant">3</span>, <span class="Constant">99</span>
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   screen-should-contain [
    <span class="Constant"> .                                                                                 run (F4)           .</span>
@@ -114,14 +114,14 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 ]
 
 <span class="Comment"># some preconditions for attempting to delete a sandbox</span>
-<span class="muRecipe">def</span> should-attempt-delete? click-row:num, click-column:num, env:&amp;:programming-environment-data<span class="muRecipe"> -&gt; </span>result:bool [
+<span class="muRecipe">def</span> should-attempt-delete? click-row:num, click-column:num, env:&amp;:environment<span class="muRecipe"> -&gt; </span>result:bool [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   <span class="Comment"># are we below the sandbox editor?</span>
   click-sandbox-area?:bool<span class="Special"> &lt;- </span>click-on-sandbox-area? click-row, click-column, env
   <span class="muControl">reply-unless</span> click-sandbox-area?, <span class="Constant">0/false</span>
   <span class="Comment"># narrower, is the click in the columns spanning the 'copy' button?</span>
-  first-sandbox:&amp;:editor-data<span class="Special"> &lt;- </span>get *env, <span class="Constant">current-sandbox:offset</span>
+  first-sandbox:&amp;:editor<span class="Special"> &lt;- </span>get *env, <span class="Constant">current-sandbox:offset</span>
   assert first-sandbox, <span class="Constant">[!!]</span>
   sandbox-left-margin:num<span class="Special"> &lt;- </span>get *first-sandbox, <span class="Constant">left:offset</span>
   sandbox-right-margin:num<span class="Special"> &lt;- </span>get *first-sandbox, <span class="Constant">right:offset</span>
@@ -129,31 +129,31 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   result<span class="Special"> &lt;- </span>within-range? click-column, delete-button-left, sandbox-right-margin
 ]
 
-<span class="muRecipe">def</span> try-delete-sandbox click-row:num, env:&amp;:programming-environment-data<span class="muRecipe"> -&gt; </span>clicked-on-delete-button?:bool, env:&amp;:programming-environment-data [
+<span class="muRecipe">def</span> try-delete-sandbox click-row:num, env:&amp;:environment<span class="muRecipe"> -&gt; </span>clicked-on-delete-button?:bool, env:&amp;:environment [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   <span class="Comment"># identify the sandbox to delete, if the click was actually on the 'delete' button</span>
-  sandbox:&amp;:sandbox-data<span class="Special"> &lt;- </span>find-sandbox env, click-row
+  sandbox:&amp;:sandbox<span class="Special"> &lt;- </span>find-sandbox env, click-row
   <span class="muControl">return-unless</span> sandbox, <span class="Constant">0/false</span>
   clicked-on-delete-button?<span class="Special"> &lt;- </span>copy <span class="Constant">1/true</span>
   env<span class="Special"> &lt;- </span>delete-sandbox env, sandbox
 ]
 
-<span class="muRecipe">def</span> delete-sandbox env:&amp;:programming-environment-data, sandbox:&amp;:sandbox-data<span class="muRecipe"> -&gt; </span>env:&amp;:programming-environment-data [
+<span class="muRecipe">def</span> delete-sandbox env:&amp;:environment, sandbox:&amp;:sandbox<span class="muRecipe"> -&gt; </span>env:&amp;:environment [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
-  curr-sandbox:&amp;:sandbox-data<span class="Special"> &lt;- </span>get *env, <span class="Constant">sandbox:offset</span>
+  curr-sandbox:&amp;:sandbox<span class="Special"> &lt;- </span>get *env, <span class="Constant">sandbox:offset</span>
   first-sandbox?:bool<span class="Special"> &lt;- </span>equal curr-sandbox, sandbox
   <span class="Delimiter">{</span>
     <span class="Comment"># first sandbox? pop</span>
     <span class="muControl">break-unless</span> first-sandbox?
-    next-sandbox:&amp;:sandbox-data<span class="Special"> &lt;- </span>get *curr-sandbox, <span class="Constant">next-sandbox:offset</span>
+    next-sandbox:&amp;:sandbox<span class="Special"> &lt;- </span>get *curr-sandbox, <span class="Constant">next-sandbox:offset</span>
     *env<span class="Special"> &lt;- </span>put *env, <span class="Constant">sandbox:offset</span>, next-sandbox
   <span class="Delimiter">}</span>
   <span class="Delimiter">{</span>
     <span class="Comment"># not first sandbox?</span>
     <span class="muControl">break-if</span> first-sandbox?
-    prev-sandbox:&amp;:sandbox-data<span class="Special"> &lt;- </span>copy curr-sandbox
+    prev-sandbox:&amp;:sandbox<span class="Special"> &lt;- </span>copy curr-sandbox
     curr-sandbox<span class="Special"> &lt;- </span>get *curr-sandbox, <span class="Constant">next-sandbox:offset</span>
     <span class="Delimiter">{</span>
       assert curr-sandbox, <span class="Constant">[sandbox not found! something is wrong.]</span>
@@ -164,7 +164,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
       <span class="muControl">loop</span>
     <span class="Delimiter">}</span>
     <span class="Comment"># snip sandbox out of its list</span>
-    next-sandbox:&amp;:sandbox-data<span class="Special"> &lt;- </span>get *curr-sandbox, <span class="Constant">next-sandbox:offset</span>
+    next-sandbox:&amp;:sandbox<span class="Special"> &lt;- </span>get *curr-sandbox, <span class="Constant">next-sandbox:offset</span>
     *prev-sandbox<span class="Special"> &lt;- </span>put *prev-sandbox, <span class="Constant">next-sandbox:offset</span>, next-sandbox
   <span class="Delimiter">}</span>
   <span class="Comment"># update sandbox count</span>
@@ -187,8 +187,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Comment"># initialize environment</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[]</span>
   <span class="Constant">2</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[]</span>
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
-  render-all screen, <span class="Constant">3</span>:&amp;:programming-environment-data, render
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  render-all screen, <span class="Constant">3</span>:&amp;:environment, render
   <span class="Comment"># create 2 sandboxes and scroll to second</span>
   assume-console [
     press ctrl-n
@@ -198,7 +198,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press F4
     press page-down
   ]
-  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   screen-should-contain [
    <span class="Constant"> .                                                                                 run (F4)           .</span>
    <span class="Constant"> .                                                  ┊━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━.</span>
@@ -213,7 +213,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     left-click <span class="Constant">6</span>, <span class="Constant">99</span>
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   <span class="Comment"># second sandbox shows in editor; scroll resets to display first sandbox</span>
   screen-should-contain [
@@ -233,8 +233,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Comment"># initialize environment</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[]</span>
   <span class="Constant">2</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[]</span>
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
-  render-all screen, <span class="Constant">3</span>:&amp;:programming-environment-data, render
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  render-all screen, <span class="Constant">3</span>:&amp;:environment, render
   <span class="Comment"># create 2 sandboxes and scroll to second</span>
   assume-console [
     press ctrl-n
@@ -244,7 +244,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press F4
     press page-down
   ]
-  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   screen-should-contain [
    <span class="Constant"> .                                                                                 run (F4)           .</span>
    <span class="Constant"> .                                                  ┊━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━.</span>
@@ -259,7 +259,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     left-click <span class="Constant">2</span>, <span class="Constant">99</span>
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   <span class="Comment"># second sandbox shows in editor; scroll resets to display first sandbox</span>
   screen-should-contain [
@@ -279,8 +279,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Comment"># initialize environment</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[]</span>
   <span class="Constant">2</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[]</span>
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
-  render-all screen, <span class="Constant">3</span>:&amp;:programming-environment-data, render
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  render-all screen, <span class="Constant">3</span>:&amp;:environment, render
   <span class="Comment"># create 2 sandboxes and scroll to second</span>
   assume-console [
     press ctrl-n
@@ -291,7 +291,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press page-down
     press page-down
   ]
-  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   screen-should-contain [
    <span class="Constant"> .                                                                                 run (F4)           .</span>
    <span class="Constant"> .                                                  ┊━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━.</span>
@@ -306,7 +306,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     left-click <span class="Constant">2</span>, <span class="Constant">99</span>
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   <span class="Comment"># implicitly scroll up to first sandbox</span>
   screen-should-contain [
@@ -327,8 +327,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Comment"># initialize environment</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[]</span>
   <span class="Constant">2</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[]</span>
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
-  render-all screen, <span class="Constant">3</span>:&amp;:programming-environment-data, render
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  render-all screen, <span class="Constant">3</span>:&amp;:environment, render
   <span class="Comment"># create 2 sandboxes</span>
   assume-console [
     press ctrl-n
@@ -337,7 +337,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     type <span class="Constant">[add 1, 1]</span>
     press F4
   ]
-  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   screen-should-contain [
    <span class="Constant"> .                                                                                 run (F4)           .</span>
    <span class="Constant"> .                                                  ┊                                                 .</span>
@@ -357,7 +357,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press page-down
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   <span class="Comment"># shouldn't go past last sandbox</span>
   screen-should-contain [
diff --git a/html/edit/008-sandbox-edit.mu.html b/html/edit/008-sandbox-edit.mu.html
index 1fcf071f..b7fbe660 100644
--- a/html/edit/008-sandbox-edit.mu.html
+++ b/html/edit/008-sandbox-edit.mu.html
@@ -47,8 +47,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   assume-console [
     press F4
   ]
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
-  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   screen-should-contain [
    <span class="Constant"> .                                                                                 run (F4)           .</span>
    <span class="Constant"> .                                                  ┊                                                 .</span>
@@ -64,7 +64,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     left-click <span class="Constant">3</span>, <span class="Constant">55</span>
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   <span class="Comment"># it pops back into editor</span>
   screen-should-contain [
@@ -81,7 +81,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     type <span class="Constant">[0]</span>
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   screen-should-contain [
    <span class="Constant"> .                                                                                 run (F4)           .</span>
@@ -107,8 +107,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   assume-console [
     press F4
   ]
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
-  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   screen-should-contain [
    <span class="Constant"> .                                                                                 run (F4)           .</span>
    <span class="Constant"> .                                                  ┊                                                 .</span>
@@ -124,7 +124,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     left-click <span class="Constant">3</span>, <span class="Constant">68</span>
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   <span class="Comment"># it pops back into editor</span>
   screen-should-contain [
@@ -141,7 +141,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     type <span class="Constant">[0]</span>
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   screen-should-contain [
    <span class="Constant"> .                                                                                 run (F4)           .</span>
@@ -170,14 +170,14 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 ]
 
