2423 - describe shape-shifting in html docs

1 files changed, 150 insertions, 71 deletions

diff --git a/html/032array.cc.html b/html/032array.cc.html
index c73052a4..8c0ce105 100644
--- a/html/032array.cc.html
+++ b/html/032array.cc.html
@@ -13,6 +13,7 @@
 pre { white-space: pre-wrap; font-family: monospace; color: #eeeeee; background-color: #080808; }
 body { font-family: monospace; color: #eeeeee; background-color: #080808; }
 * { font-size: 1.05em; }
+.traceContains { color: #008000; }
 .SalientComment { color: #00ffff; }
 .cSpecial { color: #008000; }
 .Comment { color: #9090ff; }
@@ -20,7 +21,6 @@ body { font-family: monospace; color: #eeeeee; background-color: #080808; }
 .Special { color: #ff6060; }
 .Identifier { color: #804000; }
 .Constant { color: #00a0a0; }
-.traceContains { color: #008000; }
 -->
 </style>
 
@@ -50,40 +50,47 @@ recipe main [
 <span class="Delimiter">:(before &quot;End Primitive Recipe Declarations&quot;)</span>
 CREATE_ARRAY<span class="Delimiter">,</span>
 <span class="Delimiter">:(before &quot;End Primitive Recipe Numbers&quot;)</span>
-Recipe_ordinal[<span class="Constant">&quot;create-array&quot;</span>] = CREATE_ARRAY<span class="Delimiter">;</span>
-<span class="Delimiter">:(before &quot;End Primitive Recipe Implementations&quot;)</span>
+put<span class="Delimiter">(</span>Recipe_ordinal<span class="Delimiter">,</span> <span class="Constant">&quot;create-array&quot;</span><span class="Delimiter">,</span> CREATE_ARRAY<span class="Delimiter">);</span>
+<span class="Delimiter">:(before &quot;End Primitive Recipe Checks&quot;)</span>
 case CREATE_ARRAY: <span class="Delimiter">{</span>
-  if <span class="Delimiter">(</span>current_instruction<span class="Delimiter">().</span>products<span class="Delimiter">.</span>empty<span class="Delimiter">())</span> <span class="Delimiter">{</span>
-    raise &lt;&lt; current_recipe_name <span class="Delimiter">()</span> &lt;&lt; <span class="Constant">&quot;: 'create-array' needs one product and no ingredients but got '&quot;</span> &lt;&lt; current_instruction<span class="Delimiter">().</span>to_string<span class="Delimiter">()</span> &lt;&lt; <span class="cSpecial">'\n'</span> &lt;&lt; end<span class="Delimiter">();</span>
+  if <span class="Delimiter">(</span>inst<span class="Delimiter">.</span>products<span class="Delimiter">.</span>empty<span class="Delimiter">())</span> <span class="Delimiter">{</span>
+    raise_error &lt;&lt; maybe<span class="Delimiter">(</span>get<span class="Delimiter">(</span>Recipe<span class="Delimiter">,</span> r<span class="Delimiter">).</span>name<span class="Delimiter">)</span> &lt;&lt; <span class="Constant">&quot;'create-array' needs one product and no ingredients but got '&quot;</span> &lt;&lt; inst<span class="Delimiter">.</span>to_string<span class="Delimiter">()</span> &lt;&lt; <span class="cSpecial">'\n'</span> &lt;&lt; end<span class="Delimiter">();</span>
     <span class="Identifier">break</span><span class="Delimiter">;</span>
   <span class="Delimiter">}</span>
-  reagent product = canonize<span class="Delimiter">(</span>current_instruction<span class="Delimiter">().</span>products<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">));</span>
+  reagent product = inst<span class="Delimiter">.</span>products<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">);</span>
+  canonize_type<span class="Delimiter">(</span>product<span class="Delimiter">);</span>
   if <span class="Delimiter">(</span>!is_mu_array<span class="Delimiter">(</span>product<span class="Delimiter">))</span> <span class="Delimiter">{</span>
-    raise &lt;&lt; current_recipe_name <span class="Delimiter">()</span> &lt;&lt; <span class="Constant">&quot;: 'create-array' cannot create non-array &quot;</span> &lt;&lt; product<span class="Delimiter">.</span>original_string &lt;&lt; <span class="cSpecial">'\n'</span> &lt;&lt; end<span class="Delimiter">();</span>
+    raise_error &lt;&lt; maybe<span class="Delimiter">(</span>get<span class="Delimiter">(</span>Recipe<span class="Delimiter">,</span> r<span class="Delimiter">).</span>name<span class="Delimiter">)</span> &lt;&lt; <span class="Constant">&quot;'create-array' cannot create non-array &quot;</span> &lt;&lt; product<span class="Delimiter">.</span>original_string &lt;&lt; <span class="cSpecial">'\n'</span> &lt;&lt; end<span class="Delimiter">();</span>
     <span class="Identifier">break</span><span class="Delimiter">;</span>
   <span class="Delimiter">}</span>
-  long long int base_address = product<span class="Delimiter">.</span>value<span class="Delimiter">;</span>
-  if <span class="Delimiter">(</span>SIZE<span class="Delimiter">(</span>product<span class="Delimiter">.</span>types<span class="Delimiter">)</span> == <span class="Constant">1</span><span class="Delimiter">)</span> <span class="Delimiter">{</span>
-    raise &lt;&lt; current_recipe_name <span class="Delimiter">()</span> &lt;&lt; <span class="Constant">&quot;: create array of what? &quot;</span> &lt;&lt; current_instruction<span class="Delimiter">().</span>to_string<span class="Delimiter">()</span> &lt;&lt; <span class="cSpecial">'\n'</span> &lt;&lt; end<span class="Delimiter">();</span>
+  if <span class="Delimiter">(</span>!product<span class="Delimiter">.</span>type<span class="Delimiter">-&gt;</span>right<span class="Delimiter">)</span> <span class="Delimiter">{</span>
+    raise_error &lt;&lt; maybe<span class="Delimiter">(</span>get<span class="Delimiter">(</span>Recipe<span class="Delimiter">,</span> r<span class="Delimiter">).</span>name<span class="Delimiter">)</span> &lt;&lt; <span class="Constant">&quot;create array of what? &quot;</span> &lt;&lt; inst<span class="Delimiter">.</span>to_string<span class="Delimiter">()</span> &lt;&lt; <span class="cSpecial">'\n'</span> &lt;&lt; end<span class="Delimiter">();</span>
     <span class="Identifier">break</span><span class="Delimiter">;</span>
   <span class="Delimiter">}</span>
   <span class="Comment">// 'create-array' will need to check properties rather than types</span>
-  if <span class="Delimiter">(</span>SIZE<span class="Delimiter">(</span>product<span class="Delimiter">.</span>properties<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">).</span>second<span class="Delimiter">)</span> &lt;= <span class="Constant">2</span><span class="Delimiter">)</span> <span class="Delimiter">{</span>
-    raise &lt;&lt; current_recipe_name <span class="Delimiter">()</span> &lt;&lt; <span class="Constant">&quot;: create array of what size? &quot;</span> &lt;&lt; current_instruction<span class="Delimiter">().</span>to_string<span class="Delimiter">()</span> &lt;&lt; <span class="cSpecial">'\n'</span> &lt;&lt; end<span class="Delimiter">();</span>
+  if <span class="Delimiter">(</span>!product<span class="Delimiter">.</span>properties<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">).</span>second || !product<span class="Delimiter">.</span>properties<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">).</span>second<span class="Delimiter">-&gt;</span>right || !product<span class="Delimiter">.</span>properties<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">).</span>second<span class="Delimiter">-&gt;</span>right<span class="Delimiter">-&gt;</span>right<span class="Delimiter">)</span> <span class="Delimiter">{</span>
