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<span class="Comment">// A universal hash function that can handle objects of any type.</span>
<span class="Comment">//</span>
<span class="Comment">// The way it's currently implemented, two objects will have the same hash if</span>
<span class="Comment">// all their non-address fields (all the way down) expand to the same sequence</span>
<span class="Comment">// of scalar values. In particular, a container with all zero addresses hashes</span>
<span class="Comment">// to 0. Hopefully this won't be an issue because we are usually hashing</span>
<span class="Comment">// objects of a single type in any given hash table.</span>
<span class="Comment">//</span>
<span class="Comment">// Based on <a href="http://burtleburtle.net/bob/hash/hashfaq.html">http://burtleburtle.net/bob/hash/hashfaq.html</a></span>
<span class="Delimiter">:(before "End Primitive Recipe Declarations")</span>
HASH<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">"hash"</span><span class="Delimiter">,</span> HASH<span class="Delimiter">);</span>
<span class="Delimiter">:(before "End Primitive Recipe Checks")</span>
<span class="Normal">case</span> HASH: <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">1</span><span class="Delimiter">)</span> <span class="Delimiter">{</span>
raise << 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> << <span class="Constant">"'hash' takes exactly one ingredient rather than '"</span> << inst<span class="Delimiter">.</span>original_string << <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="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> HASH: <span class="Delimiter">{</span>
<span class="Normal">const</span> reagent& input = 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>
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>hash<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">,</span> input<span class="Delimiter">));</span>
<span class="Identifier">break</span><span class="Delimiter">;</span>
<span class="Delimiter">}</span>
<span class="Comment">//: in all the code below, the intermediate results of hashing are threaded through 'h'</span>
<span class="Delimiter">:(code)</span>
<span class="Normal">size_t</span> hash<span class="Delimiter">(</span><span class="Normal">size_t</span> h<span class="Delimiter">,</span> reagent<span class="Comment">/*</span><span class="Comment">copy</span><span class="Comment">*/</span> r<span class="Delimiter">)</span> <span class="Delimiter">{</span>
canonize<span class="Delimiter">(</span>r<span class="Delimiter">);</span>
<span class="Normal">if</span> <span class="Delimiter">(</span>is_mu_text<span class="Delimiter">(</span>r<span class="Delimiter">))</span> <span class="Comment">// optimization</span>
<span class="Identifier">return</span> hash_mu_text<span class="Delimiter">(</span>h<span class="Delimiter">,</span> r<span class="Delimiter">);</span>
<span class="Normal">else</span> <span class="Normal">if</span> <span class="Delimiter">(</span>is_mu_address<span class="Delimiter">(</span>r<span class="Delimiter">))</span>
<span class="Identifier">return</span> hash_mu_address<span class="Delimiter">(</span>h<span class="Delimiter">,</span> r<span class="Delimiter">);</span>
<span class="Normal">else</span> <span class="Normal">if</span> <span class="Delimiter">(</span>is_mu_scalar<span class="Delimiter">(</span>r<span class="Delimiter">))</span>
<span class="Identifier">return</span> hash_mu_scalar<span class="Delimiter">(</span>h<span class="Delimiter">,</span> r<span class="Delimiter">);</span>
<span class="Normal">else</span> <span class="Normal">if</span> <span class="Delimiter">(</span>is_mu_array<span class="Delimiter">(</span>r<span class="Delimiter">))</span>
<span class="Identifier">return</span> hash_mu_array<span class="Delimiter">(</span>h<span class="Delimiter">,</span> r<span class="Delimiter">);</span>
<span class="Normal">else</span> <span class="Normal">if</span> <span class="Delimiter">(</span>is_mu_container<span class="Delimiter">(</span>r<span class="Delimiter">))</span>
<span class="Identifier">return</span> hash_mu_container<span class="Delimiter">(</span>h<span class="Delimiter">,</span> r<span class="Delimiter">);</span>