 <span class="Comment"># some preconditions for attempting to edit a sandbox</span>
-<span class="muRecipe">def</span> should-attempt-edit? click-row:num, click-column:num, env:&amp;:programming-environment-data<span class="muRecipe"> -&gt; </span>result:bool [
+<span class="muRecipe">def</span> should-attempt-edit? click-row:num, click-column:num, env:&amp;:environment<span class="muRecipe"> -&gt; </span>result:bool [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   <span class="Comment"># are we below the sandbox editor?</span>
   click-sandbox-area?:bool<span class="Special"> &lt;- </span>click-on-sandbox-area? click-row, click-column, env
   <span class="muControl">reply-unless</span> click-sandbox-area?, <span class="Constant">0/false</span>
   <span class="Comment"># narrower, is the click in the columns spanning the 'edit' button?</span>
-  first-sandbox:&amp;:editor-data<span class="Special"> &lt;- </span>get *env, <span class="Constant">current-sandbox:offset</span>
+  first-sandbox:&amp;:editor<span class="Special"> &lt;- </span>get *env, <span class="Constant">current-sandbox:offset</span>
   assert first-sandbox, <span class="Constant">[!!]</span>
   sandbox-left-margin:num<span class="Special"> &lt;- </span>get *first-sandbox, <span class="Constant">left:offset</span>
   sandbox-right-margin:num<span class="Special"> &lt;- </span>get *first-sandbox, <span class="Constant">right:offset</span>
@@ -185,20 +185,20 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   edit-button-vertical-area?:bool<span class="Special"> &lt;- </span>within-range? click-column, edit-button-left, edit-button-right
   <span class="muControl">reply-unless</span> edit-button-vertical-area?, <span class="Constant">0/false</span>
   <span class="Comment"># finally, is sandbox editor empty?</span>
-  current-sandbox:&amp;:editor-data<span class="Special"> &lt;- </span>get *env, <span class="Constant">current-sandbox:offset</span>
+  current-sandbox:&amp;:editor<span class="Special"> &lt;- </span>get *env, <span class="Constant">current-sandbox:offset</span>
   result<span class="Special"> &lt;- </span>empty-editor? current-sandbox
 ]
 
-<span class="muRecipe">def</span> try-edit-sandbox click-row:num, env:&amp;:programming-environment-data<span class="muRecipe"> -&gt; </span>clicked-on-edit-button?:bool, env:&amp;:programming-environment-data [
+<span class="muRecipe">def</span> try-edit-sandbox click-row:num, env:&amp;:environment<span class="muRecipe"> -&gt; </span>clicked-on-edit-button?:bool, env:&amp;:environment [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   <span class="Comment"># identify the sandbox to edit, if the click was actually on the 'edit' button</span>
-  sandbox:&amp;:sandbox-data<span class="Special"> &lt;- </span>find-sandbox env, click-row
+  sandbox:&amp;:sandbox<span class="Special"> &lt;- </span>find-sandbox env, click-row
   <span class="muControl">return-unless</span> sandbox, <span class="Constant">0/false</span>
   clicked-on-edit-button?<span class="Special"> &lt;- </span>copy <span class="Constant">1/true</span>
   <span class="Comment"># 'edit' button = 'copy' button + 'delete' button</span>
   text:text<span class="Special"> &lt;- </span>get *sandbox, <span class="Constant">data:offset</span>
-  current-sandbox:&amp;:editor-data<span class="Special"> &lt;- </span>get *env, <span class="Constant">current-sandbox:offset</span>
+  current-sandbox:&amp;:editor<span class="Special"> &lt;- </span>get *env, <span class="Constant">current-sandbox:offset</span>
   current-sandbox<span class="Special"> &lt;- </span>insert-text current-sandbox, text
   env<span class="Special"> &lt;- </span>delete-sandbox env, sandbox
   <span class="Comment"># reset scroll</span>
@@ -214,12 +214,12 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[]</span>
   <span class="Comment"># right editor contains an instruction</span>
   <span class="Constant">2</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[print-integer screen, 4]</span>
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
   <span class="Comment"># run the sandbox</span>
   assume-console [
     press F4
   ]
-  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   screen-should-contain [
    <span class="Constant"> .                                                                                 run (F4)           .</span>
    <span class="Constant"> .                                                  ┊                                                 .</span>
@@ -240,7 +240,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     left-click <span class="Constant">3</span>, <span class="Constant">65</span>
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   screen-should-contain [
    <span class="Constant"> .                                                                                 run (F4)           .</span>
@@ -257,8 +257,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Comment"># initialize environment</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[]</span>
   <span class="Constant">2</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[]</span>
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
-  render-all screen, <span class="Constant">3</span>:&amp;:programming-environment-data, render
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  render-all screen, <span class="Constant">3</span>:&amp;:environment, render
   <span class="Comment"># create 2 sandboxes and scroll to second</span>
   assume-console [
     press ctrl-n
@@ -269,7 +269,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press page-down
     press page-down
   ]
-  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   screen-should-contain [
    <span class="Constant"> .                                                                                 run (F4)           .</span>
    <span class="Constant"> .                                                  ┊━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━.</span>
@@ -284,7 +284,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     left-click <span class="Constant">2</span>, <span class="Constant">55</span>
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   <span class="Comment"># second sandbox shows in editor; scroll resets to display first sandbox</span>
   screen-should-contain [
@@ -305,8 +305,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Comment"># initialize environment</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[]</span>
   <span class="Constant">2</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[]</span>
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
-  render-all screen, <span class="Constant">3</span>:&amp;:programming-environment-data, render
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  render-all screen, <span class="Constant">3</span>:&amp;:environment, render
   <span class="Comment"># create 2 sandboxes</span>
   assume-console [
     press ctrl-n
@@ -315,7 +315,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     type <span class="Constant">[add 1, 1]</span>
     press F4
   ]
-  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   screen-should-contain [
    <span class="Constant"> .                                                                                 run (F4)           .</span>
    <span class="Constant"> .                                                  ┊                                                 .</span>
@@ -334,7 +334,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press F4
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   <span class="Comment"># no change in contents</span>
   screen-should-contain [
@@ -356,7 +356,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press page-down
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   <span class="Comment"># screen should show just final sandbox with the right index (1)</span>
   screen-should-contain [
diff --git a/html/edit/009-sandbox-test.mu.html b/html/edit/009-sandbox-test.mu.html
index 1967fa7d..579c4cf2 100644
--- a/html/edit/009-sandbox-test.mu.html
+++ b/html/edit/009-sandbox-test.mu.html
@@ -48,8 +48,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   assume-console [
     press F4
   ]
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
-  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   screen-should-contain [
    <span class="Constant"> .                                                                                 run (F4)           .</span>
    <span class="Constant"> .                                                  ┊                                                 .</span>
@@ -65,7 +65,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     left-click <span class="Constant">5</span>, <span class="Constant">51</span>
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   <span class="Comment"># color toggles to green</span>
   screen-should-contain-in-color <span class="Constant">2/green</span>, [
@@ -104,7 +104,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press F4
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   <span class="Comment"># result turns red</span>
   screen-should-contain-in-color <span class="Constant">1/red</span>, [
@@ -120,7 +120,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 ]
 