+    raise_error &lt;&lt; maybe<span class="Delimiter">(</span>get<span class="Delimiter">(</span>Recipe<span class="Delimiter">,</span> r<span class="Delimiter">).</span>name<span class="Delimiter">)</span> &lt;&lt; <span class="Constant">&quot;create array of what size? &quot;</span> &lt;&lt; inst<span class="Delimiter">.</span>to_string<span class="Delimiter">()</span> &lt;&lt; <span class="cSpecial">'\n'</span> &lt;&lt; end<span class="Delimiter">();</span>
     <span class="Identifier">break</span><span class="Delimiter">;</span>
   <span class="Delimiter">}</span>
-  if <span class="Delimiter">(</span>!is_integer<span class="Delimiter">(</span>product<span class="Delimiter">.</span>properties<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">).</span>second<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">2</span><span class="Delimiter">)))</span> <span class="Delimiter">{</span>
-    raise &lt;&lt; current_recipe_name <span class="Delimiter">()</span> &lt;&lt; <span class="Constant">&quot;: 'create-array' product should specify size of array after its element type, but got &quot;</span> &lt;&lt; product<span class="Delimiter">.</span>properties<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">).</span>second<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">2</span><span class="Delimiter">)</span> &lt;&lt; <span class="cSpecial">'\n'</span> &lt;&lt; end<span class="Delimiter">();</span>
+  if <span class="Delimiter">(</span>!is_integer<span class="Delimiter">(</span>product<span class="Delimiter">.</span>properties<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">).</span>second<span class="Delimiter">-&gt;</span>right<span class="Delimiter">-&gt;</span>right<span class="Delimiter">-&gt;</span>value<span class="Delimiter">))</span> <span class="Delimiter">{</span>
+    raise_error &lt;&lt; maybe<span class="Delimiter">(</span>get<span class="Delimiter">(</span>Recipe<span class="Delimiter">,</span> r<span class="Delimiter">).</span>name<span class="Delimiter">)</span> &lt;&lt; <span class="Constant">&quot;'create-array' product should specify size of array after its element type, but got &quot;</span> &lt;&lt; product<span class="Delimiter">.</span>properties<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">).</span>second<span class="Delimiter">-&gt;</span>right<span class="Delimiter">-&gt;</span>right<span class="Delimiter">-&gt;</span>value &lt;&lt; <span class="cSpecial">'\n'</span> &lt;&lt; end<span class="Delimiter">();</span>
     <span class="Identifier">break</span><span class="Delimiter">;</span>
   <span class="Delimiter">}</span>
-  long long int array_size= to_integer<span class="Delimiter">(</span>product<span class="Delimiter">.</span>properties<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">).</span>second<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">2</span><span class="Delimiter">));</span>
+  <span class="Identifier">break</span><span class="Delimiter">;</span>
+<span class="Delimiter">}</span>
+<span class="Delimiter">:(before &quot;End Primitive Recipe Implementations&quot;)</span>
+case CREATE_ARRAY: <span class="Delimiter">{</span>
+  reagent product = current_instruction<span class="Delimiter">().</span>products<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">);</span>
+  canonize<span class="Delimiter">(</span>product<span class="Delimiter">);</span>
+  long long int base_address = product<span class="Delimiter">.</span>value<span class="Delimiter">;</span>
+  long long int array_size = to_integer<span class="Delimiter">(</span>product<span class="Delimiter">.</span>properties<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">).</span>second<span class="Delimiter">-&gt;</span>right<span class="Delimiter">-&gt;</span>right<span class="Delimiter">-&gt;</span>value<span class="Delimiter">);</span>
   <span class="Comment">// initialize array size, so that size_of will work</span>
-  Memory[base_address] = array_size<span class="Delimiter">;</span>  <span class="Comment">// in array elements</span>
+  put<span class="Delimiter">(</span>Memory<span class="Delimiter">,</span> base_address<span class="Delimiter">,</span> array_size<span class="Delimiter">);</span>  <span class="Comment">// in array elements</span>
   long long int size = size_of<span class="Delimiter">(</span>product<span class="Delimiter">);</span>  <span class="Comment">// in locations</span>
-  trace<span class="Delimiter">(</span><span class="Constant">&quot;run&quot;</span><span class="Delimiter">)</span> &lt;&lt; <span class="Constant">&quot;creating array of size &quot;</span> &lt;&lt; size &lt;&lt; <span class="cSpecial">'\n'</span> &lt;&lt; end<span class="Delimiter">();</span>
+  trace<span class="Delimiter">(</span><span class="Constant">9998</span><span class="Delimiter">,</span> <span class="Constant">&quot;run&quot;</span><span class="Delimiter">)</span> &lt;&lt; <span class="Constant">&quot;creating array of size &quot;</span> &lt;&lt; size &lt;&lt; <span class="cSpecial">'\n'</span> &lt;&lt; end<span class="Delimiter">();</span>
   <span class="Comment">// initialize array</span>
   for <span class="Delimiter">(</span>long long int i = <span class="Constant">1</span><span class="Delimiter">;</span> i &lt;= size_of<span class="Delimiter">(</span>product<span class="Delimiter">);</span> ++i<span class="Delimiter">)</span> <span class="Delimiter">{</span>
-    Memory[base_address+i] = <span class="Constant">0</span><span class="Delimiter">;</span>
+    put<span class="Delimiter">(</span>Memory<span class="Delimiter">,</span> base_address+i<span class="Delimiter">,</span> <span class="Constant">0</span><span class="Delimiter">);</span>
   <span class="Delimiter">}</span>
   <span class="Comment">// dummy product; doesn't actually do anything</span>
   products<span class="Delimiter">.</span>resize<span class="Delimiter">(</span><span class="Constant">1</span><span class="Delimiter">);</span>
@@ -112,7 +119,7 @@ recipe main [
   <span class="Constant">2</span>:number<span class="Special"> &lt;- </span>copy <span class="Constant">14</span>
   <span class="Constant">3</span>:number<span class="Special"> &lt;- </span>copy <span class="Constant">15</span>
   <span class="Constant">4</span>:number<span class="Special"> &lt;- </span>copy <span class="Constant">16</span>
-  <span class="Constant">5</span>:address:array:number<span class="Special"> &lt;- </span>copy <span class="Constant">1</span>  <span class="Comment"># unsafe</span>
+  <span class="Constant">5</span>:address:array:number<span class="Special"> &lt;- </span>copy <span class="Constant">1</span>/<span class="Special">raw</span>
   <span class="Constant">6</span>:array:number<span class="Special"> &lt;- </span>copy *<span class="Constant">5</span>:address:array:number
 ]
 <span class="traceContains">+mem: storing 3 in location 6</span>
@@ -132,15 +139,15 @@ recipe main [
 
