<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html>
<head>
<meta http-equiv="content-type" content="text/html; charset=UTF-8">
<title>Mu - 033exclusive_container.cc</title>
<meta name="Generator" content="Vim/7.3">
<meta name="plugin-version" content="vim7.3_v6">
<meta name="syntax" content="cpp">
<meta name="settings" content="use_css">
<style type="text/css">
<!--
pre { font-family: monospace; color: #eeeeee; background-color: #080808; }
body { font-family: monospace; color: #eeeeee; background-color: #080808; }
.cSpecial { color: #008000; }
.SalientComment { color: #00ffff; }
.Identifier { color: #804000; }
.traceContains { color: #008000; }
.Normal { color: #eeeeee; background-color: #080808; }
.Special { color: #ff6060; }
.Constant { color: #00a0a0; }
.Delimiter { color: #a04060; }
.Comment { color: #9090ff; }
-->
</style>
</head>
<body>
<pre>
<span class="Comment">//: Exclusive containers contain exactly one of a fixed number of 'variants'</span>
<span class="Comment">//: of different types.</span>
<span class="Comment">//:</span>
<span class="Comment">//: They also implicitly contain a tag describing precisely which variant is</span>
<span class="Comment">//: currently stored in them.</span>
<span class="Delimiter">:(before "End Mu Types Initialization")</span>
<span class="Comment">//: We'll use this container as a running example, with two number elements.</span>
<span class="Delimiter">{</span>
type_ordinal tmp = put<span class="Delimiter">(</span>Type_ordinal<span class="Delimiter">,</span> <span class="Constant">"number-or-point"</span><span class="Delimiter">,</span> Next_type_ordinal++<span class="Delimiter">);</span>
get_or_insert<span class="Delimiter">(</span>Type<span class="Delimiter">,</span> tmp<span class="Delimiter">).</span>size = <span class="Constant">2</span><span class="Delimiter">;</span>
get<span class="Delimiter">(</span>Type<span class="Delimiter">,</span> tmp<span class="Delimiter">).</span>kind = EXCLUSIVE_CONTAINER<span class="Delimiter">;</span>
get<span class="Delimiter">(</span>Type<span class="Delimiter">,</span> tmp<span class="Delimiter">).</span>name = <span class="Constant">"number-or-point"</span><span class="Delimiter">;</span>
get<span class="Delimiter">(</span>Type<span class="Delimiter">,</span> tmp<span class="Delimiter">).</span>elements<span class="Delimiter">.</span>push_back<span class="Delimiter">(</span>reagent<span class="Delimiter">(</span><span class="Constant">"i:number"</span><span class="Delimiter">));</span>
get<span class="Delimiter">(</span>Type<span class="Delimiter">,</span> tmp<span class="Delimiter">).</span>elements<span class="Delimiter">.</span>push_back<span class="Delimiter">(</span>reagent<span class="Delimiter">(</span><span class="Constant">"p:point"</span><span class="Delimiter">));</span>
<span class="Delimiter">}</span>
<span class="Comment">//: Tests in this layer often explicitly setup memory before reading it as an</span>
<span class="Comment">//: array. Don't do this in general. I'm tagging exceptions with /raw to</span>
<span class="Comment">//: avoid errors.</span>
<span class="Delimiter">:(scenario copy_exclusive_container)</span>
<span class="Comment"># Copying exclusive containers copies all their contents and an extra location for the tag.</span>
def main [
<span class="Constant">1</span>:number<span class="Special"> <- </span>copy <span class="Constant">1</span> <span class="Comment"># 'point' variant</span>
<span class="Constant">2</span>:number<span class="Special"> <- </span>copy <span class="Constant">34</span>
<span class="Constant">3</span>:number<span class="Special"> <- </span>copy <span class="Constant">35</span>
<span class="Constant">4</span>:number-<span class="Normal">or</span>-point<span class="Special"> <- </span>copy <span class="Constant">1</span>:number-<span class="Normal">or</span>-point/unsafe
]
<span class="traceContains">+mem: storing 1 in location 4</span>
<span class="traceContains">+mem: storing 34 in location 5</span>
<span class="traceContains">+mem: storing 35 in location 6</span>