 <span class="Comment"># this requires tracking a couple more things</span>
-<span class="muData">container</span> sandbox-data [
+<span class="muData">container</span> sandbox [
   response-starting-row-on-screen:num
   expected-response:text
 ]
@@ -152,14 +152,14 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     click-column:num<span class="Special"> &lt;- </span>get t, <span class="Constant">column:offset</span>
     on-sandbox-side?:bool<span class="Special"> &lt;- </span>greater-or-equal click-column, sandbox-left-margin
     <span class="muControl">break-unless</span> on-sandbox-side?
-    first-sandbox:&amp;:sandbox-data<span class="Special"> &lt;- </span>get *env, <span class="Constant">sandbox:offset</span>
+    first-sandbox:&amp;:sandbox<span class="Special"> &lt;- </span>get *env, <span class="Constant">sandbox:offset</span>
     <span class="muControl">break-unless</span> first-sandbox
     first-sandbox-begins:num<span class="Special"> &lt;- </span>get *first-sandbox, <span class="Constant">starting-row-on-screen:offset</span>
     click-row:num<span class="Special"> &lt;- </span>get t, <span class="Constant">row:offset</span>
     below-sandbox-editor?:bool<span class="Special"> &lt;- </span>greater-or-equal click-row, first-sandbox-begins
     <span class="muControl">break-unless</span> below-sandbox-editor?
     <span class="Comment"># identify the sandbox whose output is being clicked on</span>
-    sandbox:&amp;:sandbox-data<span class="Special"> &lt;- </span>find-click-in-sandbox-output env, click-row
+    sandbox:&amp;:sandbox<span class="Special"> &lt;- </span>find-click-in-sandbox-output env, click-row
     <span class="muControl">break-unless</span> sandbox
     <span class="Comment"># toggle its expected-response, and save session</span>
     sandbox<span class="Special"> &lt;- </span>toggle-expected-response sandbox
@@ -173,17 +173,17 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Delimiter">}</span>
 ]
 
-<span class="muRecipe">def</span> find-click-in-sandbox-output env:&amp;:programming-environment-data, click-row:num<span class="muRecipe"> -&gt; </span>sandbox:&amp;:sandbox-data [
+<span class="muRecipe">def</span> find-click-in-sandbox-output env:&amp;:environment, click-row:num<span class="muRecipe"> -&gt; </span>sandbox:&amp;:sandbox [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   <span class="Comment"># assert click-row &gt;= sandbox.starting-row-on-screen</span>
-  sandbox:&amp;:sandbox-data<span class="Special"> &lt;- </span>get *env, <span class="Constant">sandbox:offset</span>
+  sandbox:&amp;:sandbox<span class="Special"> &lt;- </span>get *env, <span class="Constant">sandbox:offset</span>
   start:num<span class="Special"> &lt;- </span>get *sandbox, <span class="Constant">starting-row-on-screen:offset</span>
   clicked-on-sandboxes?:bool<span class="Special"> &lt;- </span>greater-or-equal click-row, start
   assert clicked-on-sandboxes?, <span class="Constant">[extract-sandbox called on click to sandbox editor]</span>
   <span class="Comment"># while click-row &lt; sandbox.next-sandbox.starting-row-on-screen</span>
   <span class="Delimiter">{</span>
-    next-sandbox:&amp;:sandbox-data<span class="Special"> &lt;- </span>get *sandbox, <span class="Constant">next-sandbox:offset</span>
+    next-sandbox:&amp;:sandbox<span class="Special"> &lt;- </span>get *sandbox, <span class="Constant">next-sandbox:offset</span>
     <span class="muControl">break-unless</span> next-sandbox
     next-start:num<span class="Special"> &lt;- </span>get *next-sandbox, <span class="Constant">starting-row-on-screen:offset</span>
     found?:bool<span class="Special"> &lt;- </span>lesser-than click-row, next-start
@@ -199,7 +199,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="muControl">return</span> sandbox
 ]
 
-<span class="muRecipe">def</span> toggle-expected-response sandbox:&amp;:sandbox-data<span class="muRecipe"> -&gt; </span>sandbox:&amp;:sandbox-data [
+<span class="muRecipe">def</span> toggle-expected-response sandbox:&amp;:sandbox<span class="muRecipe"> -&gt; </span>sandbox:&amp;:sandbox [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   expected-response:text<span class="Special"> &lt;- </span>get *sandbox, <span class="Constant">expected-response:offset</span>
diff --git a/html/edit/010-sandbox-trace.mu.html b/html/edit/010-sandbox-trace.mu.html
index 25c8ff32..5ab47bb0 100644
--- a/html/edit/010-sandbox-trace.mu.html
+++ b/html/edit/010-sandbox-trace.mu.html
@@ -48,8 +48,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   assume-console [
     press F4
   ]
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
-  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   screen-should-contain [
    <span class="Constant"> .                                                                                 run (F4)           .</span>
    <span class="Constant"> .                                                  ┊                                                 .</span>
@@ -64,7 +64,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     left-click <span class="Constant">4</span>, <span class="Constant">51</span>
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
     <span class="Constant">4</span>:char/cursor-icon<span class="Special"> &lt;- </span>copy <span class="Constant">9251/␣</span>
     print screen:&amp;:screen, <span class="Constant">4</span>:char/cursor-icon
   ]
@@ -90,7 +90,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     left-click <span class="Constant">4</span>, <span class="Constant">55</span>
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
     print screen:&amp;:screen, <span class="Constant">4</span>:char/cursor-icon
   ]
   <span class="Comment"># trace hidden again</span>
@@ -119,8 +119,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   assume-console [
     press F4
   ]
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
-  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   screen-should-contain [
    <span class="Constant"> .                                                                                 run (F4)           .</span>
    <span class="Constant"> .                                                  ┊                                                 .</span>
@@ -136,7 +136,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     left-click <span class="Constant">4</span>, <span class="Constant">51</span>
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   <span class="Comment"># trace now printed above result</span>
   screen-should-contain [
@@ -163,8 +163,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press F4
     left-click <span class="Constant">4</span>, <span class="Constant">51</span>
   ]
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
-  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   screen-should-contain [
    <span class="Constant"> .                                                                                 run (F4)           .</span>
    <span class="Constant"> .                                                  ┊                                                 .</span>
@@ -178,7 +178,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     left-click <span class="Constant">5</span>, <span class="Constant">57</span>
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   <span class="Comment"># no change; doesn't die</span>
   screen-should-contain [
@@ -191,13 +191,13 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   ]
 ]
 
