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<span class="SalientComment">## the basic editor data structure, and how it displays text to the screen</span>
<span class="Comment"># temporary main for this layer: just render the given text at the given</span>
<span class="Comment"># screen dimensions, then stop</span>
<span class="muRecipe">def!</span> main text:text [
<span class="Constant">local-scope</span>
<span class="Constant">load-ingredients</span>
open-console
hide-screen <span class="Constant">0/screen</span>
new-editor text, <span class="Constant">0/screen</span>, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
show-screen <span class="Constant">0/screen</span>
wait-for-event <span class="Constant">0/console</span>
close-console
]
<span class="muScenario">scenario</span> editor-initially-prints-text-to-screen [
assume-screen <span class="Constant">10/width</span>, <span class="Constant">5/height</span>
run [
<span class="Constant">1</span>:text<span class="Special"> <- </span>new <span class="Constant">[abc]</span>
new-editor <span class="Constant">1</span>:text, screen:&:screen, <span class="Constant">0/left</span>, <span class="Constant">10/right</span>
]
screen-should-contain [
<span class="Comment"># top line of screen reserved for menu</span>
<span class="Constant"> . .</span>
<span class="Constant"> .abc .</span>
<span class="Constant"> . .</span>
]
]
<span class="muData">container</span> editor [
<span class="Comment"># editable text: doubly linked list of characters (head contains a special sentinel)</span>
data:&:duplex-list:char
top-of-screen:&:duplex-list:char
bottom-of-screen:&:duplex-list:char
<span class="Comment"># location before cursor inside data</span>
before-cursor:&:duplex-list:char
<span class="Comment"># raw bounds of display area on screen</span>
<span class="Comment"># always displays from row 1 (leaving row 0 for a menu) and at most until bottom of screen</span>
left:num
right:num
bottom:num
<span class="Comment"># raw screen coordinates of cursor</span>
cursor-row:num
cursor-column:num
]
<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:&:screen, left:num, right:num<span class="muRecipe"> -> </span>result:&:editor, screen:&: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"> <- </span>subtract right, <span class="Constant">1</span>
result<span class="Special"> <- </span>new <span class="Constant">editor:type</span>
<span class="Comment"># initialize screen-related fields</span>
*result<span class="Special"> <- </span>put *result, <span class="Constant">left:offset</span>, left
*result<span class="Special"> <- </span>put *result, <span class="Constant">right:offset</span>, right
<span class="Comment"># initialize cursor coordinates</span>
*result<span class="Special"> <- </span>put *result, <span class="Constant">cursor-row:offset</span>, <span class="Constant">1/top</span>
*result<span class="Special"> <- </span>put *result, <span class="Constant">cursor-column:offset</span>, left
<span class="Comment"># initialize empty contents</span>
init:&:duplex-list:char<span class="Special"> <- </span>push <span class="Constant">167/§</span>, <span class="Constant">0/tail</span>
*result<span class="Special"> <- </span>put *result, <span class="Constant">data:offset</span>, init
*result<span class="Special"> <- </span>put *result, <span class="Constant">top-of-screen:offset</span>, init
*result<span class="Special"> <- </span>put *result, <span class="Constant">before-cursor:offset</span>, init
result<span class="Special"> <- </span>insert-text result, s
<span class="Comment"># initial render to screen, just for some old tests</span>
_, _, screen, result<span class="Special"> <- </span>render screen, result
<span class="Constant"> <editor-initialization></span>
]
<span class="muRecipe">def</span> insert-text editor:&:editor, text:text<span class="muRecipe"> -> </span>editor:&:editor [
<span class="Constant">local-scope</span>
<span class="Constant">load-ingredients</span>
<span class="Comment"># early exit if text is empty</span>
<span class="muControl">return-unless</span> text, editor/same-as-ingredient:<span class="Constant">0</span>
len:num<span class="Special"> <- </span>length *text
<span class="muControl">return-unless</span> len, editor/same-as-ingredient:<span class="Constant">0</span>
idx:num<span class="Special"> <- </span>copy <span class="Constant">0</span>
<span class="Comment"># now we can start appending the rest, character by character</span>
curr:&:duplex-list:char<span class="Special"> <- </span>get *editor, <span class="Constant">data:offset</span>
<span class="Delimiter">{</span>
done?:bool<span class="Special"> <- </span>greater-or-equal idx, len
<span class="muControl">break-if</span> done?