<span class="Delimiter">:(before "End size_of(type) Cases")</span>
<span class="Normal">if</span> <span class="Delimiter">(</span>t<span class="Delimiter">.</span>kind == EXCLUSIVE_CONTAINER<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span class="Comment">// size of an exclusive container is the size of its largest variant</span>
<span class="Comment">// (So like containers, it can't contain arrays.)</span>
<span class="Normal">long</span> <span class="Normal">long</span> <span class="Normal">int</span> result = <span class="Constant">0</span><span class="Delimiter">;</span>
<span class="Normal">for</span> <span class="Delimiter">(</span><span class="Normal">long</span> <span class="Normal">long</span> <span class="Normal">int</span> i = <span class="Constant">0</span><span class="Delimiter">;</span> i < t<span class="Delimiter">.</span>size<span class="Delimiter">;</span> ++i<span class="Delimiter">)</span> <span class="Delimiter">{</span>
reagent tmp<span class="Delimiter">;</span>
tmp<span class="Delimiter">.</span>type = <span class="Normal">new</span> type_tree<span class="Delimiter">(</span>*type<span class="Delimiter">);</span>
<span class="Normal">long</span> <span class="Normal">long</span> <span class="Normal">int</span> size = size_of<span class="Delimiter">(</span>variant_type<span class="Delimiter">(</span>tmp<span class="Delimiter">,</span> i<span class="Delimiter">));</span>
<span class="Normal">if</span> <span class="Delimiter">(</span>size > result<span class="Delimiter">)</span> result = size<span class="Delimiter">;</span>
<span class="Delimiter">}</span>
<span class="Comment">// ...+1 for its tag.</span>
<span class="Identifier">return</span> result+<span class="Constant">1</span><span class="Delimiter">;</span>
<span class="Delimiter">}</span>
<span class="SalientComment">//:: To access variants of an exclusive container, use 'maybe-convert'.</span>
<span class="Comment">//: It always returns an address (so that you can modify it) or null (to</span>
<span class="Comment">//: signal that the conversion failed (because the container contains a</span>
<span class="Comment">//: different variant).</span>
<span class="Comment">//: 'maybe-convert' requires a literal in ingredient 1. We'll use a synonym</span>
<span class="Comment">//: called 'variant'.</span>
<span class="Delimiter">:(before "End Mu Types Initialization")</span>
put<span class="Delimiter">(</span>Type_ordinal<span class="Delimiter">,</span> <span class="Constant">"variant"</span><span class="Delimiter">,</span> <span class="Constant">0</span><span class="Delimiter">);</span>
<span class="Delimiter">:(scenario maybe_convert)</span>
def main [
<span class="Constant">12</span>:number<span class="Special"> <- </span>copy <span class="Constant">1</span>
<span class="Constant">13</span>:number<span class="Special"> <- </span>copy <span class="Constant">35</span>
<span class="Constant">14</span>:number<span class="Special"> <- </span>copy <span class="Constant">36</span>
<span class="Constant">20</span>:address:point<span class="Special"> <- </span>maybe-convert <span class="Constant">12</span>:number-<span class="Normal">or</span>-point/unsafe<span class="Delimiter">,</span> <span class="Constant">1</span>:variant
]
<span class="traceContains">+mem: storing 13 in location 20</span>
<span class="Delimiter">:(scenario maybe_convert_fail)</span>
def main [
<span class="Constant">12</span>:number<span class="Special"> <- </span>copy <span class="Constant">1</span>
<span class="Constant">13</span>:number<span class="Special"> <- </span>copy <span class="Constant">35</span>
<span class="Constant">14</span>:number<span class="Special"> <- </span>copy <span class="Constant">36</span>
<span class="Constant">20</span>:address:number<span class="Special"> <- </span>maybe-convert <span class="Constant">12</span>:number-<span class="Normal">or</span>-point/unsafe<span class="Delimiter">,</span> <span class="Constant">0</span>:variant
]
<span class="traceContains">+mem: storing 0 in location 20</span>