-<span class="muData">container</span> sandbox-data [
+<span class="muData">container</span> sandbox [
   trace:text
   display-trace?:bool
 ]
 
 <span class="Comment"># replaced in a later layer</span>
-<span class="muRecipe">def!</span> update-sandbox sandbox:&amp;:sandbox-data, env:&amp;:programming-environment-data, idx:num<span class="muRecipe"> -&gt; </span>sandbox:&amp;:sandbox-data, env:&amp;:programming-environment-data [
+<span class="muRecipe">def!</span> update-sandbox sandbox:&amp;:sandbox, env:&amp;:environment, idx:num<span class="muRecipe"> -&gt; </span>sandbox:&amp;:sandbox, env:&amp;:environment [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   data:text<span class="Special"> &lt;- </span>get *sandbox, <span class="Constant">data:offset</span>
@@ -215,14 +215,14 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     click-column:num<span class="Special"> &lt;- </span>get t, <span class="Constant">column:offset</span>
     on-sandbox-side?:bool<span class="Special"> &lt;- </span>greater-or-equal click-column, sandbox-left-margin
     <span class="muControl">break-unless</span> on-sandbox-side?
-    first-sandbox:&amp;:sandbox-data<span class="Special"> &lt;- </span>get *env, <span class="Constant">sandbox:offset</span>
+    first-sandbox:&amp;:sandbox<span class="Special"> &lt;- </span>get *env, <span class="Constant">sandbox:offset</span>
     <span class="muControl">break-unless</span> first-sandbox
     first-sandbox-begins:num<span class="Special"> &lt;- </span>get *first-sandbox, <span class="Constant">starting-row-on-screen:offset</span>
     click-row:num<span class="Special"> &lt;- </span>get t, <span class="Constant">row:offset</span>
     below-sandbox-editor?:bool<span class="Special"> &lt;- </span>greater-or-equal click-row, first-sandbox-begins
     <span class="muControl">break-unless</span> below-sandbox-editor?
     <span class="Comment"># identify the sandbox whose code is being clicked on</span>
-    sandbox:&amp;:sandbox-data<span class="Special"> &lt;- </span>find-click-in-sandbox-code env, click-row
+    sandbox:&amp;:sandbox<span class="Special"> &lt;- </span>find-click-in-sandbox-code env, click-row
     <span class="muControl">break-unless</span> sandbox
     <span class="Comment"># toggle its display-trace? property</span>
     x:bool<span class="Special"> &lt;- </span>get *sandbox, <span class="Constant">display-trace?:offset</span>
@@ -237,7 +237,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Delimiter">}</span>
 ]
 
-<span class="muRecipe">def</span> find-click-in-sandbox-code env:&amp;:programming-environment-data, click-row:num<span class="muRecipe"> -&gt; </span>sandbox:&amp;:sandbox-data [
+<span class="muRecipe">def</span> find-click-in-sandbox-code env:&amp;:environment, click-row:num<span class="muRecipe"> -&gt; </span>sandbox:&amp;:sandbox [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   <span class="Comment"># assert click-row &gt;= sandbox.starting-row-on-screen</span>
@@ -247,7 +247,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   assert clicked-on-sandboxes?, <span class="Constant">[extract-sandbox called on click to sandbox editor]</span>
   <span class="Comment"># while click-row &lt; sandbox.next-sandbox.starting-row-on-screen</span>
   <span class="Delimiter">{</span>
-    next-sandbox:&amp;:sandbox-data<span class="Special"> &lt;- </span>get *sandbox, <span class="Constant">next-sandbox:offset</span>
+    next-sandbox:&amp;:sandbox<span class="Special"> &lt;- </span>get *sandbox, <span class="Constant">next-sandbox:offset</span>
     <span class="muControl">break-unless</span> next-sandbox
     next-start:num<span class="Special"> &lt;- </span>get *next-sandbox, <span class="Constant">starting-row-on-screen:offset</span>
     found?:bool<span class="Special"> &lt;- </span>lesser-than click-row, next-start
diff --git a/html/edit/011-errors.mu.html b/html/edit/011-errors.mu.html
index 771be1b6..990dd470 100644
--- a/html/edit/011-errors.mu.html
+++ b/html/edit/011-errors.mu.html
@@ -35,15 +35,15 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <pre id='vimCodeElement'>
 <span class="SalientComment">## handling malformed programs</span>
 
-<span class="muData">container</span> programming-environment-data [
+<span class="muData">container</span> environment [
   recipe-errors:text
 ]
 
 <span class="Comment"># copy code from recipe editor, persist, load into mu, save any errors</span>
-<span class="muRecipe">def!</span> update-recipes env:&amp;:programming-environment-data, screen:&amp;:screen<span class="muRecipe"> -&gt; </span>errors-found?:bool, env:&amp;:programming-environment-data, screen:&amp;:screen [
+<span class="muRecipe">def!</span> update-recipes env:&amp;:environment, screen:&amp;:screen<span class="muRecipe"> -&gt; </span>errors-found?:bool, env:&amp;:environment, screen:&amp;:screen [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
-  recipes:&amp;:editor-data<span class="Special"> &lt;- </span>get *env, <span class="Constant">recipes:offset</span>
+  recipes:&amp;:editor<span class="Special"> &lt;- </span>get *env, <span class="Constant">recipes:offset</span>
   in:text<span class="Special"> &lt;- </span>editor-contents recipes
   save <span class="Constant">[recipes.mu]</span>, in
   recipe-errors:text<span class="Special"> &lt;- </span>reload in
@@ -75,7 +75,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Delimiter">}</span>
 ]
 
-<span class="muData">container</span> programming-environment-data [
+<span class="muData">container</span> environment [
   error-index:num  <span class="Comment"># index of first sandbox with an error (or -1 if none)</span>
 ]
 
@@ -108,11 +108,11 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Delimiter">}</span>
 ]
 
-<span class="muData">container</span> sandbox-data [
+<span class="muData">container</span> sandbox [
   errors:text
 ]
 