c:char<span class="Special"> <- </span>index *text, idx
insert c, curr
<span class="Comment"># next iter</span>
curr<span class="Special"> <- </span>next curr
idx<span class="Special"> <- </span>add idx, <span class="Constant">1</span>
<span class="muControl">loop</span>
<span class="Delimiter">}</span>
<span class="muControl">return</span> editor/same-as-ingredient:<span class="Constant">0</span>
]
<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>:&:editor<span class="Special"> <- </span>new-editor <span class="Constant">0/data</span>, screen:&:screen, <span class="Constant">2/left</span>, <span class="Constant">5/right</span>
<span class="Constant">2</span>:editor<span class="Special"> <- </span>copy *<span class="Constant">1</span>:&:editor
]
memory-should-contain [
<span class="Comment"># 2 (data) <- just the § sentinel</span>
<span class="Comment"># 3 (top of screen) <- the § sentinel</span>
<span class="Constant">4</span><span class="Special"> <- </span><span class="Constant">0</span> <span class="Comment"># bottom-of-screen; null since text fits on screen</span>
<span class="Comment"># 5 (before cursor) <- the § sentinel</span>
<span class="Constant">6</span><span class="Special"> <- </span><span class="Constant">2</span> <span class="Comment"># left</span>
<span class="Constant">7</span><span class="Special"> <- </span><span class="Constant">4</span> <span class="Comment"># right (inclusive)</span>
<span class="Constant">8</span><span class="Special"> <- </span><span class="Constant">1</span> <span class="Comment"># bottom</span>
<span class="Constant">9</span><span class="Special"> <- </span><span class="Constant">1</span> <span class="Comment"># cursor row</span>
<span class="Constant">10</span><span class="Special"> <- </span><span class="Constant">2</span> <span class="Comment"># cursor column</span>
]
screen-should-contain [
<span class="Constant"> . .</span>
<span class="Constant"> . .</span>
<span class="Constant"> . .</span>
]
]
<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:&:screen, editor:&:editor<span class="muRecipe"> -> </span>last-row:num, last-column:num, screen:&:screen, editor:&: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>
left:num<span class="Special"> <- </span>get *editor, <span class="Constant">left:offset</span>
screen-height:num<span class="Special"> <- </span>screen-height screen
right:num<span class="Special"> <- </span>get *editor, <span class="Constant">right:offset</span>
<span class="Comment"># traversing editor</span>
curr:&:duplex-list:char<span class="Special"> <- </span>get *editor, <span class="Constant">top-of-screen:offset</span>
prev:&:duplex-list:char<span class="Special"> <- </span>copy curr <span class="Comment"># just in case curr becomes null and we can't compute prev</span>
curr<span class="Special"> <- </span>next curr
<span class="Comment"># traversing screen</span>
<span class="Constant"> +render-loop-initialization</span>
color:num<span class="Special"> <- </span>copy <span class="Constant">7/white</span>
row:num<span class="Special"> <- </span>copy <span class="Constant">1/top</span>
column:num<span class="Special"> <- </span>copy left
cursor-row:num<span class="Special"> <- </span>get *editor, <span class="Constant">cursor-row:offset</span>
cursor-column:num<span class="Special"> <- </span>get *editor, <span class="Constant">cursor-column:offset</span>
before-cursor:&:duplex-list:char<span class="Special"> <- </span>get *editor, <span class="Constant">before-cursor:offset</span>
screen<span class="Special"> <- </span>move-cursor screen, row, column
<span class="Delimiter">{</span>
<span class="Constant"> +next-character</span>
<span class="muControl">break-unless</span> curr
off-screen?:bool<span class="Special"> <- </span>greater-or-equal row, screen-height
<span class="muControl">break-if</span> off-screen?