 <span class="Comment">//: disable the size mismatch check since the destination array need not be initialized</span>
 <span class="Delimiter">:(before &quot;End size_mismatch(x) Cases&quot;)</span>
-if <span class="Delimiter">(</span>x<span class="Delimiter">.</span>types<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">)</span> == Type_ordinal[<span class="Constant">&quot;array&quot;</span>]<span class="Delimiter">)</span> <span class="Identifier">return</span> <span class="Constant">false</span><span class="Delimiter">;</span>
+if <span class="Delimiter">(</span>x<span class="Delimiter">.</span>type &amp;&amp; x<span class="Delimiter">.</span>type<span class="Delimiter">-&gt;</span>value == get<span class="Delimiter">(</span>Type_ordinal<span class="Delimiter">,</span> <span class="Constant">&quot;array&quot;</span><span class="Delimiter">))</span> <span class="Identifier">return</span> <span class="Constant">false</span><span class="Delimiter">;</span>
 <span class="Delimiter">:(before &quot;End size_of(reagent) Cases&quot;)</span>
-if <span class="Delimiter">(</span>r<span class="Delimiter">.</span>types<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">)</span> == Type_ordinal[<span class="Constant">&quot;array&quot;</span>]<span class="Delimiter">)</span> <span class="Delimiter">{</span>
-  if <span class="Delimiter">(</span>SIZE<span class="Delimiter">(</span>r<span class="Delimiter">.</span>types<span class="Delimiter">)</span> == <span class="Constant">1</span><span class="Delimiter">)</span> <span class="Delimiter">{</span>
-    raise &lt;&lt; current_recipe_name<span class="Delimiter">()</span> &lt;&lt; <span class="Constant">&quot;: '&quot;</span> &lt;&lt; r<span class="Delimiter">.</span>original_string &lt;&lt; <span class="Constant">&quot;' is an array of what?</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span> &lt;&lt; end<span class="Delimiter">();</span>
+if <span class="Delimiter">(</span>r<span class="Delimiter">.</span>type &amp;&amp; r<span class="Delimiter">.</span>type<span class="Delimiter">-&gt;</span>value == get<span class="Delimiter">(</span>Type_ordinal<span class="Delimiter">,</span> <span class="Constant">&quot;array&quot;</span><span class="Delimiter">))</span> <span class="Delimiter">{</span>
+  if <span class="Delimiter">(</span>!r<span class="Delimiter">.</span>type<span class="Delimiter">-&gt;</span>right<span class="Delimiter">)</span> <span class="Delimiter">{</span>
+    raise_error &lt;&lt; maybe<span class="Delimiter">(</span>current_recipe_name<span class="Delimiter">())</span> &lt;&lt; <span class="Constant">&quot;'&quot;</span> &lt;&lt; r<span class="Delimiter">.</span>original_string &lt;&lt; <span class="Constant">&quot;' is an array of what?</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span> &lt;&lt; end<span class="Delimiter">();</span>
     <span class="Identifier">return</span> <span class="Constant">1</span><span class="Delimiter">;</span>
   <span class="Delimiter">}</span>
   <span class="Comment">// skip the 'array' type to get at the element type</span>
-  <span class="Identifier">return</span> <span class="Constant">1</span> + Memory[r<span class="Delimiter">.</span>value]*size_of<span class="Delimiter">(</span>array_element<span class="Delimiter">(</span>r<span class="Delimiter">.</span>types<span class="Delimiter">));</span>
+  <span class="Identifier">return</span> <span class="Constant">1</span> + get_or_insert<span class="Delimiter">(</span>Memory<span class="Delimiter">,</span> r<span class="Delimiter">.</span>value<span class="Delimiter">)</span>*size_of<span class="Delimiter">(</span>array_element<span class="Delimiter">(</span>r<span class="Delimiter">.</span>type<span class="Delimiter">));</span>
 <span class="Delimiter">}</span>
 