<span class="Normal">else</span> <span class="Normal">if</span> <span class="Delimiter">(</span>is_mu_exclusive_container<span class="Delimiter">(</span>r<span class="Delimiter">))</span>
<span class="Identifier">return</span> hash_mu_exclusive_container<span class="Delimiter">(</span>h<span class="Delimiter">,</span> r<span class="Delimiter">);</span>
assert<span class="Delimiter">(</span><span class="Constant">false</span><span class="Delimiter">);</span>
<span class="Delimiter">}</span>
<span class="Normal">size_t</span> hash_mu_scalar<span class="Delimiter">(</span><span class="Normal">size_t</span> h<span class="Delimiter">,</span> <span class="Normal">const</span> reagent& r<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span class="Normal">double</span> input = is_literal<span class="Delimiter">(</span>r<span class="Delimiter">)</span> ? r<span class="Delimiter">.</span>value : get_or_insert<span class="Delimiter">(</span>Memory<span class="Delimiter">,</span> r<span class="Delimiter">.</span>value<span class="Delimiter">);</span>
<span class="Identifier">return</span> hash_iter<span class="Delimiter">(</span>h<span class="Delimiter">,</span> <span class="Normal">static_cast</span><<span class="Normal">size_t</span>><span class="Delimiter">(</span>input<span class="Delimiter">));</span>
<span class="Delimiter">}</span>
<span class="Normal">size_t</span> hash_mu_address<span class="Delimiter">(</span><span class="Normal">size_t</span> h<span class="Delimiter">,</span> reagent& r<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span class="Normal">if</span> <span class="Delimiter">(</span>r<span class="Delimiter">.</span>value == <span class="Constant">0</span><span class="Delimiter">)</span> <span class="Identifier">return</span> <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">"mem"</span><span class="Delimiter">)</span> << <span class="Constant">"location "</span> << r<span class="Delimiter">.</span>value << <span class="Constant">" is "</span> << no_scientific<span class="Delimiter">(</span>get_or_insert<span class="Delimiter">(</span>Memory<span class="Delimiter">,</span> r<span class="Delimiter">.</span>value<span class="Delimiter">))</span> << end<span class="Delimiter">();</span>
r<span class="Delimiter">.</span>set_value<span class="Delimiter">(</span>get_or_insert<span class="Delimiter">(</span>Memory<span class="Delimiter">,</span> r<span class="Delimiter">.</span>value<span class="Delimiter">));</span>
<span class="Normal">if</span> <span class="Delimiter">(</span>r<span class="Delimiter">.</span>value != <span class="Constant">0</span><span class="Delimiter">)</span> <span class="Delimiter">{</span>
trace<span class="Delimiter">(</span><span class="Constant">9999</span><span class="Delimiter">,</span> <span class="Constant">"mem"</span><span class="Delimiter">)</span> << <span class="Constant">"skipping refcount at "</span> << r<span class="Delimiter">.</span>value << end<span class="Delimiter">();</span>
r<span class="Delimiter">.</span>set_value<span class="Delimiter">(</span>r<span class="Delimiter">.</span>value+<span class="Constant">1</span><span class="Delimiter">);</span> <span class="Comment">// skip refcount</span>
<span class="Delimiter">}</span>
drop_from_type<span class="Delimiter">(</span>r<span class="Delimiter">,</span> <span class="Constant">"address"</span><span class="Delimiter">);</span>
<span class="Identifier">return</span> hash<span class="Delimiter">(</span>h<span class="Delimiter">,</span> r<span class="Delimiter">);</span>
<span class="Delimiter">}</span>
<span class="Normal">size_t</span> hash_mu_text<span class="Delimiter">(</span><span class="Normal">size_t</span> h<span class="Delimiter">,</span> <span class="Normal">const</span> reagent& r<span class="Delimiter">)</span> <span class="Delimiter">{</span>
string input = read_mu_text<span class="Delimiter">(</span>get_or_insert<span class="Delimiter">(</span>Memory<span class="Delimiter">,</span> r<span class="Delimiter">.</span>value<span class="Delimiter">));</span>