<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>
at-cursor-row?:bool<span class="Special"> <- </span>equal row, cursor-row
<span class="muControl">break-unless</span> at-cursor-row?
at-cursor?:bool<span class="Special"> <- </span>equal column, cursor-column
<span class="muControl">break-unless</span> at-cursor?
before-cursor<span class="Special"> <- </span>copy prev
<span class="Delimiter">}</span>
c:char<span class="Special"> <- </span>get *curr, <span class="Constant">value:offset</span>
<span class="Constant"> <character-c-received></span>
<span class="Delimiter">{</span>
<span class="Comment"># newline? move to left rather than 0</span>
newline?:bool<span class="Special"> <- </span>equal c, <span class="Constant">10/newline</span>
<span class="muControl">break-unless</span> newline?
<span class="Comment"># adjust cursor if necessary</span>
<span class="Delimiter">{</span>
at-cursor-row?:bool<span class="Special"> <- </span>equal row, cursor-row
<span class="muControl">break-unless</span> at-cursor-row?
left-of-cursor?:bool<span class="Special"> <- </span>lesser-than column, cursor-column
<span class="muControl">break-unless</span> left-of-cursor?
cursor-column<span class="Special"> <- </span>copy column
before-cursor<span class="Special"> <- </span>prev curr
<span class="Delimiter">}</span>
<span class="Comment"># clear rest of line in this window</span>
clear-line-until screen, right
<span class="Comment"># skip to next line</span>
row<span class="Special"> <- </span>add row, <span class="Constant">1</span>
column<span class="Special"> <- </span>copy left
screen<span class="Special"> <- </span>move-cursor screen, row, column
curr<span class="Special"> <- </span>next curr
prev<span class="Special"> <- </span>next prev
<span class="muControl">loop</span> <span class="Constant">+next-character:label</span>
<span class="Delimiter">}</span>
<span class="Delimiter">{</span>
<span class="Comment"># at right? wrap. even if there's only one more letter left; we need</span>
<span class="Comment"># room for clicking on the cursor after it.</span>
at-right?:bool<span class="Special"> <- </span>equal column, right
<span class="muControl">break-unless</span> at-right?
<span class="Comment"># print wrap icon</span>
wrap-icon:char<span class="Special"> <- </span>copy <span class="Constant">8617/loop-back-to-left</span>
print screen, wrap-icon, <span class="Constant">245/grey</span>
column<span class="Special"> <- </span>copy left
row<span class="Special"> <- </span>add row, <span class="Constant">1</span>
screen<span class="Special"> <- </span>move-cursor screen, row, column
<span class="Comment"># don't increment curr</span>
<span class="muControl">loop</span> <span class="Constant">+next-character:label</span>
<span class="Delimiter">}</span>
print screen, c, color
curr<span class="Special"> <- </span>next curr
prev<span class="Special"> <- </span>next prev
column<span class="Special"> <- </span>add column, <span class="Constant">1</span>
<span class="muControl">loop</span>
<span class="Delimiter">}</span>
<span class="Comment"># save first character off-screen</span>
*editor<span class="Special"> <- </span>put *editor, <span class="Constant">bottom-of-screen:offset</span>, curr
<span class="Comment"># is cursor to the right of the last line? move to end</span>
<span class="Delimiter">{</span>
at-cursor-row?:bool<span class="Special"> <- </span>equal row, cursor-row
cursor-outside-line?:bool<span class="Special"> <- </span>lesser-or-equal column, cursor-column
before-cursor-on-same-line?:bool<span class="Special"> <- </span>and at-cursor-row?, cursor-outside-line?
above-cursor-row?:bool<span class="Special"> <- </span>lesser-than row, cursor-row
before-cursor?:bool<span class="Special"> <- </span>or before-cursor-on-same-line?, above-cursor-row?