 <span class="SalientComment">//:: To access elements of an array, use 'index'</span>
@@ -169,43 +176,60 @@ recipe main [
 <span class="Delimiter">:(before &quot;End Primitive Recipe Declarations&quot;)</span>
 INDEX<span class="Delimiter">,</span>
 <span class="Delimiter">:(before &quot;End Primitive Recipe Numbers&quot;)</span>
-Recipe_ordinal[<span class="Constant">&quot;index&quot;</span>] = INDEX<span class="Delimiter">;</span>
-<span class="Delimiter">:(before &quot;End Primitive Recipe Implementations&quot;)</span>
+put<span class="Delimiter">(</span>Recipe_ordinal<span class="Delimiter">,</span> <span class="Constant">&quot;index&quot;</span><span class="Delimiter">,</span> INDEX<span class="Delimiter">);</span>
+<span class="Delimiter">:(before &quot;End Primitive Recipe Checks&quot;)</span>
 case INDEX: <span class="Delimiter">{</span>
-  if <span class="Delimiter">(</span>SIZE<span class="Delimiter">(</span>current_instruction<span class="Delimiter">().</span>ingredients<span class="Delimiter">)</span> != <span class="Constant">2</span><span class="Delimiter">)</span> <span class="Delimiter">{</span>
-    raise &lt;&lt; current_recipe_name<span class="Delimiter">()</span> &lt;&lt; <span class="Constant">&quot;: 'index' expects exactly 2 ingredients in '&quot;</span> &lt;&lt; current_instruction<span class="Delimiter">().</span>to_string<span class="Delimiter">()</span> &lt;&lt; <span class="Constant">&quot;'</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span> &lt;&lt; end<span class="Delimiter">();</span>
+  if <span class="Delimiter">(</span>SIZE<span class="Delimiter">(</span>inst<span class="Delimiter">.</span>ingredients<span class="Delimiter">)</span> != <span class="Constant">2</span><span class="Delimiter">)</span> <span class="Delimiter">{</span>
+    raise_error &lt;&lt; maybe<span class="Delimiter">(</span>get<span class="Delimiter">(</span>Recipe<span class="Delimiter">,</span> r<span class="Delimiter">).</span>name<span class="Delimiter">)</span> &lt;&lt; <span class="Constant">&quot;'index' expects exactly 2 ingredients in '&quot;</span> &lt;&lt; inst<span class="Delimiter">.</span>to_string<span class="Delimiter">()</span> &lt;&lt; <span class="Constant">&quot;'</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span> &lt;&lt; end<span class="Delimiter">();</span>
     <span class="Identifier">break</span><span class="Delimiter">;</span>
   <span class="Delimiter">}</span>
-  reagent base = canonize<span class="Delimiter">(</span>current_instruction<span class="Delimiter">().</span>ingredients<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">));</span>
+  reagent base = inst<span class="Delimiter">.</span>ingredients<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">);</span>
+  canonize_type<span class="Delimiter">(</span>base<span class="Delimiter">);</span>
   if <span class="Delimiter">(</span>!is_mu_array<span class="Delimiter">(</span>base<span class="Delimiter">))</span> <span class="Delimiter">{</span>
-    raise &lt;&lt; current_recipe_name <span class="Delimiter">()</span> &lt;&lt; <span class="Constant">&quot;: 'index' on a non-array &quot;</span> &lt;&lt; base<span class="Delimiter">.</span>original_string &lt;&lt; <span class="cSpecial">'\n'</span> &lt;&lt; end<span class="Delimiter">();</span>
+    raise_error &lt;&lt; maybe<span class="Delimiter">(</span>get<span class="Delimiter">(</span>Recipe<span class="Delimiter">,</span> r<span class="Delimiter">).</span>name<span class="Delimiter">)</span> &lt;&lt; <span class="Constant">&quot;'index' on a non-array &quot;</span> &lt;&lt; base<span class="Delimiter">.</span>original_string &lt;&lt; <span class="cSpecial">'\n'</span> &lt;&lt; end<span class="Delimiter">();</span>
     <span class="Identifier">break</span><span class="Delimiter">;</span>
   <span class="Delimiter">}</span>
+  if <span class="Delimiter">(</span>inst<span class="Delimiter">.</span>products<span class="Delimiter">.</span>empty<span class="Delimiter">())</span> <span class="Identifier">break</span><span class="Delimiter">;</span>
+  reagent product = inst<span class="Delimiter">.</span>products<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">);</span>
+  canonize_type<span class="Delimiter">(</span>product<span class="Delimiter">);</span>
+  reagent element<span class="Delimiter">;</span>
+  element<span class="Delimiter">.</span>type = new type_tree<span class="Delimiter">(</span>*array_element<span class="Delimiter">(</span>base<span class="Delimiter">.</span>type<span class="Delimiter">));</span>
+  if <span class="Delimiter">(</span>!types_match<span class="Delimiter">(</span>product<span class="Delimiter">,</span> element<span class="Delimiter">))</span> <span class="Delimiter">{</span>
+    raise_error &lt;&lt; maybe<span class="Delimiter">(</span>get<span class="Delimiter">(</span>Recipe<span class="Delimiter">,</span> r<span class="Delimiter">).</span>name<span class="Delimiter">)</span> &lt;&lt; <span class="Constant">&quot;'index' on &quot;</span> &lt;&lt; base<span class="Delimiter">.</span>original_string &lt;&lt; <span class="Constant">&quot; can't be saved in &quot;</span> &lt;&lt; product<span class="Delimiter">.</span>original_string &lt;&lt; <span class="Constant">&quot;; type should be &quot;</span> &lt;&lt; debug_string<span class="Delimiter">(</span>element<span class="Delimiter">.</span>type<span class="Delimiter">)</span> &lt;&lt; <span class="cSpecial">'\n'</span> &lt;&lt; end<span class="Delimiter">();</span>
+    <span class="Identifier">break</span><span class="Delimiter">;</span>
+  <span class="Delimiter">}</span>
+  <span class="Identifier">break</span><span class="Delimiter">;</span>
+<span class="Delimiter">}</span>
+<span class="Delimiter">:(before &quot;End Primitive Recipe Implementations&quot;)</span>
+case INDEX: <span class="Delimiter">{</span>
+  reagent base = current_instruction<span class="Delimiter">().</span>ingredients<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">);</span>
+  canonize<span class="Delimiter">(</span>base<span class="Delimiter">);</span>
   long long int base_address = base<span class="Delimiter">.</span>value<span class="Delimiter">;</span>
   if <span class="Delimiter">(</span>base_address == <span class="Constant">0</span><span class="Delimiter">)</span> <span class="Delimiter">{</span>
-    raise &lt;&lt; current_recipe_name<span class="Delimiter">()</span> &lt;&lt; <span class="Constant">&quot;: tried to access location 0 in '&quot;</span> &lt;&lt; current_instruction<span class="Delimiter">().</span>to_string<span class="Delimiter">()</span> &lt;&lt; <span class="Constant">&quot;'</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span> &lt;&lt; end<span class="Delimiter">();</span>
+    raise_error &lt;&lt; maybe<span class="Delimiter">(</span>current_recipe_name<span class="Delimiter">())</span> &lt;&lt; <span class="Constant">&quot;tried to access location 0 in '&quot;</span> &lt;&lt; current_instruction<span class="Delimiter">().</span>to_string<span class="Delimiter">()</span> &lt;&lt; <span class="Constant">&quot;'</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span> &lt;&lt; end<span class="Delimiter">();</span>
     <span class="Identifier">break</span><span class="Delimiter">;</span>
   <span class="Delimiter">}</span>
-  reagent offset = canonize<span class="Delimiter">(</span>current_instruction<span class="Delimiter">().</span>ingredients<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">1</span><span class="Delimiter">));</span>
+  reagent offset = current_instruction<span class="Delimiter">().</span>ingredients<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">1</span><span class="Delimiter">);</span>
+  canonize<span class="Delimiter">(</span>offset<span class="Delimiter">);</span>
   vector&lt;double&gt; offset_val<span class="Delimiter">(</span>read_memory<span class="Delimiter">(</span>offset<span class="Delimiter">));</span>
-  vector&lt;type_ordinal&gt; element_type = array_element<span class="Delimiter">(</span>base<span class="Delimiter">.</span>types<span class="Delimiter">);</span>
-  if <span class="Delimiter">(</span>offset_val<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">)</span> &lt; <span class="Constant">0</span> || offset_val<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">)</span> &gt;= Memory[base_address]<span class="Delimiter">)</span> <span class="Delimiter">{</span>
-    raise &lt;&lt; current_recipe_name<span class="Delimiter">()</span> &lt;&lt; <span class="Constant">&quot;: invalid index &quot;</span> &lt;&lt; offset_val<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">)</span> &lt;&lt; <span class="cSpecial">'\n'</span> &lt;&lt; end<span class="Delimiter">();</span>
+  type_tree* element_type = array_element<span class="Delimiter">(</span>base<span class="Delimiter">.</span>type<span class="Delimiter">);</span>
+  if <span class="Delimiter">(</span>offset_val<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">)</span> &lt; <span class="Constant">0</span> || offset_val<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">)</span> &gt;= get_or_insert<span class="Delimiter">(</span>Memory<span class="Delimiter">,</span> base_address<span class="Delimiter">))</span> <span class="Delimiter">{</span>
+    raise_error &lt;&lt; maybe<span class="Delimiter">(</span>current_recipe_name<span class="Delimiter">())</span> &lt;&lt; <span class="Constant">&quot;invalid index &quot;</span> &lt;&lt; no_scientific<span class="Delimiter">(</span>offset_val<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">))</span> &lt;&lt; <span class="cSpecial">'\n'</span> &lt;&lt; end<span class="Delimiter">();</span>
     <span class="Identifier">break</span><span class="Delimiter">;</span>
   <span class="Delimiter">}</span>
   long long int src = base_address + <span class="Constant">1</span> + offset_val<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">)</span>*size_of<span class="Delimiter">(</span>element_type<span class="Delimiter">);</span>
-  trace<span class="Delimiter">(</span>Primitive_recipe_depth<span class="Delimiter">,</span> <span class="Constant">&quot;run&quot;</span><span class="Delimiter">)</span> &lt;&lt; <span class="Constant">&quot;address to copy is &quot;</span> &lt;&lt; src &lt;&lt; end<span class="Delimiter">();</span>
-  trace<span class="Delimiter">(</span>Primitive_recipe_depth<span class="Delimiter">,</span> <span class="Constant">&quot;run&quot;</span><span class="Delimiter">)</span> &lt;&lt; <span class="Constant">&quot;its type is &quot;</span> &lt;&lt; Type[element_type<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">)</span>]<span class="Delimiter">.</span>name &lt;&lt; end<span class="Delimiter">();</span>
+  trace<span class="Delimiter">(</span><span class="Constant">9998</span><span class="Delimiter">,</span> <span class="Constant">&quot;run&quot;</span><span class="Delimiter">)</span> &lt;&lt; <span class="Constant">&quot;address to copy is &quot;</span> &lt;&lt; src &lt;&lt; end<span class="Delimiter">();</span>
+  trace<span class="Delimiter">(</span><span class="Constant">9998</span><span class="Delimiter">,</span> <span class="Constant">&quot;run&quot;</span><span class="Delimiter">)</span> &lt;&lt; <span class="Constant">&quot;its type is &quot;</span> &lt;&lt; get<span class="Delimiter">(</span>Type<span class="Delimiter">,</span> element_type<span class="Delimiter">-&gt;</span>value<span class="Delimiter">).</span>name &lt;&lt; end<span class="Delimiter">();</span>
   reagent tmp<span class="Delimiter">;</span>
   tmp<span class="Delimiter">.</span>set_value<span class="Delimiter">(</span>src<span class="Delimiter">);</span>
-  copy<span class="Delimiter">(</span>element_type<span class="Delimiter">.</span>begin<span class="Delimiter">(),</span> element_type<span class="Delimiter">.</span>end<span class="Delimiter">(),</span> inserter<span class="Delimiter">(</span>tmp<span class="Delimiter">.</span>types<span class="Delimiter">,</span> tmp<span class="Delimiter">.</span>types<span class="Delimiter">.</span>begin<span class="Delimiter">()));</span>
+  tmp<span class="Delimiter">.</span>type = new type_tree<span class="Delimiter">(</span>*element_type<span class="Delimiter">);</span>
   products<span class="Delimiter">.</span>push_back<span class="Delimiter">(</span>read_memory<span class="Delimiter">(</span>tmp<span class="Delimiter">));</span>
   <span class="Identifier">break</span><span class="Delimiter">;</span>
 <span class="Delimiter">}</span>
 