-<span class="muRecipe">def!</span> update-sandbox sandbox:&amp;:sandbox-data, env:&amp;:programming-environment-data, idx:num<span class="muRecipe"> -&gt; </span>sandbox:&amp;:sandbox-data, env:&amp;:programming-environment-data [
+<span class="muRecipe">def!</span> update-sandbox sandbox:&amp;:sandbox, env:&amp;:environment, idx:num<span class="muRecipe"> -&gt; </span>sandbox:&amp;:sandbox, env:&amp;:environment [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   data:text<span class="Special"> &lt;- </span>get *sandbox, <span class="Constant">data:offset</span>
@@ -157,12 +157,12 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="Constant">  get 123:num, foo:offset</span>
 <span class="Constant">]</span>]
   <span class="Constant">2</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[foo]</span>
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
   assume-console [
     press F4
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   screen-should-contain [
    <span class="Constant"> .  errors found                                                                   run (F4)           .</span>
@@ -194,7 +194,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   assume-screen <span class="Constant">100/width</span>, <span class="Constant">15/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[]</span>
   <span class="Constant">2</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[]</span>
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
   assume-console [
     left-click <span class="Constant">3</span>, <span class="Constant">80</span>
     <span class="Comment"># create invalid sandbox 1</span>
@@ -205,7 +205,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press F4
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   <span class="Comment"># status line shows that error is in first sandbox</span>
   screen-should-contain [
@@ -218,7 +218,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   assume-screen <span class="Constant">100/width</span>, <span class="Constant">15/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[]</span>
   <span class="Constant">2</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[]</span>
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
   assume-console [
     left-click <span class="Constant">3</span>, <span class="Constant">80</span>
     <span class="Comment"># create invalid sandbox 2</span>
@@ -232,7 +232,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press F4
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   <span class="Comment"># status line shows that error is in second sandbox</span>
   screen-should-contain [
@@ -245,12 +245,12 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   assume-screen <span class="Constant">100/width</span>, <span class="Constant">15/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[]</span>
   <span class="Constant">2</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[get foo, x:offset]</span>  <span class="Comment"># invalid</span>
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
   assume-console [
     press F4  <span class="Comment"># generate error</span>
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   assume-console [
     left-click <span class="Constant">3</span>, <span class="Constant">58</span>
@@ -259,7 +259,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press F4  <span class="Comment"># update sandbox</span>
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   <span class="Comment"># error should disappear</span>
   screen-should-contain [
@@ -285,11 +285,11 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="Constant">z &lt;- add x, y</span>
 <span class="Constant">]</span>]
   <span class="Constant">2</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[foo 2]</span>
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
   assume-console [
     press F4
   ]
-  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   screen-should-contain [
    <span class="Constant"> .  errors found (0)                                                               run (F4)           .</span>
    <span class="Constant"> .recipe foo x:_elem -&gt; z:_elem [                   ┊                                                 .</span>
@@ -306,7 +306,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press F4
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   <span class="Comment"># error should remain unchanged</span>
   screen-should-contain [
@@ -331,12 +331,12 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Comment"># call code that uses other variants of it, but not it itself</span>
   <span class="Constant">2</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[x:&amp;:list:num &lt;- copy 0</span>
 <span class="Constant">to-text x]</span>
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
   <span class="Comment"># run it once</span>
   assume-console [
     press F4
   ]
-  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   <span class="Comment"># no errors anywhere on screen (can't check anything else, since to-text will return an address)</span>
   screen-should-contain-in-color <span class="Constant">1/red</span>, [
    <span class="Constant"> .                                                                                                    .</span>
@@ -360,7 +360,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press F4
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   <span class="Comment"># still no errors</span>
   screen-should-contain-in-color <span class="Constant">1/red</span>, [
@@ -390,12 +390,12 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="Constant">  x &lt;- copy 0</span>
 <span class="Constant">]</span>]
   <span class="Constant">2</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[foo]</span>
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
   assume-console [
     press F4
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   screen-should-contain [
    <span class="Constant"> .  errors found                                                                   run (F4)           .</span>
@@ -416,12 +416,12 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="Constant">  x &lt;- copy 0</span>
 <span class="Constant">]</span>
   <span class="Constant">2</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[foo]</span>
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
   assume-console [
     press F4
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   screen-should-contain [
    <span class="Constant"> .  errors found                                                                   run (F4)           .</span>
@@ -445,12 +445,12 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="Constant">  get x:&amp;:point, 1:offset</span>
 <span class="Constant">]</span>]
   <span class="Constant">2</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[foo]</span>
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
   assume-console [
     press F4
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   screen-should-contain [
    <span class="Constant"> .  errors found                                                                   run (F4)           .</span>
@@ -478,12 +478,12 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="Constant">  get *y:&amp;:point, x:num</span>
 <span class="Constant">]</span>]
   <span class="Constant">2</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[foo]</span>
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
   assume-console [
     press F4
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   screen-should-contain [
    <span class="Constant"> .  errors found                                                                   run (F4)           .</span>
@@ -511,11 +511,11 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="Constant">  x:num &lt;- copy y:num</span>
 <span class="Constant">]</span>]
   <span class="Constant">2</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[foo]</span>
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
   assume-console [
     press F4
   ]
-  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   screen-should-contain [
    <span class="Constant"> .  errors found                                                                   run (F4)           .</span>
    <span class="Constant"> .                                                  ┊foo                                              .</span>
@@ -532,7 +532,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press F4
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   screen-should-contain [
    <span class="Constant"> .  errors found                                                                   run (F4)           .</span>
@@ -554,13 +554,13 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[]</span>
   <span class="Comment"># right editor contains an illegal instruction</span>
   <span class="Constant">2</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[get 1234:num, foo:offset]</span>
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
   <span class="Comment"># run the code in the editors</span>
   assume-console [
     press F4
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   <span class="Comment"># check that screen prints error message in red</span>
   screen-should-contain [
@@ -617,14 +617,14 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[]</span>
   <span class="Comment"># right editor contains an illegal instruction</span>
   <span class="Constant">2</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[get 1234:num, foo:offset]</span>
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
   <span class="Comment"># run the code in the editors multiple times</span>
   assume-console [
     press F4
     press F4
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   <span class="Comment"># check that screen prints error message just once</span>
   screen-should-contain [
@@ -652,13 +652,13 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="Constant">]</span>]
   <span class="Comment"># right editor contains an instruction</span>
   <span class="Constant">2</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[foo]</span>
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
   <span class="Comment"># run the sandbox</span>
   assume-console [
     press F4
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   screen-should-contain [
    <span class="Constant"> .  errors found (0)                                                               run (F4)           .</span>
@@ -685,12 +685,12 @@ _, c:num<span class="Special"> &lt;- </span>divide-with-remainder a, b
 <span class="muControl">reply</span> b
 ]]
   <span class="Constant">2</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[foo 4, 0]</span>
-  <span class="Constant">3</span>:&amp;:programming-environment-data<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
+  <span class="Constant">3</span>:&amp;:environment<span class="Special"> &lt;- </span>new-programming-environment screen:&amp;:screen, <span class="Constant">1</span>:text, <span class="Constant">2</span>:text
   <span class="Comment"># run</span>
   assume-console [
     press F4
   ]
-  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+  event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   <span class="Comment"># screen prints error message</span>
   screen-should-contain [
    <span class="Constant"> .  errors found (0)                                                               run (F4)           .</span>
@@ -708,7 +708,7 @@ _, c:num<span class="Special"> &lt;- </span>divide-with-remainder a, b
     left-click <span class="Constant">4</span>, <span class="Constant">55</span>
   ]
   run [
-    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:programming-environment-data
+    event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">3</span>:&amp;:environment
   ]
   <span class="Comment"># screen should expand trace</span>
   screen-should-contain [
diff --git a/html/edit/012-editor-undo.mu.html b/html/edit/012-editor-undo.mu.html
index 0233a08a..45abb7e9 100644
--- a/html/edit/012-editor-undo.mu.html
+++ b/html/edit/012-editor-undo.mu.html
@@ -90,7 +90,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 ]
 