<span class="Delimiter">:(before "End Primitive Recipe Declarations")</span>
MAYBE_CONVERT<span class="Delimiter">,</span>
<span class="Delimiter">:(before "End Primitive Recipe Numbers")</span>
put<span class="Delimiter">(</span>Recipe_ordinal<span class="Delimiter">,</span> <span class="Constant">"maybe-convert"</span><span class="Delimiter">,</span> MAYBE_CONVERT<span class="Delimiter">);</span>
<span class="Delimiter">:(before "End Primitive Recipe Checks")</span>
<span class="Normal">case</span> MAYBE_CONVERT: <span class="Delimiter">{</span>
<span class="Normal">const</span> recipe& caller = get<span class="Delimiter">(</span>Recipe<span class="Delimiter">,</span> r<span class="Delimiter">);</span>
<span class="Normal">if</span> <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 << maybe<span class="Delimiter">(</span>caller<span class="Delimiter">.</span>name<span class="Delimiter">)</span> << <span class="Constant">"'maybe-convert' expects exactly 2 ingredients in '"</span> << to_string<span class="Delimiter">(</span>inst<span class="Delimiter">)</span> << <span class="Constant">"'</span><span class="cSpecial">\n</span><span class="Constant">"</span> << end<span class="Delimiter">();</span>
<span class="Identifier">break</span><span class="Delimiter">;</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>
<span class="Normal">if</span> <span class="Delimiter">(</span>!base<span class="Delimiter">.</span>type || !base<span class="Delimiter">.</span>type<span class="Delimiter">-></span>value || get<span class="Delimiter">(</span>Type<span class="Delimiter">,</span> base<span class="Delimiter">.</span>type<span class="Delimiter">-></span>value<span class="Delimiter">).</span>kind != EXCLUSIVE_CONTAINER<span class="Delimiter">)</span> <span class="Delimiter">{</span>
raise << maybe<span class="Delimiter">(</span>caller<span class="Delimiter">.</span>name<span class="Delimiter">)</span> << <span class="Constant">"first ingredient of 'maybe-convert' should be an exclusive-container, but got "</span> << base<span class="Delimiter">.</span>original_string << <span class="cSpecial">'\n'</span> << end<span class="Delimiter">();</span>
<span class="Identifier">break</span><span class="Delimiter">;</span>
<span class="Delimiter">}</span>
<span class="Normal">if</span> <span class="Delimiter">(</span>!is_literal<span class="Delimiter">(</span>inst<span class="Delimiter">.</span>ingredients<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">1</span><span class="Delimiter">)))</span> <span class="Delimiter">{</span>
raise << maybe<span class="Delimiter">(</span>caller<span class="Delimiter">.</span>name<span class="Delimiter">)</span> << <span class="Constant">"second ingredient of 'maybe-convert' should have type 'variant', but got "</span> << inst<span class="Delimiter">.</span>ingredients<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">1</span><span class="Delimiter">).</span>original_string << <span class="cSpecial">'\n'</span> << end<span class="Delimiter">();</span>
<span class="Identifier">break</span><span class="Delimiter">;</span>
<span class="Delimiter">}</span>
<span class="Normal">if</span> <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>
<span class="Normal">if</span> <span class="Delimiter">(</span>!canonize_type<span class="Delimiter">(</span>product<span class="Delimiter">))</span> <span class="Identifier">break</span><span class="Delimiter">;</span>
reagent& offset = inst<span class="Delimiter">.</span>ingredients<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">1</span><span class="Delimiter">);</span>
populate_value<span class="Delimiter">(</span>offset<span class="Delimiter">);</span>
<span class="Normal">if</span> <span class="Delimiter">(</span>offset<span class="Delimiter">.</span>value >= SIZE<span class="Delimiter">(</span>get<span class="Delimiter">(</span>Type<span class="Delimiter">,</span> base<span class="Delimiter">.</span>type<span class="Delimiter">-></span>value<span class="Delimiter">).</span>elements<span class="Delimiter">))</span> <span class="Delimiter">{</span>