 <span class="Delimiter">:(code)</span>
-vector&lt;type_ordinal&gt; array_element<span class="Delimiter">(</span>const vector&lt;type_ordinal&gt;&amp; types<span class="Delimiter">)</span> <span class="Delimiter">{</span>
-  <span class="Identifier">return</span> vector&lt;type_ordinal&gt;<span class="Delimiter">(</span>++types<span class="Delimiter">.</span>begin<span class="Delimiter">(),</span> types<span class="Delimiter">.</span>end<span class="Delimiter">());</span>
+type_tree* array_element<span class="Delimiter">(</span>const type_tree* type<span class="Delimiter">)</span> <span class="Delimiter">{</span>
+  <span class="Identifier">return</span> type<span class="Delimiter">-&gt;</span>right<span class="Delimiter">;</span>
 <span class="Delimiter">}</span>
 
 <span class="Delimiter">:(scenario index_indirect)</span>
@@ -214,13 +238,13 @@ recipe main [
   <span class="Constant">2</span>:number<span class="Special"> &lt;- </span>copy <span class="Constant">14</span>
   <span class="Constant">3</span>:number<span class="Special"> &lt;- </span>copy <span class="Constant">15</span>
   <span class="Constant">4</span>:number<span class="Special"> &lt;- </span>copy <span class="Constant">16</span>
-  <span class="Constant">5</span>:address:array:number<span class="Special"> &lt;- </span>copy <span class="Constant">1</span>
+  <span class="Constant">5</span>:address:array:number<span class="Special"> &lt;- </span>copy <span class="Constant">1</span>/<span class="Special">raw</span>
   <span class="Constant">6</span>:number<span class="Special"> &lt;- </span>index *<span class="Constant">5</span>:address:array:number<span class="Delimiter">,</span> <span class="Constant">1</span>
 ]
 <span class="traceContains">+mem: storing 15 in location 6</span>
 
 <span class="Delimiter">:(scenario index_out_of_bounds)</span>
-<span class="Special">% Hide_warnings = true;</span>
+<span class="Special">% Hide_errors = true;</span>
 recipe main [
   <span class="Constant">1</span>:array:number:<span class="Constant">3</span><span class="Special"> &lt;- </span>create-array
   <span class="Constant">2</span>:number<span class="Special"> &lt;- </span>copy <span class="Constant">14</span>
@@ -232,10 +256,10 @@ recipe main [
   <span class="Constant">8</span>:address:array:point<span class="Special"> &lt;- </span>copy <span class="Constant">1</span>
   index *<span class="Constant">8</span>:address:array:point<span class="Delimiter">,</span> <span class="Constant">4</span>  <span class="Comment"># less than size of array in locations, but larger than its length in elements</span>
 ]
-<span class="traceContains">+warn: main: invalid index 4</span>
+<span class="traceContains">+error: main: invalid index 4</span>
 
 <span class="Delimiter">:(scenario index_out_of_bounds_2)</span>
-<span class="Special">% Hide_warnings = true;</span>
+<span class="Special">% Hide_errors = true;</span>
 recipe main [
   <span class="Constant">1</span>:array:point:<span class="Constant">3</span><span class="Special"> &lt;- </span>create-array
   <span class="Constant">2</span>:number<span class="Special"> &lt;- </span>copy <span class="Constant">14</span>
@@ -244,10 +268,25 @@ recipe main [
   <span class="Constant">5</span>:number<span class="Special"> &lt;- </span>copy <span class="Constant">14</span>
   <span class="Constant">6</span>:number<span class="Special"> &lt;- </span>copy <span class="Constant">15</span>
   <span class="Constant">7</span>:number<span class="Special"> &lt;- </span>copy <span class="Constant">16</span>
-  <span class="Constant">8</span>:address:array:point<span class="Special"> &lt;- </span>copy <span class="Constant">1</span>
+  <span class="Constant">8</span>:address:array:point<span class="Special"> &lt;- </span>copy <span class="Constant">1</span>/<span class="Special">raw</span>
   index *<span class="Constant">8</span>:address:array:point<span class="Delimiter">,</span> -<span class="Constant">1</span>
 ]
-<span class="traceContains">+warn: main: invalid index -1</span>
+<span class="traceContains">+error: main: invalid index -1</span>
+
+<span class="Delimiter">:(scenario index_product_type_mismatch)</span>
+<span class="Special">% Hide_errors = true;</span>
+recipe main [
+  <span class="Constant">1</span>:array:point:<span class="Constant">3</span><span class="Special"> &lt;- </span>create-array
+  <span class="Constant">2</span>:number<span class="Special"> &lt;- </span>copy <span class="Constant">14</span>
+  <span class="Constant">3</span>:number<span class="Special"> &lt;- </span>copy <span class="Constant">15</span>
+  <span class="Constant">4</span>:number<span class="Special"> &lt;- </span>copy <span class="Constant">16</span>
+  <span class="Constant">5</span>:number<span class="Special"> &lt;- </span>copy <span class="Constant">14</span>
+  <span class="Constant">6</span>:number<span class="Special"> &lt;- </span>copy <span class="Constant">15</span>
+  <span class="Constant">7</span>:number<span class="Special"> &lt;- </span>copy <span class="Constant">16</span>
+  <span class="Constant">8</span>:address:array:point<span class="Special"> &lt;- </span>copy <span class="Constant">1</span>/<span class="Special">raw</span>
+  <span class="Constant">9</span>:number<span class="Special"> &lt;- </span>index *<span class="Constant">8</span>:address:array:point<span class="Delimiter">,</span> <span class="Constant">0</span>
+]
+<span class="traceContains">+error: main: 'index' on *8:address:array:point can't be saved in 9:number; type should be point</span>
 