 <span class="Comment"># every editor accumulates a list of operations to undo/redo</span>
-<span class="muData">container</span> editor-data [
+<span class="muData">container</span> editor [
   undo:&amp;:list:&amp;:operation
   redo:&amp;:list:&amp;:operation
 ]
@@ -137,18 +137,18 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Comment"># create an editor and type a character</span>
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
   assume-console [
     type <span class="Constant">[0]</span>
   ]
-  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   <span class="Comment"># undo</span>
   assume-console [
     press ctrl-z
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># character should be gone</span>
   screen-should-contain [
@@ -162,7 +162,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     type <span class="Constant">[1]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -232,7 +232,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="Comment"># redo stack, because it's now obsolete.</span>
 <span class="Comment"># Beware: since we're counting cursor moves as operations, this means just</span>
 <span class="Comment"># moving the cursor can lose work on the undo stack.</span>
-<span class="muRecipe">def</span> add-operation editor:&amp;:editor-data, op:&amp;:operation<span class="muRecipe"> -&gt; </span>editor:&amp;:editor-data [
+<span class="muRecipe">def</span> add-operation editor:&amp;:editor, op:&amp;:operation<span class="muRecipe"> -&gt; </span>editor:&amp;:editor [
   <span class="Constant">local-scope</span>
   <span class="Constant">load-ingredients</span>
   undo:&amp;:list:&amp;:operation<span class="Special"> &lt;- </span>get *editor, <span class="Constant">undo:offset</span>
@@ -267,18 +267,18 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Comment"># create an editor and type multiple characters</span>
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
   assume-console [
     type <span class="Constant">[012]</span>
   ]
-  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   <span class="Comment"># undo</span>
   assume-console [
     press ctrl-z
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># all characters must be gone</span>
   screen-should-contain [
@@ -293,13 +293,13 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Comment"># create an editor with some text</span>
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[a]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
   <span class="Comment"># type some characters</span>
   assume-console [
     type <span class="Constant">[012]</span>
   ]
-  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   screen-should-contain [
    <span class="Constant"> .          .</span>
    <span class="Constant"> .012a      .</span>
@@ -311,7 +311,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press ctrl-z
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># back to original text</span>
   screen-should-contain [
@@ -325,7 +325,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     type <span class="Constant">[3]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -339,14 +339,14 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Comment"># create an editor with some text</span>
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[  abc]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
   <span class="Comment"># new line</span>
   assume-console [
     left-click <span class="Constant">1</span>, <span class="Constant">8</span>
     press enter
   ]
-  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   screen-should-contain [
    <span class="Constant"> .          .</span>
    <span class="Constant"> .  abc     .</span>
@@ -355,8 +355,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
    <span class="Constant"> .          .</span>
   ]
   <span class="Comment"># line is indented</span>
-  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   memory-should-contain [
     <span class="Constant">3</span><span class="Special"> &lt;- </span><span class="Constant">2</span>
     <span class="Constant">4</span><span class="Special"> &lt;- </span><span class="Constant">2</span>
@@ -366,10 +366,10 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press ctrl-z
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
-  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   memory-should-contain [
     <span class="Constant">3</span><span class="Special"> &lt;- </span><span class="Constant">1</span>
     <span class="Constant">4</span><span class="Special"> &lt;- </span><span class="Constant">5</span>
@@ -386,7 +386,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     type <span class="Constant">[1]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -402,13 +402,13 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Comment"># create an editor, type something, undo</span>
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[a]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
   assume-console [
     type <span class="Constant">[012]</span>
     press ctrl-z
   ]
-  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   screen-should-contain [
    <span class="Constant"> .          .</span>
    <span class="Constant"> .a         .</span>
@@ -420,7 +420,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press ctrl-y
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># all characters must be back</span>
   screen-should-contain [
@@ -434,7 +434,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     type <span class="Constant">[3]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -466,13 +466,13 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Comment"># create an editor, type something, undo</span>
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
   assume-console [
     type <span class="Constant">[012]</span>
     press ctrl-z
   ]
-  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   screen-should-contain [
    <span class="Constant"> .          .</span>
    <span class="Constant"> .          .</span>
@@ -484,7 +484,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press ctrl-y
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># all characters must be back</span>
   screen-should-contain [
@@ -498,7 +498,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     type <span class="Constant">[3]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -514,18 +514,18 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc</span>
 <span class="Constant">def</span>
 <span class="Constant">ghi]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
   assume-console [
     type <span class="Constant">[1]</span>
     press ctrl-z
   ]
-  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   <span class="Comment"># do some more work</span>
   assume-console [
     type <span class="Constant">[0]</span>
   ]
-  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   screen-should-contain [
    <span class="Constant"> .          .</span>
    <span class="Constant"> .0abc      .</span>
@@ -538,7 +538,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press ctrl-y
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># nothing should happen</span>
   screen-should-contain [
@@ -554,8 +554,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Comment"># create an editor</span>
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
   <span class="Comment"># insert some text and tabs, hit enter, some more text and tabs</span>
   assume-console [
     press tab
@@ -566,7 +566,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press tab
     type <span class="Constant">[efg]</span>
   ]
-  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   screen-should-contain [
    <span class="Constant"> .          .</span>
    <span class="Constant"> .  ab  cd  .</span>
@@ -574,8 +574,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="Constant">    .┈┈┈┈┈┈┈┈┈┈.</span>
    <span class="Constant"> .          .</span>
   ]
-  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   memory-should-contain [
     <span class="Constant">3</span><span class="Special"> &lt;- </span><span class="Constant">2</span>
     <span class="Constant">4</span><span class="Special"> &lt;- </span><span class="Constant">7</span>
@@ -585,11 +585,11 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press ctrl-z
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># typing in second line deleted, but not indent</span>
-  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   memory-should-contain [
     <span class="Constant">3</span><span class="Special"> &lt;- </span><span class="Constant">2</span>
     <span class="Constant">4</span><span class="Special"> &lt;- </span><span class="Constant">2</span>
@@ -606,11 +606,11 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press ctrl-z
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># indent and newline deleted</span>
-  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   memory-should-contain [
     <span class="Constant">3</span><span class="Special"> &lt;- </span><span class="Constant">1</span>
     <span class="Constant">4</span><span class="Special"> &lt;- </span><span class="Constant">8</span>
@@ -626,11 +626,11 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press ctrl-z
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># empty screen</span>
-  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   memory-should-contain [
     <span class="Constant">3</span><span class="Special"> &lt;- </span><span class="Constant">1</span>
     <span class="Constant">4</span><span class="Special"> &lt;- </span><span class="Constant">0</span>
@@ -646,11 +646,11 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press ctrl-y
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># first line inserted</span>
-  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   memory-should-contain [
     <span class="Constant">3</span><span class="Special"> &lt;- </span><span class="Constant">1</span>
     <span class="Constant">4</span><span class="Special"> &lt;- </span><span class="Constant">8</span>
@@ -666,11 +666,11 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press ctrl-y
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># newline and indent inserted</span>
-  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   memory-should-contain [
     <span class="Constant">3</span><span class="Special"> &lt;- </span><span class="Constant">2</span>
     <span class="Constant">4</span><span class="Special"> &lt;- </span><span class="Constant">2</span>
@@ -687,11 +687,11 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press ctrl-y
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># indent and newline deleted</span>
-  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   memory-should-contain [
     <span class="Constant">3</span><span class="Special"> &lt;- </span><span class="Constant">2</span>
     <span class="Constant">4</span><span class="Special"> &lt;- </span><span class="Constant">7</span>
@@ -713,21 +713,21 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc</span>
 <span class="Constant">def</span>
 <span class="Constant">ghi]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
   <span class="Comment"># move the cursor</span>
   assume-console [
     left-click <span class="Constant">3</span>, <span class="Constant">1</span>
   ]
-  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   <span class="Comment"># undo</span>
   assume-console [
     press ctrl-z
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   <span class="Comment"># click undone</span>
   memory-should-contain [
@@ -739,7 +739,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     type <span class="Constant">[1]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -804,15 +804,15 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[a</span>
 <span class="Constant">b</span>
 <span class="Constant">cdefgh]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
   <span class="Comment"># position cursor at end of screen and try to move right</span>
   assume-console [
     left-click <span class="Constant">3</span>, <span class="Constant">3</span>
     press right-arrow
   ]
-  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   <span class="Comment"># screen scrolls</span>
   screen-should-contain [