raise << maybe<span class="Delimiter">(</span>caller<span class="Delimiter">.</span>name<span class="Delimiter">)</span> << <span class="Constant">"invalid tag "</span> << offset<span class="Delimiter">.</span>value << <span class="Constant">" in '"</span> << to_string<span class="Delimiter">(</span>inst<span class="Delimiter">)</span> << <span class="cSpecial">'\n'</span> << end<span class="Delimiter">();</span>
<span class="Identifier">break</span><span class="Delimiter">;</span>
<span class="Delimiter">}</span>
reagent variant = variant_type<span class="Delimiter">(</span>base<span class="Delimiter">,</span> offset<span class="Delimiter">.</span>value<span class="Delimiter">);</span>
variant<span class="Delimiter">.</span>type = <span class="Normal">new</span> type_tree<span class="Delimiter">(</span><span class="Constant">"address"</span><span class="Delimiter">,</span> get<span class="Delimiter">(</span>Type_ordinal<span class="Delimiter">,</span> <span class="Constant">"address"</span><span class="Delimiter">),</span> variant<span class="Delimiter">.</span>type<span class="Delimiter">);</span>
<span class="Normal">if</span> <span class="Delimiter">(</span>!types_coercible<span class="Delimiter">(</span>product<span class="Delimiter">,</span> variant<span class="Delimiter">))</span> <span class="Delimiter">{</span>
raise << maybe<span class="Delimiter">(</span>caller<span class="Delimiter">.</span>name<span class="Delimiter">)</span> << <span class="Constant">"'maybe-convert "</span> << base<span class="Delimiter">.</span>original_string << <span class="Constant">", "</span> << inst<span class="Delimiter">.</span>ingredients<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">1</span><span class="Delimiter">).</span>original_string << <span class="Constant">"' should write to "</span> << to_string<span class="Delimiter">(</span>variant<span class="Delimiter">.</span>type<span class="Delimiter">)</span> << <span class="Constant">" but "</span> << product<span class="Delimiter">.</span>name << <span class="Constant">" has type "</span> << to_string<span class="Delimiter">(</span>product<span class="Delimiter">.</span>type<span class="Delimiter">)</span> << <span class="cSpecial">'\n'</span> << 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 "End Primitive Recipe Implementations")</span>
<span class="Normal">case</span> MAYBE_CONVERT: <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>
<span class="Normal">long</span> <span class="Normal">long</span> <span class="Normal">int</span> base_address = base<span class="Delimiter">.</span>value<span class="Delimiter">;</span>
<span class="Normal">if</span> <span class="Delimiter">(</span>base_address == <span class="Constant">0</span><span class="Delimiter">)</span> <span class="Delimiter">{</span>
raise << maybe<span class="Delimiter">(</span>current_recipe_name<span class="Delimiter">())</span> << <span class="Constant">"tried to access location 0 in '"</span> << to_string<span class="Delimiter">(</span>current_instruction<span class="Delimiter">())</span> << <span class="Constant">"'</span><span class="cSpecial">\n</span><span class="Constant">"</span> << end<span class="Delimiter">();</span>
<span class="Identifier">break</span><span class="Delimiter">;</span>
<span class="Delimiter">}</span>
<span class="Normal">long</span> <span class="Normal">long</span> <span class="Normal">int</span> tag = 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>value<span class="Delimiter">;</span>
<span class="Normal">long</span> <span class="Normal">long</span> <span class="Normal">int</span> result<span class="Delimiter">;</span>
<span class="Normal">if</span> <span class="Delimiter">(</span>tag == <span class="Normal">static_cast</span><<span class="Normal">long</span> <span class="Normal">long</span> <span class="Normal">int</span>><span class="Delimiter">(</span>get_or_insert<span class="Delimiter">(</span>Memory<span class="Delimiter">,</span> base_address<span class="Delimiter">)))</span> <span class="Delimiter">{</span>