 <span class="SalientComment">//:: To write to elements of containers, you need their address.</span>
 
@@ -257,35 +296,53 @@ recipe main [
   <span class="Constant">2</span>:number<span class="Special"> &lt;- </span>copy <span class="Constant">14</span>
   <span class="Constant">3</span>:number<span class="Special"> &lt;- </span>copy <span class="Constant">15</span>
   <span class="Constant">4</span>:number<span class="Special"> &lt;- </span>copy <span class="Constant">16</span>
-  <span class="Constant">5</span>:number<span class="Special"> &lt;- </span>index-address <span class="Constant">1</span>:array:number<span class="Delimiter">,</span> <span class="Constant">0</span>
+  <span class="Constant">5</span>:address:number<span class="Special"> &lt;- </span>index-address <span class="Constant">1</span>:array:number<span class="Delimiter">,</span> <span class="Constant">0</span>
 ]
 <span class="traceContains">+mem: storing 2 in location 5</span>
 
 <span class="Delimiter">:(before &quot;End Primitive Recipe Declarations&quot;)</span>
 INDEX_ADDRESS<span class="Delimiter">,</span>
 <span class="Delimiter">:(before &quot;End Primitive Recipe Numbers&quot;)</span>
-Recipe_ordinal[<span class="Constant">&quot;index-address&quot;</span>] = INDEX_ADDRESS<span class="Delimiter">;</span>
-<span class="Delimiter">:(before &quot;End Primitive Recipe Implementations&quot;)</span>
+put<span class="Delimiter">(</span>Recipe_ordinal<span class="Delimiter">,</span> <span class="Constant">&quot;index-address&quot;</span><span class="Delimiter">,</span> INDEX_ADDRESS<span class="Delimiter">);</span>
+<span class="Delimiter">:(before &quot;End Primitive Recipe Checks&quot;)</span>
 case INDEX_ADDRESS: <span class="Delimiter">{</span>
-  if <span class="Delimiter">(</span>SIZE<span class="Delimiter">(</span>current_instruction<span class="Delimiter">().</span>ingredients<span class="Delimiter">)</span> != <span class="Constant">2</span><span class="Delimiter">)</span> <span class="Delimiter">{</span>
-    raise &lt;&lt; current_recipe_name<span class="Delimiter">()</span> &lt;&lt; <span class="Constant">&quot;: 'index-address' expects exactly 2 ingredients in '&quot;</span> &lt;&lt; current_instruction<span class="Delimiter">().</span>to_string<span class="Delimiter">()</span> &lt;&lt; <span class="Constant">&quot;'</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span> &lt;&lt; end<span class="Delimiter">();</span>
+  if <span class="Delimiter">(</span>SIZE<span class="Delimiter">(</span>inst<span class="Delimiter">.</span>ingredients<span class="Delimiter">)</span> != <span class="Constant">2</span><span class="Delimiter">)</span> <span class="Delimiter">{</span>
+    raise_error &lt;&lt; maybe<span class="Delimiter">(</span>get<span class="Delimiter">(</span>Recipe<span class="Delimiter">,</span> r<span class="Delimiter">).</span>name<span class="Delimiter">)</span> &lt;&lt; <span class="Constant">&quot;'index-address' expects exactly 2 ingredients in '&quot;</span> &lt;&lt; inst<span class="Delimiter">.</span>to_string<span class="Delimiter">()</span> &lt;&lt; <span class="Constant">&quot;'</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span> &lt;&lt; end<span class="Delimiter">();</span>
     <span class="Identifier">break</span><span class="Delimiter">;</span>
   <span class="Delimiter">}</span>
-  reagent base = canonize<span class="Delimiter">(</span>current_instruction<span class="Delimiter">().</span>ingredients<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">));</span>
+  reagent base = inst<span class="Delimiter">.</span>ingredients<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">);</span>
+  canonize_type<span class="Delimiter">(</span>base<span class="Delimiter">);</span>
   if <span class="Delimiter">(</span>!is_mu_array<span class="Delimiter">(</span>base<span class="Delimiter">))</span> <span class="Delimiter">{</span>
-    raise &lt;&lt; current_recipe_name <span class="Delimiter">()</span> &lt;&lt; <span class="Constant">&quot;: 'index-address' on a non-array &quot;</span> &lt;&lt; base<span class="Delimiter">.</span>original_string &lt;&lt; <span class="cSpecial">'\n'</span> &lt;&lt; end<span class="Delimiter">();</span>
+    raise_error &lt;&lt; maybe<span class="Delimiter">(</span>get<span class="Delimiter">(</span>Recipe<span class="Delimiter">,</span> r<span class="Delimiter">).</span>name<span class="Delimiter">)</span> &lt;&lt; <span class="Constant">&quot;'index-address' on a non-array &quot;</span> &lt;&lt; base<span class="Delimiter">.</span>original_string &lt;&lt; <span class="cSpecial">'\n'</span> &lt;&lt; end<span class="Delimiter">();</span>
     <span class="Identifier">break</span><span class="Delimiter">;</span>
   <span class="Delimiter">}</span>
+  if <span class="Delimiter">(</span>inst<span class="Delimiter">.</span>products<span class="Delimiter">.</span>empty<span class="Delimiter">())</span> <span class="Identifier">break</span><span class="Delimiter">;</span>
+  reagent product = inst<span class="Delimiter">.</span>products<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">);</span>
+  canonize_type<span class="Delimiter">(</span>product<span class="Delimiter">);</span>
+  reagent element<span class="Delimiter">;</span>
+  element<span class="Delimiter">.</span>type = new type_tree<span class="Delimiter">(</span>*array_element<span class="Delimiter">(</span>base<span class="Delimiter">.</span>type<span class="Delimiter">));</span>
+  element<span class="Delimiter">.</span>type = new type_tree<span class="Delimiter">(</span>get<span class="Delimiter">(</span>Type_ordinal<span class="Delimiter">,</span> <span class="Constant">&quot;address&quot;</span><span class="Delimiter">),</span> element<span class="Delimiter">.</span>type<span class="Delimiter">);</span>
+  if <span class="Delimiter">(</span>!types_match<span class="Delimiter">(</span>product<span class="Delimiter">,</span> element<span class="Delimiter">))</span> <span class="Delimiter">{</span>
+    raise_error &lt;&lt; maybe<span class="Delimiter">(</span>get<span class="Delimiter">(</span>Recipe<span class="Delimiter">,</span> r<span class="Delimiter">).</span>name<span class="Delimiter">)</span> &lt;&lt; <span class="Constant">&quot;'index' on &quot;</span> &lt;&lt; base<span class="Delimiter">.</span>original_string &lt;&lt; <span class="Constant">&quot; can't be saved in &quot;</span> &lt;&lt; product<span class="Delimiter">.</span>original_string &lt;&lt; <span class="Constant">&quot;; type should be &quot;</span> &lt;&lt; debug_string<span class="Delimiter">(</span>element<span class="Delimiter">.</span>type<span class="Delimiter">)</span> &lt;&lt; <span class="cSpecial">'\n'</span> &lt;&lt; end<span class="Delimiter">();</span>
+    <span class="Identifier">break</span><span class="Delimiter">;</span>
+  <span class="Delimiter">}</span>
+  <span class="Identifier">break</span><span class="Delimiter">;</span>
+<span class="Delimiter">}</span>
+<span class="Delimiter">:(before &quot;End Primitive Recipe Implementations&quot;)</span>
+case INDEX_ADDRESS: <span class="Delimiter">{</span>
+  reagent base = current_instruction<span class="Delimiter">().</span>ingredients<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">);</span>
+  canonize<span class="Delimiter">(</span>base<span class="Delimiter">);</span>
   long long int base_address = base<span class="Delimiter">.</span>value<span class="Delimiter">;</span>
   if <span class="Delimiter">(</span>base_address == <span class="Constant">0</span><span class="Delimiter">)</span> <span class="Delimiter">{</span>
-    raise &lt;&lt; current_recipe_name<span class="Delimiter">()</span> &lt;&lt; <span class="Constant">&quot;: tried to access location 0 in '&quot;</span> &lt;&lt; current_instruction<span class="Delimiter">().</span>to_string<span class="Delimiter">()</span> &lt;&lt; <span class="Constant">&quot;'</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span> &lt;&lt; end<span class="Delimiter">();</span>
+    raise_error &lt;&lt; maybe<span class="Delimiter">(</span>current_recipe_name<span class="Delimiter">())</span> &lt;&lt; <span class="Constant">&quot;tried to access location 0 in '&quot;</span> &lt;&lt; current_instruction<span class="Delimiter">().</span>to_string<span class="Delimiter">()</span> &lt;&lt; <span class="Constant">&quot;'</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span> &lt;&lt; end<span class="Delimiter">();</span>
     <span class="Identifier">break</span><span class="Delimiter">;</span>
   <span class="Delimiter">}</span>
-  reagent offset = canonize<span class="Delimiter">(</span>current_instruction<span class="Delimiter">().</span>ingredients<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">1</span><span class="Delimiter">));</span>
+  reagent offset = current_instruction<span class="Delimiter">().</span>ingredients<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">1</span><span class="Delimiter">);</span>
+  canonize<span class="Delimiter">(</span>offset<span class="Delimiter">);</span>
   vector&lt;double&gt; offset_val<span class="Delimiter">(</span>read_memory<span class="Delimiter">(</span>offset<span class="Delimiter">));</span>
-  vector&lt;type_ordinal&gt; element_type = array_element<span class="Delimiter">(</span>base<span class="Delimiter">.</span>types<span class="Delimiter">);</span>
-  if <span class="Delimiter">(</span>offset_val<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">)</span> &lt; <span class="Constant">0</span> || offset_val<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">)</span> &gt;= Memory[base_address]<span class="Delimiter">)</span> <span class="Delimiter">{</span>
-    raise &lt;&lt; current_recipe_name<span class="Delimiter">()</span> &lt;&lt; <span class="Constant">&quot;: invalid index &quot;</span> &lt;&lt; offset_val<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">)</span> &lt;&lt; <span class="cSpecial">'\n'</span> &lt;&lt; end<span class="Delimiter">();</span>
+  type_tree* element_type = array_element<span class="Delimiter">(</span>base<span class="Delimiter">.</span>type<span class="Delimiter">);</span>
+  if <span class="Delimiter">(</span>offset_val<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">)</span> &lt; <span class="Constant">0</span> || offset_val<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">)</span> &gt;= get_or_insert<span class="Delimiter">(</span>Memory<span class="Delimiter">,</span> base_address<span class="Delimiter">))</span> <span class="Delimiter">{</span>
+    raise_error &lt;&lt; maybe<span class="Delimiter">(</span>current_recipe_name<span class="Delimiter">())</span> &lt;&lt; <span class="Constant">&quot;invalid index &quot;</span> &lt;&lt; no_scientific<span class="Delimiter">(</span>offset_val<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">))</span> &lt;&lt; <span class="cSpecial">'\n'</span> &lt;&lt; end<span class="Delimiter">();</span>
     <span class="Identifier">break</span><span class="Delimiter">;</span>
   <span class="Delimiter">}</span>
   long long int result = base_address + <span class="Constant">1</span> + offset_val<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">)</span>*size_of<span class="Delimiter">(</span>element_type<span class="Delimiter">);</span>
@@ -295,7 +352,7 @@ case INDEX_ADDRESS: <span class="Delimiter">{</span>
 <span class="Delimiter">}</span>
 