<span class="Normal">for</span> <span class="Delimiter">(</span><span class="Normal">int</span> i = <span class="Constant">0</span><span class="Delimiter">;</span> i < SIZE<span class="Delimiter">(</span>input<span class="Delimiter">);</span> ++i<span class="Delimiter">)</span> <span class="Delimiter">{</span>
h = hash_iter<span class="Delimiter">(</span>h<span class="Delimiter">,</span> <span class="Normal">static_cast</span><<span class="Normal">size_t</span>><span class="Delimiter">(</span>input<span class="Delimiter">.</span>at<span class="Delimiter">(</span>i<span class="Delimiter">)));</span>
<span class="CommentedCode">//? cerr << i << ": " << h << '\n';</span>
<span class="Delimiter">}</span>
<span class="Identifier">return</span> h<span class="Delimiter">;</span>
<span class="Delimiter">}</span>
<span class="Normal">size_t</span> hash_mu_array<span class="Delimiter">(</span><span class="Normal">size_t</span> h<span class="Delimiter">,</span> <span class="Normal">const</span> reagent& r<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span class="Normal">int</span> size = get_or_insert<span class="Delimiter">(</span>Memory<span class="Delimiter">,</span> r<span class="Delimiter">.</span>value<span class="Delimiter">);</span>
reagent<span class="Comment">/*</span><span class="Comment">copy</span><span class="Comment">*/</span> elem = r<span class="Delimiter">;</span>
<span class="Normal">delete</span> elem<span class="Delimiter">.</span>type<span class="Delimiter">;</span>
elem<span class="Delimiter">.</span>type = copy_array_element<span class="Delimiter">(</span>r<span class="Delimiter">.</span>type<span class="Delimiter">);</span>
<span class="Normal">for</span> <span class="Delimiter">(</span><span class="Normal">int</span> i=<span class="Constant">0</span><span class="Delimiter">,</span> address = r<span class="Delimiter">.</span>value+<span class="Constant">1</span><span class="Delimiter">;</span> i < size<span class="Delimiter">;</span> ++i<span class="Delimiter">,</span> address += size_of<span class="Delimiter">(</span>elem<span class="Delimiter">))</span> <span class="Delimiter">{</span>
reagent<span class="Comment">/*</span><span class="Comment">copy</span><span class="Comment">*/</span> tmp = elem<span class="Delimiter">;</span>
tmp<span class="Delimiter">.</span>set_value<span class="Delimiter">(</span>address<span class="Delimiter">);</span>
h = hash<span class="Delimiter">(</span>h<span class="Delimiter">,</span> tmp<span class="Delimiter">);</span>
<span class="CommentedCode">//? cerr << i << " (" << address << "): " << h << '\n';</span>
<span class="Delimiter">}</span>
<span class="Identifier">return</span> h<span class="Delimiter">;</span>
<span class="Delimiter">}</span>
<span class="Normal">size_t</span> hash_mu_container<span class="Delimiter">(</span><span class="Normal">size_t</span> h<span class="Delimiter">,</span> <span class="Normal">const</span> reagent& r<span class="Delimiter">)</span> <span class="Delimiter">{</span>
type_info& info = get<span class="Delimiter">(</span>Type<span class="Delimiter">,</span> get_base_type<span class="Delimiter">(</span>r<span class="Delimiter">.</span>type<span class="Delimiter">)-></span>value<span class="Delimiter">);</span>
<span class="Normal">int</span> address = r<span class="Delimiter">.</span>value<span class="Delimiter">;</span>
<span class="Normal">int</span> offset = <span class="Constant">0</span><span class="Delimiter">;</span>
<span class="Normal">for</span> <span class="Delimiter">(</span><span class="Normal">int</span> i = <span class="Constant">0</span><span class="Delimiter">;</span> i < SIZE<span class="Delimiter">(</span>info<span class="Delimiter">.</span>elements<span class="Delimiter">);</span> ++i<span class="Delimiter">)</span> <span class="Delimiter">{</span>
reagent<span class="Comment">/*</span><span class="Comment">copy</span><span class="Comment">*/</span> element = element_type<span class="Delimiter">(</span>r<span class="Delimiter">.</span>type<span class="Delimiter">,</span> i<span class="Delimiter">);</span>
<span class="Normal">if</span> <span class="Delimiter">(</span>has_property<span class="Delimiter">(</span>element<span class="Delimiter">,</span> <span class="Constant">"ignore-for-hash"</span><span class="Delimiter">))</span> <span class="Identifier">continue</span><span class="Delimiter">;</span>