result = base_address+<span class="Constant">1</span><span class="Delimiter">;</span>
<span class="Delimiter">}</span>
<span class="Normal">else</span> <span class="Delimiter">{</span>
result = <span class="Constant">0</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>result<span class="Delimiter">);</span>
<span class="Identifier">break</span><span class="Delimiter">;</span>
<span class="Delimiter">}</span>
<span class="Delimiter">:(code)</span>
<span class="Normal">const</span> reagent variant_type<span class="Delimiter">(</span><span class="Normal">const</span> reagent& canonized_base<span class="Delimiter">,</span> <span class="Normal">long</span> <span class="Normal">long</span> <span class="Normal">int</span> tag<span class="Delimiter">)</span> <span class="Delimiter">{</span>
assert<span class="Delimiter">(</span>tag >= <span class="Constant">0</span><span class="Delimiter">);</span>
assert<span class="Delimiter">(</span>contains_key<span class="Delimiter">(</span>Type<span class="Delimiter">,</span> canonized_base<span class="Delimiter">.</span>type<span class="Delimiter">-></span>value<span class="Delimiter">));</span>
assert<span class="Delimiter">(</span>!get<span class="Delimiter">(</span>Type<span class="Delimiter">,</span> canonized_base<span class="Delimiter">.</span>type<span class="Delimiter">-></span>value<span class="Delimiter">).</span>name<span class="Delimiter">.</span>empty<span class="Delimiter">());</span>
<span class="Normal">const</span> type_info& info = get<span class="Delimiter">(</span>Type<span class="Delimiter">,</span> canonized_base<span class="Delimiter">.</span>type<span class="Delimiter">-></span>value<span class="Delimiter">);</span>
assert<span class="Delimiter">(</span>info<span class="Delimiter">.</span>kind == EXCLUSIVE_CONTAINER<span class="Delimiter">);</span>
reagent element = info<span class="Delimiter">.</span>elements<span class="Delimiter">.</span>at<span class="Delimiter">(</span>tag<span class="Delimiter">);</span>
<span class="Comment">// End variant_type Special-cases</span>
<span class="Identifier">return</span> element<span class="Delimiter">;</span>
<span class="Delimiter">}</span>
<span class="Delimiter">:(scenario maybe_convert_product_type_mismatch)</span>
<span class="Special">% Hide_errors = true;</span>
def main [
<span class="Constant">12</span>:number<span class="Special"> <- </span>copy <span class="Constant">1</span>
<span class="Constant">13</span>:number<span class="Special"> <- </span>copy <span class="Constant">35</span>
<span class="Constant">14</span>:number<span class="Special"> <- </span>copy <span class="Constant">36</span>
<span class="Constant">20</span>:address:number<span class="Special"> <- </span>maybe-convert <span class="Constant">12</span>:number-<span class="Normal">or</span>-point/unsafe<span class="Delimiter">,</span> <span class="Constant">1</span>:variant
]
<span class="traceContains">+error: main: 'maybe-convert 12:number-or-point/unsafe, 1:variant' should write to (address point) but 20 has type (address number)</span>
<span class="SalientComment">//:: Allow exclusive containers to be defined in mu code.</span>
<span class="Delimiter">:(scenario exclusive_container)</span>
exclusive-container foo [
x:number
y:number
]
<span class="traceContains">+parse: --- defining exclusive-container foo</span>
<span class="traceContains">+parse: element: x: "number"</span>
<span class="traceContains">+parse: element: y: "number"</span>
<span class="Delimiter">:(before "End Command Handlers")</span>
<span class="Normal">else</span> <span class="Normal">if</span> <span class="Delimiter">(</span>command == <span class="Constant">"exclusive-container"</span><span class="Delimiter">)</span> <span class="Delimiter">{</span>
insert_container<span class="Delimiter">(</span>command<span class="Delimiter">,</span> EXCLUSIVE_CONTAINER<span class="Delimiter">,</span> in<span class="Delimiter">);</span>
<span class="Delimiter">}</span>
<span class="Comment">//: arrays are disallowed inside exclusive containers unless their length is</span>