<span class="muControl">break-unless</span> before-cursor?
cursor-row<span class="Special"> <- </span>copy row
cursor-column<span class="Special"> <- </span>copy column
before-cursor<span class="Special"> <- </span>copy prev
<span class="Delimiter">}</span>
*editor<span class="Special"> <- </span>put *editor, <span class="Constant">bottom:offset</span>, row
*editor<span class="Special"> <- </span>put *editor, <span class="Constant">cursor-row:offset</span>, cursor-row
*editor<span class="Special"> <- </span>put *editor, <span class="Constant">cursor-column:offset</span>, cursor-column
*editor<span class="Special"> <- </span>put *editor, <span class="Constant">before-cursor:offset</span>, before-cursor
<span class="muControl">return</span> row, column, screen/same-as-ingredient:<span class="Constant">0</span>, editor/same-as-ingredient:<span class="Constant">1</span>
]
<span class="muRecipe">def</span> clear-screen-from screen:&:screen, row:num, column:num, left:num, right:num<span class="muRecipe"> -> </span>screen:&:screen [
<span class="Constant">local-scope</span>
<span class="Constant">load-ingredients</span>
<span class="Comment"># if it's the real screen, use the optimized primitive</span>
<span class="Delimiter">{</span>
<span class="muControl">break-if</span> screen
clear-display-from row, column, left, right
<span class="muControl">return</span> screen/same-as-ingredient:<span class="Constant">0</span>
<span class="Delimiter">}</span>
<span class="Comment"># if not, go the slower route</span>
screen<span class="Special"> <- </span>move-cursor screen, row, column
clear-line-until screen, right
clear-rest-of-screen screen, row, left, right
<span class="muControl">return</span> screen/same-as-ingredient:<span class="Constant">0</span>
]
<span class="muRecipe">def</span> clear-rest-of-screen screen:&:screen, row:num, left:num, right:num<span class="muRecipe"> -> </span>screen:&:screen [
<span class="Constant">local-scope</span>
<span class="Constant">load-ingredients</span>
row<span class="Special"> <- </span>add row, <span class="Constant">1</span>
screen<span class="Special"> <- </span>move-cursor screen, row, left
screen-height:num<span class="Special"> <- </span>screen-height screen
<span class="Delimiter">{</span>
at-bottom-of-screen?:bool<span class="Special"> <- </span>greater-or-equal row, screen-height
<span class="muControl">break-if</span> at-bottom-of-screen?
screen<span class="Special"> <- </span>move-cursor screen, row, left
clear-line-until screen, right
row<span class="Special"> <- </span>add row, <span class="Constant">1</span>
<span class="muControl">loop</span>
<span class="Delimiter">}</span>
]
<span class="muScenario">scenario</span> editor-initially-prints-multiple-lines [
assume-screen <span class="Constant">5/width</span>, <span class="Constant">5/height</span>
run [
s:text<span class="Special"> <- </span>new <span class="Constant">[abc</span>
<span class="Constant">def]</span>
new-editor s:text, screen:&: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>
<span class="Constant"> .def .</span>
<span class="Constant"> . .</span>
]
]
<span class="muScenario">scenario</span> editor-initially-handles-offsets [
assume-screen <span class="Constant">5/width</span>, <span class="Constant">5/height</span>
run [
s:text<span class="Special"> <- </span>new <span class="Constant">[abc]</span>
new-editor s:text, screen:&:screen, <span class="Constant">1/left</span>, <span class="Constant">5/right</span>
]
screen-should-contain [
<span class="Constant"> . .</span>
<span class="Constant"> . abc .</span>
<span class="Constant"> . .</span>
]
]
<span class="muScenario">scenario</span> editor-initially-prints-multiple-lines-at-offset [
assume-screen <span class="Constant">5/width</span>, <span class="Constant">5/height</span>
run [
s:text<span class="Special"> <- </span>new <span class="Constant">[abc</span>
<span class="Constant">def]</span>
new-editor s:text, screen:&:screen, <span class="Constant">1/left</span>, <span class="Constant">5/right</span>
]
screen-should-contain [
<span class="Constant"> . .</span>
<span class="Constant"> . abc .</span>
<span class="Constant"> . def .</span>
<span class="Constant"> . .</span>
]
]
<span class="muScenario">scenario</span> editor-initially-wraps-long-lines [
assume-screen <span class="Constant">5/width</span>, <span class="Constant">5/height</span>
run [