 <span class="Delimiter">:(scenario index_address_out_of_bounds)</span>
-<span class="Special">% Hide_warnings = true;</span>
+<span class="Special">% Hide_errors = true;</span>
 recipe main [
   <span class="Constant">1</span>:array:point:<span class="Constant">3</span><span class="Special"> &lt;- </span>create-array
   <span class="Constant">2</span>:number<span class="Special"> &lt;- </span>copy <span class="Constant">14</span>
@@ -307,10 +364,10 @@ recipe main [
   <span class="Constant">8</span>:address:array:point<span class="Special"> &lt;- </span>copy <span class="Constant">1</span>  <span class="Comment"># unsafe</span>
   index-address *<span class="Constant">8</span>:address:array:point<span class="Delimiter">,</span> <span class="Constant">4</span>  <span class="Comment"># less than size of array in locations, but larger than its length in elements</span>
 ]
-<span class="traceContains">+warn: main: invalid index 4</span>
+<span class="traceContains">+error: main: invalid index 4</span>
 
 <span class="Delimiter">:(scenario index_address_out_of_bounds_2)</span>
-<span class="Special">% Hide_warnings = true;</span>
+<span class="Special">% Hide_errors = true;</span>
 recipe main [
   <span class="Constant">1</span>:array:point:<span class="Constant">3</span><span class="Special"> &lt;- </span>create-array
   <span class="Constant">2</span>:number<span class="Special"> &lt;- </span>copy <span class="Constant">14</span>
@@ -319,10 +376,25 @@ recipe main [
   <span class="Constant">5</span>:number<span class="Special"> &lt;- </span>copy <span class="Constant">14</span>
   <span class="Constant">6</span>:number<span class="Special"> &lt;- </span>copy <span class="Constant">15</span>
   <span class="Constant">7</span>:number<span class="Special"> &lt;- </span>copy <span class="Constant">16</span>
-  <span class="Constant">8</span>:address:array:point<span class="Special"> &lt;- </span>copy <span class="Constant">1</span>  <span class="Comment"># unsafe</span>
+  <span class="Constant">8</span>:address:array:point<span class="Special"> &lt;- </span>copy <span class="Constant">1</span>/<span class="Special">raw</span>
   index-address *<span class="Constant">8</span>:address:array:point<span class="Delimiter">,</span> -<span class="Constant">1</span>
 ]
-<span class="traceContains">+warn: main: invalid index -1</span>
+<span class="traceContains">+error: main: invalid index -1</span>
+
+<span class="Delimiter">:(scenario index_address_product_type_mismatch)</span>
+<span class="Special">% Hide_errors = true;</span>
+recipe main [
+  <span class="Constant">1</span>:array:point:<span class="Constant">3</span><span class="Special"> &lt;- </span>create-array
+  <span class="Constant">2</span>:number<span class="Special"> &lt;- </span>copy <span class="Constant">14</span>
+  <span class="Constant">3</span>:number<span class="Special"> &lt;- </span>copy <span class="Constant">15</span>
+  <span class="Constant">4</span>:number<span class="Special"> &lt;- </span>copy <span class="Constant">16</span>
+  <span class="Constant">5</span>:number<span class="Special"> &lt;- </span>copy <span class="Constant">14</span>
+  <span class="Constant">6</span>:number<span class="Special"> &lt;- </span>copy <span class="Constant">15</span>
+  <span class="Constant">7</span>:number<span class="Special"> &lt;- </span>copy <span class="Constant">16</span>
+  <span class="Constant">8</span>:address:array:point<span class="Special"> &lt;- </span>copy <span class="Constant">1</span>/<span class="Special">raw</span>
+  <span class="Constant">9</span>:address:number<span class="Special"> &lt;- </span>index-address *<span class="Constant">8</span>:address:array:point<span class="Delimiter">,</span> <span class="Constant">0</span>
+]
+<span class="traceContains">+error: main: 'index' on *8:address:array:point can't be saved in 9:address:number; type should be &lt;address : &lt;point : &lt;&gt;&gt;&gt;</span>
 