<span class="Comment">//: fixed in advance</span>
<span class="Delimiter">:(scenario exclusive_container_contains_array)</span>
exclusive-container foo [
x:array:number:<span class="Constant">3</span>
]
$error: <span class="Constant">0</span>
<span class="Delimiter">:(scenario exclusive_container_disallows_dynamic_array_element)</span>
<span class="Special">% Hide_errors = true;</span>
exclusive-container foo [
x:array:number
]
<span class="traceContains">+error: container 'foo' cannot determine size of element x</span>
<span class="SalientComment">//:: To construct exclusive containers out of variant types, use 'merge'.</span>
<span class="Delimiter">:(scenario lift_to_exclusive_container)</span>
exclusive-container foo [
x:number
y:number
]
def main [
<span class="Constant">1</span>:number<span class="Special"> <- </span>copy <span class="Constant">34</span>
<span class="Constant">2</span>:foo<span class="Special"> <- </span>merge <span class="Constant">0</span>/x<span class="Delimiter">,</span> <span class="Constant">1</span>:number <span class="Comment"># tag must be a literal when merging exclusive containers</span>
<span class="Constant">4</span>:foo<span class="Special"> <- </span>merge <span class="Constant">1</span>/y<span class="Delimiter">,</span> <span class="Constant">1</span>:number
]
<span class="traceContains">+mem: storing 0 in location 2</span>
<span class="traceContains">+mem: storing 34 in location 3</span>
<span class="traceContains">+mem: storing 1 in location 4</span>
<span class="traceContains">+mem: storing 34 in location 5</span>
<span class="Comment">//: type-checking for 'merge' on exclusive containers</span>
<span class="Delimiter">:(scenario merge_handles_exclusive_container)</span>
exclusive-container foo [
x:number
y:bar
]
container bar [
z:number
]
def main [
<span class="Constant">1</span>:foo<span class="Special"> <- </span>merge <span class="Constant">0</span>/x<span class="Delimiter">,</span> <span class="Constant">34</span>
]
<span class="traceContains">+mem: storing 0 in location 1</span>
<span class="traceContains">+mem: storing 34 in location 2</span>
$error: <span class="Constant">0</span>
<span class="Delimiter">:(scenario merge_requires_literal_tag_for_exclusive_container)</span>
<span class="Special">% Hide_errors = true;</span>
exclusive-container foo [
x:number
y:bar
]
container bar [
z:number
]
def main [
local-scope
<span class="Constant">1</span>:number<span class="Special"> <- </span>copy <span class="Constant">0</span>
<span class="Constant">2</span>:foo<span class="Special"> <- </span>merge <span class="Constant">1</span>:number<span class="Delimiter">,</span> <span class="Constant">34</span>
]
<span class="traceContains">+error: main: ingredient 0 of 'merge' should be a literal, for the tag of exclusive-container foo</span>
<span class="Delimiter">:(before "End valid_merge Cases")</span>
<span class="Normal">case</span> EXCLUSIVE_CONTAINER: <span class="Delimiter">{</span>
assert<span class="Delimiter">(</span>state<span class="Delimiter">.</span>data<span class="Delimiter">.</span>top<span class="Delimiter">().</span>container_element_index == <span class="Constant">0</span><span class="Delimiter">);</span>
trace<span class="Delimiter">(</span><span class="Constant">9999</span><span class="Delimiter">,</span> <span class="Constant">"transform"</span><span class="Delimiter">)</span> << <span class="Constant">"checking exclusive container "</span> << to_string<span class="Delimiter">(</span>container<span class="Delimiter">)</span> << <span class="Constant">" vs ingredient "</span> << ingredient_index << end<span class="Delimiter">();</span>
<span class="Normal">if</span> <span class="Delimiter">(</span>!is_literal<span class="Delimiter">(</span>ingredients<span class="Delimiter">.</span>at<span class="Delimiter">(</span>ingredient_index<span class="Delimiter">)))</span> <span class="Delimiter">{</span>