    <span class="Constant"> .     .</span>
@@ -829,9 +829,9 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press ctrl-z
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   <span class="Comment"># cursor moved back</span>
   memory-should-contain [
@@ -850,7 +850,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     type <span class="Constant">[1]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .     .</span>
@@ -866,22 +866,22 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc</span>
 <span class="Constant">def</span>
 <span class="Constant">ghi]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
   <span class="Comment"># move the cursor</span>
   assume-console [
     left-click <span class="Constant">3</span>, <span class="Constant">1</span>
     press left-arrow
   ]
-  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   <span class="Comment"># undo</span>
   assume-console [
     press ctrl-z
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   <span class="Comment"># cursor moves back</span>
   memory-should-contain [
@@ -893,7 +893,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     type <span class="Constant">[1]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -910,16 +910,16 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc</span>
 <span class="Constant">def</span>
 <span class="Constant">ghi]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
   <span class="Comment"># move the cursor</span>
   assume-console [
     left-click <span class="Constant">3</span>, <span class="Constant">1</span>
     press up-arrow
   ]
-  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   memory-should-contain [
     <span class="Constant">3</span><span class="Special"> &lt;- </span><span class="Constant">2</span>
     <span class="Constant">4</span><span class="Special"> &lt;- </span><span class="Constant">1</span>
@@ -929,9 +929,9 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press ctrl-z
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   <span class="Comment"># cursor moves back</span>
   memory-should-contain [
@@ -943,7 +943,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     type <span class="Constant">[1]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -960,22 +960,22 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc</span>
 <span class="Constant">def</span>
 <span class="Constant">ghi]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
   <span class="Comment"># move the cursor</span>
   assume-console [
     left-click <span class="Constant">2</span>, <span class="Constant">1</span>
     press down-arrow
   ]
-  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   <span class="Comment"># undo</span>
   assume-console [
     press ctrl-z
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   <span class="Comment"># cursor moves back</span>
   memory-should-contain [
@@ -987,7 +987,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     type <span class="Constant">[1]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -1007,21 +1007,21 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="Constant">d</span>
 <span class="Constant">e</span>
 <span class="Constant">f]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
   <span class="Comment"># scroll the page</span>
   assume-console [
     press ctrl-f
   ]
-  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   <span class="Comment"># undo</span>
   assume-console [
     press ctrl-z
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   <span class="Comment"># screen should again show page 1</span>
   screen-should-contain [
@@ -1042,21 +1042,21 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="Constant">d</span>
 <span class="Constant">e</span>
 <span class="Constant">f]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
   <span class="Comment"># scroll the page</span>
   assume-console [
     press page-down
   ]
-  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   <span class="Comment"># undo</span>
   assume-console [
     press ctrl-z
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   <span class="Comment"># screen should again show page 1</span>
   screen-should-contain [
@@ -1077,22 +1077,22 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="Constant">d</span>
 <span class="Constant">e</span>
 <span class="Constant">f]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
   <span class="Comment"># scroll the page down and up</span>
   assume-console [
     press page-down
     press ctrl-b
   ]
-  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   <span class="Comment"># undo</span>
   assume-console [
     press ctrl-z
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   <span class="Comment"># screen should again show page 2</span>
   screen-should-contain [
@@ -1113,22 +1113,22 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="Constant">d</span>
 <span class="Constant">e</span>
 <span class="Constant">f]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
   <span class="Comment"># scroll the page down and up</span>
   assume-console [
     press page-down
     press page-up
   ]
-  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   <span class="Comment"># undo</span>
   assume-console [
     press ctrl-z
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   <span class="Comment"># screen should again show page 2</span>
   screen-should-contain [
@@ -1146,22 +1146,22 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc</span>
 <span class="Constant">def</span>
 <span class="Constant">ghi]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
   <span class="Comment"># move the cursor, then to start of line</span>
   assume-console [
     left-click <span class="Constant">2</span>, <span class="Constant">1</span>
     press ctrl-a
   ]
-  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   <span class="Comment"># undo</span>
   assume-console [
     press ctrl-z
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   <span class="Comment"># cursor moves back</span>
   memory-should-contain [
@@ -1173,7 +1173,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     type <span class="Constant">[1]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -1190,22 +1190,22 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc</span>
 <span class="Constant">def</span>
 <span class="Constant">ghi]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
   <span class="Comment"># move the cursor, then to start of line</span>
   assume-console [
     left-click <span class="Constant">2</span>, <span class="Constant">1</span>
     press home
   ]
-  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   <span class="Comment"># undo</span>
   assume-console [
     press ctrl-z
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   <span class="Comment"># cursor moves back</span>
   memory-should-contain [
@@ -1217,7 +1217,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     type <span class="Constant">[1]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -1234,22 +1234,22 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc</span>
 <span class="Constant">def</span>
 <span class="Constant">ghi]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
   <span class="Comment"># move the cursor, then to start of line</span>
   assume-console [
     left-click <span class="Constant">2</span>, <span class="Constant">1</span>
     press ctrl-e
   ]
-  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   <span class="Comment"># undo</span>
   assume-console [
     press ctrl-z
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   <span class="Comment"># cursor moves back</span>
   memory-should-contain [
@@ -1261,7 +1261,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     type <span class="Constant">[1]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -1278,22 +1278,22 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc</span>
 <span class="Constant">def</span>
 <span class="Constant">ghi]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
   <span class="Comment"># move the cursor, then to start of line</span>
   assume-console [
     left-click <span class="Constant">2</span>, <span class="Constant">1</span>
     press end
   ]
-  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   <span class="Comment"># undo</span>
   assume-console [
     press ctrl-z
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   <span class="Comment"># cursor moves back</span>
   memory-should-contain [
@@ -1305,7 +1305,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     type <span class="Constant">[1]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -1322,8 +1322,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc</span>
 <span class="Constant">def</span>
 <span class="Constant">ghi]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
   <span class="Comment"># move the cursor</span>
   assume-console [
     left-click <span class="Constant">2</span>, <span class="Constant">1</span>
@@ -1331,9 +1331,9 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press right-arrow
     press up-arrow
   ]
-  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   memory-should-contain [
     <span class="Constant">3</span><span class="Special"> &lt;- </span><span class="Constant">1</span>
     <span class="Constant">4</span><span class="Special"> &lt;- </span><span class="Constant">3</span>
@@ -1343,9 +1343,9 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press ctrl-z
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   <span class="Comment"># up-arrow is undone</span>
   memory-should-contain [
@@ -1357,9 +1357,9 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press ctrl-z
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   <span class="Comment"># both right-arrows are undone</span>
   memory-should-contain [
@@ -1376,21 +1376,21 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc</span>
 <span class="Constant">def</span>
 <span class="Constant">ghi]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
   assume-console [
     left-click <span class="Constant">3</span>, <span class="Constant">1</span>
     press ctrl-z
   ]
-  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   <span class="Comment"># redo</span>
   assume-console [
     press ctrl-y
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   <span class="Comment"># cursor moves to left-click</span>
   memory-should-contain [
@@ -1402,7 +1402,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     type <span class="Constant">[1]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -1431,16 +1431,16 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Comment"># create an editor, type some text, move the cursor, type some more text</span>
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
   assume-console [
     type <span class="Constant">[abc]</span>
     left-click <span class="Constant">1</span>, <span class="Constant">1</span>
     type <span class="Constant">[d]</span>
   ]
-  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   screen-should-contain [
    <span class="Constant"> .          .</span>
    <span class="Constant"> .adbc      .</span>
@@ -1456,9 +1456,9 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press ctrl-z
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   <span class="Comment"># last letter typed is deleted</span>
   screen-should-contain [
@@ -1476,9 +1476,9 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press ctrl-z
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   <span class="Comment"># no change to screen; cursor moves</span>
   screen-should-contain [
@@ -1496,9 +1496,9 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press ctrl-z
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   <span class="Comment"># screen empty</span>
   screen-should-contain [
@@ -1516,9 +1516,9 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press ctrl-y
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   <span class="Comment"># first insert</span>
   screen-should-contain [
@@ -1536,9 +1536,9 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press ctrl-y
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   <span class="Comment"># cursor moves</span>
   screen-should-contain [
@@ -1557,9 +1557,9 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press ctrl-y