s:text<span class="Special"> <- </span>new <span class="Constant">[abc def]</span>
new-editor s:text, screen:&: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>
<span class="Constant"> .def .</span>
<span class="Constant"> . .</span>
]
screen-should-contain-in-color <span class="Constant">245/grey</span> [
<span class="Constant"> . .</span>
<span class="Constant"> . ↩.</span>
<span class="Constant"> . .</span>
<span class="Constant"> . .</span>
]
]
<span class="muScenario">scenario</span> editor-initially-wraps-barely-long-lines [
assume-screen <span class="Constant">5/width</span>, <span class="Constant">5/height</span>
run [
s:text<span class="Special"> <- </span>new <span class="Constant">[abcde]</span>
new-editor s:text, screen:&:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
]
<span class="Comment"># still wrap, even though the line would fit. We need room to click on the</span>
<span class="Comment"># end of the line</span>
screen-should-contain [
<span class="Constant"> . .</span>
<span class="Constant"> .abcd↩.</span>
<span class="Constant"> .e .</span>
<span class="Constant"> . .</span>
]
screen-should-contain-in-color <span class="Constant">245/grey</span> [
<span class="Constant"> . .</span>
<span class="Constant"> . ↩.</span>
<span class="Constant"> . .</span>
<span class="Constant"> . .</span>
]
]
<span class="muScenario">scenario</span> editor-initializes-empty-text [
assume-screen <span class="Constant">5/width</span>, <span class="Constant">5/height</span>
run [
<span class="Constant">1</span>:text<span class="Special"> <- </span>new <span class="Constant">[]</span>
<span class="Constant">2</span>:&:editor<span class="Special"> <- </span>new-editor <span class="Constant">1</span>:text, screen:&:screen, <span class="Constant">0/left</span>, <span class="Constant">5/right</span>
<span class="Constant">3</span>:num<span class="Special"> <- </span>get *<span class="Constant">2</span>:&:editor, <span class="Constant">cursor-row:offset</span>
<span class="Constant">4</span>:num<span class="Special"> <- </span>get *<span class="Constant">2</span>:&:editor, <span class="Constant">cursor-column:offset</span>
]
screen-should-contain [
<span class="Constant"> . .</span>
<span class="Constant"> . .</span>
<span class="Constant"> . .</span>
]
memory-should-contain [
<span class="Constant">3</span><span class="Special"> <- </span><span class="Constant">1</span> <span class="Comment"># cursor row</span>
<span class="Constant">4</span><span class="Special"> <- </span><span class="Constant">0</span> <span class="Comment"># cursor column</span>
]
]
<span class="Comment"># just a little color for mu code</span>
<span class="muScenario">scenario</span> render-colors-comments [
assume-screen <span class="Constant">5/width</span>, <span class="Constant">5/height</span>
run [
s:text<span class="Special"> <- </span>new <span class="Constant">[abc</span>
<span class="Constant"># de</span>
<span class="Constant">f]</span>
new-editor s:text, screen:&: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>
<span class="Constant"> .# de .</span>
<span class="Constant"> .f .</span>
<span class="Constant"> . .</span>
]
screen-should-contain-in-color <span class="Constant">12/lightblue</span>, [
<span class="Constant"> . .</span>
<span class="Constant"> . .</span>
<span class="Constant"> .# de .</span>
<span class="Constant"> . .</span>
<span class="Constant"> . .</span>
]
screen-should-contain-in-color <span class="Constant">7/white</span>, [
<span class="Constant"> . .</span>
<span class="Constant"> .abc .</span>
<span class="Constant"> . .</span>
<span class="Constant"> .f .</span>
<span class="Constant"> . .</span>
]
]
<span class="muRecipe">after</span> <span class="Constant"><character-c-received></span> [
color<span class="Special"> <- </span>get-color color, c
]
<span class="Comment"># so far the previous color is all the information we need; that may change</span>
<span class="muRecipe">def</span> get-color color:num, c:char<span class="muRecipe"> -> </span>color:num [
<span class="Constant">local-scope</span>
<span class="Constant">load-ingredients</span>
color-is-white?:bool<span class="Special"> <- </span>equal color, <span class="Constant">7/white</span>
<span class="Comment"># if color is white and next character is '#', switch color to blue</span>
<span class="Delimiter">{</span>
<span class="muControl">break-unless</span> color-is-white?