raise << maybe<span class="Delimiter">(</span>caller<span class="Delimiter">.</span>name<span class="Delimiter">)</span> << <span class="Constant">"ingredient "</span> << ingredient_index << <span class="Constant">" of 'merge' should be a literal, for the tag of exclusive-container "</span> << container_info<span class="Delimiter">.</span>name << <span class="cSpecial">'\n'</span> << end<span class="Delimiter">();</span>
<span class="Identifier">return</span><span class="Delimiter">;</span>
<span class="Delimiter">}</span>
reagent ingredient = ingredients<span class="Delimiter">.</span>at<span class="Delimiter">(</span>ingredient_index<span class="Delimiter">);</span> <span class="Comment">// unnecessary copy just to keep this function from modifying caller</span>
populate_value<span class="Delimiter">(</span>ingredient<span class="Delimiter">);</span>
<span class="Normal">if</span> <span class="Delimiter">(</span>ingredient<span class="Delimiter">.</span>value >= SIZE<span class="Delimiter">(</span>container_info<span class="Delimiter">.</span>elements<span class="Delimiter">))</span> <span class="Delimiter">{</span>
raise << maybe<span class="Delimiter">(</span>caller<span class="Delimiter">.</span>name<span class="Delimiter">)</span> << <span class="Constant">"invalid tag at "</span> << ingredient_index << <span class="Constant">" for "</span> << container_info<span class="Delimiter">.</span>name << <span class="Constant">" in '"</span> << to_string<span class="Delimiter">(</span>inst<span class="Delimiter">)</span> << <span class="cSpecial">'\n'</span> << end<span class="Delimiter">();</span>
<span class="Identifier">return</span><span class="Delimiter">;</span>
<span class="Delimiter">}</span>
reagent variant = variant_type<span class="Delimiter">(</span>container<span class="Delimiter">,</span> ingredient<span class="Delimiter">.</span>value<span class="Delimiter">);</span>
trace<span class="Delimiter">(</span><span class="Constant">9999</span><span class="Delimiter">,</span> <span class="Constant">"transform"</span><span class="Delimiter">)</span> << <span class="Constant">"tag: "</span> << ingredient<span class="Delimiter">.</span>value << end<span class="Delimiter">();</span>
<span class="Comment">// replace union with its variant</span>
state<span class="Delimiter">.</span>data<span class="Delimiter">.</span>pop<span class="Delimiter">();</span>
state<span class="Delimiter">.</span>data<span class="Delimiter">.</span>push<span class="Delimiter">(</span>merge_check_point<span class="Delimiter">(</span>variant<span class="Delimiter">,</span> <span class="Constant">0</span><span class="Delimiter">));</span>
++ingredient_index<span class="Delimiter">;</span>
<span class="Identifier">break</span><span class="Delimiter">;</span>
<span class="Delimiter">}</span>
<span class="Delimiter">:(scenario merge_check_container_containing_exclusive_container)</span>
container foo [
x:number
y:bar
]
exclusive-container bar [
x:number
y:number
]
def main [
<span class="Constant">1</span>:foo<span class="Special"> <- </span>merge <span class="Constant">23</span><span class="Delimiter">,</span> <span class="Constant">1</span>/y<span class="Delimiter">,</span> <span class="Constant">34</span>
]
<span class="traceContains">+mem: storing 23 in location 1</span>
<span class="traceContains">+mem: storing 1 in location 2</span>
<span class="traceContains">+mem: storing 34 in location 3</span>
$error: <span class="Constant">0</span>
<span class="Delimiter">:(scenario merge_check_container_containing_exclusive_container_2)</span>
<span class="Special">% Hide_errors = true;</span>
container foo [
x:number
y:bar
]
exclusive-container bar [
x:number
y:number
]
def main [
<span class="Constant">1</span>:foo<span class="Special"> <- </span>merge <span class="Constant">23</span><span class="Delimiter">,</span> <span class="Constant">1</span>/y<span class="Delimiter">,</span> <span class="Constant">34</span><span class="Delimiter">,</span> <span class="Constant">35</span>
]
<span class="traceContains">+error: main: too many ingredients in '1:foo <- merge 23, 1/y, 34, 35'</span>
<span class="Delimiter">:(scenario merge_check_exclusive_container_containing_container)</span>