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
-    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
+    <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+    <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   ]
   <span class="Comment"># second insert</span>
   screen-should-contain [
@@ -1580,23 +1580,23 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Comment"># create an editor</span>
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
   <span class="Comment"># insert some text and hit backspace</span>
   assume-console [
     type <span class="Constant">[abc]</span>
     press backspace
     press backspace
   ]
-  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   screen-should-contain [
    <span class="Constant"> .          .</span>
    <span class="Constant"> .a         .</span>
 <span class="Constant">    .┈┈┈┈┈┈┈┈┈┈.</span>
    <span class="Constant"> .          .</span>
   ]
-  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   memory-should-contain [
     <span class="Constant">3</span><span class="Special"> &lt;- </span><span class="Constant">1</span>
     <span class="Constant">4</span><span class="Special"> &lt;- </span><span class="Constant">1</span>
@@ -1606,10 +1606,10 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press ctrl-z
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
-  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   memory-should-contain [
     <span class="Constant">3</span><span class="Special"> &lt;- </span><span class="Constant">1</span>
     <span class="Constant">4</span><span class="Special"> &lt;- </span><span class="Constant">3</span>
@@ -1625,10 +1625,10 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press ctrl-y
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
-  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   memory-should-contain [
     <span class="Constant">3</span><span class="Special"> &lt;- </span><span class="Constant">1</span>
     <span class="Constant">4</span><span class="Special"> &lt;- </span><span class="Constant">1</span>
@@ -1725,8 +1725,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Comment"># create an editor</span>
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
   <span class="Comment"># insert some text and hit delete and backspace a few times</span>
   assume-console [
     type <span class="Constant">[abcdef]</span>
@@ -1736,15 +1736,15 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press delete
     press delete
   ]
-  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   screen-should-contain [
    <span class="Constant"> .          .</span>
    <span class="Constant"> .af        .</span>
 <span class="Constant">    .┈┈┈┈┈┈┈┈┈┈.</span>
    <span class="Constant"> .          .</span>
   ]
-  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   memory-should-contain [
     <span class="Constant">3</span><span class="Special"> &lt;- </span><span class="Constant">1</span>
     <span class="Constant">4</span><span class="Special"> &lt;- </span><span class="Constant">1</span>
@@ -1754,10 +1754,10 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press ctrl-z
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
-  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   memory-should-contain [
     <span class="Constant">3</span><span class="Special"> &lt;- </span><span class="Constant">1</span>
     <span class="Constant">4</span><span class="Special"> &lt;- </span><span class="Constant">1</span>
@@ -1773,10 +1773,10 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press ctrl-z
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
-  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   memory-should-contain [
     <span class="Constant">3</span><span class="Special"> &lt;- </span><span class="Constant">1</span>
     <span class="Constant">4</span><span class="Special"> &lt;- </span><span class="Constant">2</span>
@@ -1792,10 +1792,10 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press ctrl-z
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
-  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   memory-should-contain [
     <span class="Constant">3</span><span class="Special"> &lt;- </span><span class="Constant">1</span>
     <span class="Constant">4</span><span class="Special"> &lt;- </span><span class="Constant">2</span>
@@ -1811,11 +1811,11 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press ctrl-y
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># first line inserted</span>
-  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   memory-should-contain [
     <span class="Constant">3</span><span class="Special"> &lt;- </span><span class="Constant">1</span>
     <span class="Constant">4</span><span class="Special"> &lt;- </span><span class="Constant">2</span>
@@ -1831,11 +1831,11 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press ctrl-y
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># first line inserted</span>
-  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   memory-should-contain [
     <span class="Constant">3</span><span class="Special"> &lt;- </span><span class="Constant">1</span>
     <span class="Constant">4</span><span class="Special"> &lt;- </span><span class="Constant">1</span>
@@ -1851,11 +1851,11 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press ctrl-y
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># first line inserted</span>
-  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   memory-should-contain [
     <span class="Constant">3</span><span class="Special"> &lt;- </span><span class="Constant">1</span>
     <span class="Constant">4</span><span class="Special"> &lt;- </span><span class="Constant">1</span>
@@ -1915,14 +1915,14 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc</span>
 <span class="Constant">def]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
   <span class="Comment"># insert some text and hit delete and backspace a few times</span>
   assume-console [
     left-click <span class="Constant">1</span>, <span class="Constant">1</span>
     press ctrl-k
   ]
-  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   screen-should-contain [
    <span class="Constant"> .          .</span>
    <span class="Constant"> .a         .</span>
@@ -1930,8 +1930,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="Constant">    .┈┈┈┈┈┈┈┈┈┈.</span>
    <span class="Constant"> .          .</span>
   ]
-  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   memory-should-contain [
     <span class="Constant">3</span><span class="Special"> &lt;- </span><span class="Constant">1</span>
     <span class="Constant">4</span><span class="Special"> &lt;- </span><span class="Constant">1</span>
@@ -1941,7 +1941,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press ctrl-z
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -1950,8 +1950,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="Constant">    .┈┈┈┈┈┈┈┈┈┈.</span>
    <span class="Constant"> .          .</span>
   ]
-  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   memory-should-contain [
     <span class="Constant">3</span><span class="Special"> &lt;- </span><span class="Constant">1</span>
     <span class="Constant">4</span><span class="Special"> &lt;- </span><span class="Constant">1</span>
@@ -1961,7 +1961,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press ctrl-y
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># first line inserted</span>
   screen-should-contain [
@@ -1971,8 +1971,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="Constant">    .┈┈┈┈┈┈┈┈┈┈.</span>
    <span class="Constant"> .          .</span>
   ]
-  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   memory-should-contain [
     <span class="Constant">3</span><span class="Special"> &lt;- </span><span class="Constant">1</span>
     <span class="Constant">4</span><span class="Special"> &lt;- </span><span class="Constant">1</span>
@@ -1982,7 +1982,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     type <span class="Constant">[1]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -2017,14 +2017,14 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[abc</span>
 <span class="Constant">def]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
   <span class="Comment"># insert some text and hit delete and backspace a few times</span>
   assume-console [
     left-click <span class="Constant">1</span>, <span class="Constant">2</span>
     press ctrl-u
   ]
-  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   screen-should-contain [
    <span class="Constant"> .          .</span>
    <span class="Constant"> .c         .</span>
@@ -2032,8 +2032,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="Constant">    .┈┈┈┈┈┈┈┈┈┈.</span>
    <span class="Constant"> .          .</span>
   ]
-  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   memory-should-contain [
     <span class="Constant">3</span><span class="Special"> &lt;- </span><span class="Constant">1</span>
     <span class="Constant">4</span><span class="Special"> &lt;- </span><span class="Constant">0</span>
@@ -2043,7 +2043,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press ctrl-z
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -2052,8 +2052,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="Constant">    .┈┈┈┈┈┈┈┈┈┈.</span>
    <span class="Constant"> .          .</span>
   ]
-  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   memory-should-contain [
     <span class="Constant">3</span><span class="Special"> &lt;- </span><span class="Constant">1</span>
     <span class="Constant">4</span><span class="Special"> &lt;- </span><span class="Constant">2</span>
@@ -2063,7 +2063,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     press ctrl-y
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   <span class="Comment"># first line inserted</span>
   screen-should-contain [
@@ -2073,8 +2073,8 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
 <span class="Constant">    .┈┈┈┈┈┈┈┈┈┈.</span>
    <span class="Constant"> .          .</span>
   ]
-  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-row:offset</span>
-  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor-data, <span class="Constant">cursor-column:offset</span>
+  <span class="Constant">3</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-row:offset</span>
+  <span class="Constant">4</span>:num<span class="Special"> &lt;- </span>get *<span class="Constant">2</span>:&amp;:editor, <span class="Constant">cursor-column:offset</span>
   memory-should-contain [
     <span class="Constant">3</span><span class="Special"> &lt;- </span><span class="Constant">1</span>
     <span class="Constant">4</span><span class="Special"> &lt;- </span><span class="Constant">0</span>
@@ -2084,7 +2084,7 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
     type <span class="Constant">[1]</span>
   ]
   run [
-    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+    editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   ]
   screen-should-contain [
    <span class="Constant"> .          .</span>
@@ -2117,15 +2117,15 @@ body { font-size: 12pt; font-family: monospace; color: #eeeeee; background-color
   <span class="Comment"># create an editor</span>
   assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
   <span class="Constant">1</span>:text<span class="Special"> &lt;- </span>new <span class="Constant">[]</span>
-  <span class="Constant">2</span>:&amp;:editor-data<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
-  editor-render screen, <span class="Constant">2</span>:&amp;:editor-data
+  <span class="Constant">2</span>:&amp;:editor<span class="Special"> &lt;- </span>new-editor <span class="Constant">1</span>:text, screen:&amp;:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
+  editor-render screen, <span class="Constant">2</span>:&amp;:editor
   <span class="Comment"># insert some text and hit delete and backspace a few times</span>
   assume-console [
     type <span class="Constant">[abc]</span>
     press ctrl-u
     press ctrl-z
   ]
-  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor-data
+  editor-event-loop screen:&amp;:screen, console:&amp;:console, <span class="Constant">2</span>:&amp;:editor
   screen-should-contain [
    <span class="Constant"> .          .</span>
    <span class="Constant"> .abc       .</span>