starting-comment?:bool<span class="Special"> <- </span>equal c, <span class="Constant">35/#</span>
<span class="muControl">break-unless</span> starting-comment?
trace <span class="Constant">90</span>, <span class="Constant">[app]</span>, <span class="Constant">[switch color back to blue]</span>
color<span class="Special"> <- </span>copy <span class="Constant">12/lightblue</span>
<span class="muControl">jump</span> <span class="Constant">+exit:label</span>
<span class="Delimiter">}</span>
<span class="Comment"># if color is blue and next character is newline, switch color to white</span>
<span class="Delimiter">{</span>
color-is-blue?:bool<span class="Special"> <- </span>equal color, <span class="Constant">12/lightblue</span>
<span class="muControl">break-unless</span> color-is-blue?
ending-comment?:bool<span class="Special"> <- </span>equal c, <span class="Constant">10/newline</span>
<span class="muControl">break-unless</span> ending-comment?
trace <span class="Constant">90</span>, <span class="Constant">[app]</span>, <span class="Constant">[switch color back to white]</span>
color<span class="Special"> <- </span>copy <span class="Constant">7/white</span>
<span class="muControl">jump</span> <span class="Constant">+exit:label</span>
<span class="Delimiter">}</span>
<span class="Comment"># if color is white (no comments) and next character is '<', switch color to red</span>
<span class="Delimiter">{</span>
<span class="muControl">break-unless</span> color-is-white?
starting-assignment?:bool<span class="Special"> <- </span>equal c, <span class="Constant">60/<</span>
<span class="muControl">break-unless</span> starting-assignment?
color<span class="Special"> <- </span>copy <span class="Constant">1/red</span>
<span class="muControl">jump</span> <span class="Constant">+exit:label</span>
<span class="Delimiter">}</span>
<span class="Comment"># if color is red and next character is space, switch color to white</span>
<span class="Delimiter">{</span>
color-is-red?:bool<span class="Special"> <- </span>equal color, <span class="Constant">1/red</span>
<span class="muControl">break-unless</span> color-is-red?
ending-assignment?:bool<span class="Special"> <- </span>equal c, <span class="Constant">32/space</span>
<span class="muControl">break-unless</span> ending-assignment?
color<span class="Special"> <- </span>copy <span class="Constant">7/white</span>
<span class="muControl">jump</span> <span class="Constant">+exit:label</span>
<span class="Delimiter">}</span>
<span class="Comment"># otherwise no change</span>
<span class="Constant"> +exit</span>
<span class="muControl">return</span> color
]
<span class="muScenario">scenario</span> render-colors-assignment [
assume-screen <span class="Constant">8/width</span>, <span class="Constant">5/height</span>
run [
s:text<span class="Special"> <- </span>new <span class="Constant">[abc</span>
<span class="Constant">d <- e</span>
<span class="Constant">f]</span>
new-editor s:text, screen:&:screen, <span class="Constant">0/left</span>, <span class="Constant">8/right</span>
]
screen-should-contain [
<span class="Constant"> . .</span>
<span class="Constant"> .abc .</span>
<span class="Constant"> .d <- e .</span>
<span class="Constant"> .f .</span>
<span class="Constant"> . .</span>
]
screen-should-contain-in-color <span class="Constant">1/red</span>, [
<span class="Constant"> . .</span>
<span class="Constant"> . .</span>
<span class="Constant"> . <- .</span>
<span class="Constant"> . .</span>
<span class="Constant"> . .</span>
]
]
</pre>
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