exclusive-container foo [
x:number
y:bar
]
container bar [
x:number
y:number
]
def main [
<span class="Constant">1</span>:foo<span class="Special"> <- </span>merge <span class="Constant">1</span>/y<span class="Delimiter">,</span> <span class="Constant">23</span><span class="Delimiter">,</span> <span class="Constant">34</span>
]
<span class="traceContains">+mem: storing 1 in location 1</span>
<span class="traceContains">+mem: storing 23 in location 2</span>
<span class="traceContains">+mem: storing 34 in location 3</span>
$error: <span class="Constant">0</span>
<span class="Delimiter">:(scenario merge_check_exclusive_container_containing_container_2)</span>
exclusive-container foo [
x:number
y:bar
]
container bar [
x:number
y:number
]
def main [
<span class="Constant">1</span>:foo<span class="Special"> <- </span>merge <span class="Constant">0</span>/x<span class="Delimiter">,</span> <span class="Constant">23</span>
]
$error: <span class="Constant">0</span>
<span class="Delimiter">:(scenario merge_check_exclusive_container_containing_container_3)</span>
<span class="Special">% Hide_errors = true;</span>
exclusive-container foo [
x:number
y:bar
]
container bar [
x:number
y:number
]
def main [
<span class="Constant">1</span>:foo<span class="Special"> <- </span>merge <span class="Constant">1</span>/y<span class="Delimiter">,</span> <span class="Constant">23</span>
]
<span class="traceContains">+error: main: too few ingredients in '1:foo <- merge 1/y, 23'</span>
<span class="Comment">//: Since the different variants of an exclusive-container might have</span>
<span class="Comment">//: different sizes, relax the size mismatch check for 'merge' instructions.</span>
<span class="Delimiter">:(before "End size_mismatch(x) Cases")</span>
<span class="Normal">if</span> <span class="Delimiter">(</span>current_instruction<span class="Delimiter">().</span>operation == MERGE
&& !current_instruction<span class="Delimiter">().</span>products<span class="Delimiter">.</span>empty<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>type<span class="Delimiter">)</span> <span class="Delimiter">{</span>
reagent x = 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>x<span class="Delimiter">);</span>
<span class="Normal">if</span> <span class="Delimiter">(</span>get<span class="Delimiter">(</span>Type<span class="Delimiter">,</span> x<span class="Delimiter">.</span>type<span class="Delimiter">-></span>value<span class="Delimiter">).</span>kind == EXCLUSIVE_CONTAINER<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span class="Identifier">return</span> size_of<span class="Delimiter">(</span>x<span class="Delimiter">)</span> < SIZE<span class="Delimiter">(</span>data<span class="Delimiter">);</span>
<span class="Delimiter">}</span>
<span class="Delimiter">}</span>
<span class="Delimiter">:(scenario merge_exclusive_container_with_mismatched_sizes)</span>
container foo [
x:number
y:number
]
exclusive-container bar [
x:number
y:foo
]
def main [
<span class="Constant">1</span>:number<span class="Special"> <- </span>copy <span class="Constant">34</span>
<span class="Constant">2</span>:number<span class="Special"> <- </span>copy <span class="Constant">35</span>
<span class="Constant">3</span>:bar<span class="Special"> <- </span>merge <span class="Constant">0</span>/x<span class="Delimiter">,</span> <span class="Constant">1</span>:number
<span class="Constant">6</span>:bar<span class="Special"> <- </span>merge <span class="Constant">1</span>/foo<span class="Delimiter">,</span> <span class="Constant">1</span>:number<span class="Delimiter">,</span> <span class="Constant">2</span>:number
]
<span class="traceContains">+mem: storing 0 in location 3</span>
<span class="traceContains">+mem: storing 34 in location 4</span>
<span class="Comment"># bar is always 3 large so location 5 is skipped</span>
<span class="traceContains">+mem: storing 1 in location 6</span>
<span class="traceContains">+mem: storing 34 in location 7</span>
<span class="traceContains">+mem: storing 35 in location 8</span>
</pre>
</body>
</html>