 <span class="SalientComment">//:: compute the length of an array</span>
 
@@ -339,24 +411,31 @@ recipe main [
 <span class="Delimiter">:(before &quot;End Primitive Recipe Declarations&quot;)</span>
 LENGTH<span class="Delimiter">,</span>
 <span class="Delimiter">:(before &quot;End Primitive Recipe Numbers&quot;)</span>
-Recipe_ordinal[<span class="Constant">&quot;length&quot;</span>] = LENGTH<span class="Delimiter">;</span>
-<span class="Delimiter">:(before &quot;End Primitive Recipe Implementations&quot;)</span>
+put<span class="Delimiter">(</span>Recipe_ordinal<span class="Delimiter">,</span> <span class="Constant">&quot;length&quot;</span><span class="Delimiter">,</span> LENGTH<span class="Delimiter">);</span>
+<span class="Delimiter">:(before &quot;End Primitive Recipe Checks&quot;)</span>
 case LENGTH: <span class="Delimiter">{</span>
-  if <span class="Delimiter">(</span>SIZE<span class="Delimiter">(</span>current_instruction<span class="Delimiter">().</span>ingredients<span class="Delimiter">)</span> != <span class="Constant">1</span><span class="Delimiter">)</span> <span class="Delimiter">{</span>
-    raise &lt;&lt; current_recipe_name<span class="Delimiter">()</span> &lt;&lt; <span class="Constant">&quot;: 'length' expects exactly 2 ingredients in '&quot;</span> &lt;&lt; current_instruction<span class="Delimiter">().</span>to_string<span class="Delimiter">()</span> &lt;&lt; <span class="Constant">&quot;'</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span> &lt;&lt; end<span class="Delimiter">();</span>
+  if <span class="Delimiter">(</span>SIZE<span class="Delimiter">(</span>inst<span class="Delimiter">.</span>ingredients<span class="Delimiter">)</span> != <span class="Constant">1</span><span class="Delimiter">)</span> <span class="Delimiter">{</span>
+    raise_error &lt;&lt; maybe<span class="Delimiter">(</span>get<span class="Delimiter">(</span>Recipe<span class="Delimiter">,</span> r<span class="Delimiter">).</span>name<span class="Delimiter">)</span> &lt;&lt; <span class="Constant">&quot;'length' expects exactly 2 ingredients in '&quot;</span> &lt;&lt; inst<span class="Delimiter">.</span>to_string<span class="Delimiter">()</span> &lt;&lt; <span class="Constant">&quot;'</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span> &lt;&lt; end<span class="Delimiter">();</span>
     <span class="Identifier">break</span><span class="Delimiter">;</span>
   <span class="Delimiter">}</span>
-  reagent x = canonize<span class="Delimiter">(</span>current_instruction<span class="Delimiter">().</span>ingredients<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">));</span>
+  reagent x = inst<span class="Delimiter">.</span>ingredients<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">);</span>
+  canonize_type<span class="Delimiter">(</span>x<span class="Delimiter">);</span>
   if <span class="Delimiter">(</span>!is_mu_array<span class="Delimiter">(</span>x<span class="Delimiter">))</span> <span class="Delimiter">{</span>
-    raise &lt;&lt; <span class="Constant">&quot;tried to calculate length of non-array &quot;</span> &lt;&lt; x<span class="Delimiter">.</span>original_string &lt;&lt; <span class="cSpecial">'\n'</span> &lt;&lt; end<span class="Delimiter">();</span>
+    raise_error &lt;&lt; <span class="Constant">&quot;tried to calculate length of non-array &quot;</span> &lt;&lt; x<span class="Delimiter">.</span>original_string &lt;&lt; <span class="cSpecial">'\n'</span> &lt;&lt; end<span class="Delimiter">();</span>
     <span class="Identifier">break</span><span class="Delimiter">;</span>
   <span class="Delimiter">}</span>
+  <span class="Identifier">break</span><span class="Delimiter">;</span>
+<span class="Delimiter">}</span>
+<span class="Delimiter">:(before &quot;End Primitive Recipe Implementations&quot;)</span>
+case LENGTH: <span class="Delimiter">{</span>
+  reagent x = current_instruction<span class="Delimiter">().</span>ingredients<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">);</span>
+  canonize<span class="Delimiter">(</span>x<span class="Delimiter">);</span>
   if <span class="Delimiter">(</span>x<span class="Delimiter">.</span>value == <span class="Constant">0</span><span class="Delimiter">)</span> <span class="Delimiter">{</span>
-    raise &lt;&lt; current_recipe_name<span class="Delimiter">()</span> &lt;&lt; <span class="Constant">&quot;: tried to access location 0 in '&quot;</span> &lt;&lt; current_instruction<span class="Delimiter">().</span>to_string<span class="Delimiter">()</span> &lt;&lt; <span class="Constant">&quot;'</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span> &lt;&lt; end<span class="Delimiter">();</span>
+    raise_error &lt;&lt; maybe<span class="Delimiter">(</span>current_recipe_name<span class="Delimiter">())</span> &lt;&lt; <span class="Constant">&quot;tried to access location 0 in '&quot;</span> &lt;&lt; current_instruction<span class="Delimiter">().</span>to_string<span class="Delimiter">()</span> &lt;&lt; <span class="Constant">&quot;'</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span> &lt;&lt; end<span class="Delimiter">();</span>
     <span class="Identifier">break</span><span class="Delimiter">;</span>
   <span class="Delimiter">}</span>
   products<span class="Delimiter">.</span>resize<span class="Delimiter">(</span><span class="Constant">1</span><span class="Delimiter">);</span>
-  products<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">).</span>push_back<span class="Delimiter">(</span>Memory[x<span class="Delimiter">.</span>value]<span class="Delimiter">);</span>
+  products<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">).</span>push_back<span class="Delimiter">(</span>get_or_insert<span class="Delimiter">(</span>Memory<span class="Delimiter">,</span> x<span class="Delimiter">.</span>value<span class="Delimiter">));</span>
   <span class="Identifier">break</span><span class="Delimiter">;</span>
 <span class="Delimiter">}</span>