element<span class="Delimiter">.</span>set_value<span class="Delimiter">(</span>address+offset<span class="Delimiter">);</span>
h = hash<span class="Delimiter">(</span>h<span class="Delimiter">,</span> element<span class="Delimiter">);</span>
<span class="CommentedCode">//? cerr << i << ": " << h << '\n';</span>
offset += size_of<span class="Delimiter">(</span>info<span class="Delimiter">.</span>elements<span class="Delimiter">.</span>at<span class="Delimiter">(</span>i<span class="Delimiter">).</span>type<span class="Delimiter">);</span>
<span class="Delimiter">}</span>
<span class="Identifier">return</span> h<span class="Delimiter">;</span>
<span class="Delimiter">}</span>
<span class="Normal">size_t</span> hash_mu_exclusive_container<span class="Delimiter">(</span><span class="Normal">size_t</span> h<span class="Delimiter">,</span> <span class="Normal">const</span> reagent& r<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span class="Normal">const</span> type_tree* type = get_base_type<span class="Delimiter">(</span>r<span class="Delimiter">.</span>type<span class="Delimiter">);</span>
assert<span class="Delimiter">(</span>type<span class="Delimiter">-></span>value<span class="Delimiter">);</span>
<span class="Normal">int</span> tag = get<span class="Delimiter">(</span>Memory<span class="Delimiter">,</span> r<span class="Delimiter">.</span>value<span class="Delimiter">);</span>
reagent<span class="Comment">/*</span><span class="Comment">copy</span><span class="Comment">*/</span> variant = variant_type<span class="Delimiter">(</span>r<span class="Delimiter">,</span> tag<span class="Delimiter">);</span>
<span class="Comment">// todo: move this error to container definition time</span>
<span class="Normal">if</span> <span class="Delimiter">(</span>has_property<span class="Delimiter">(</span>variant<span class="Delimiter">,</span> <span class="Constant">"ignore-for-hash"</span><span class="Delimiter">))</span>
raise << get<span class="Delimiter">(</span>Type<span class="Delimiter">,</span> type<span class="Delimiter">-></span>value<span class="Delimiter">).</span>name << <span class="Constant">": /ignore-for-hash won't work in exclusive containers</span><span class="cSpecial">\n</span><span class="Constant">"</span> << end<span class="Delimiter">();</span>
variant<span class="Delimiter">.</span>set_value<span class="Delimiter">(</span>r<span class="Delimiter">.</span>value + <span class="Comment">/*</span><span class="Comment">skip tag</span><span class="Comment">*/</span><span class="Constant">1</span><span class="Delimiter">);</span>
h = hash<span class="Delimiter">(</span>h<span class="Delimiter">,</span> variant<span class="Delimiter">);</span>
<span class="Identifier">return</span> h<span class="Delimiter">;</span>
<span class="Delimiter">}</span>
<span class="Normal">size_t</span> hash_iter<span class="Delimiter">(</span><span class="Normal">size_t</span> h<span class="Delimiter">,</span> <span class="Normal">size_t</span> input<span class="Delimiter">)</span> <span class="Delimiter">{</span>
h += input<span class="Delimiter">;</span>
h += <span class="Delimiter">(</span>h<<<span class="Constant">10</span><span class="Delimiter">);</span>
h ^= <span class="Delimiter">(</span>h>><span class="Constant">6</span><span class="Delimiter">);</span>
h += <span class="Delimiter">(</span>h<<<span class="Constant">3</span><span class="Delimiter">);</span>
h ^= <span class="Delimiter">(</span>h>><span class="Constant">11</span><span class="Delimiter">);</span>
h += <span class="Delimiter">(</span>h<<<span class="Constant">15</span><span class="Delimiter">);</span>
<span class="Identifier">return</span> h<span class="Delimiter">;</span>
<span class="Delimiter">}</span>
<span class="Delimiter">:(scenario hash_container_checks_all_elements)</span>
<span class="muData">container</span> foo [
<span class="Normal">x</span>:num
<span class="Normal">y</span>:<span class="Normal">char</span>
]
<span class="muRecipe">def</span> main [
<span class="Constant">1</span>:foo<span class="Special"> <- </span>merge <span class="Constant">34</span><span class="Delimiter">,</span> <span class="Constant">97</span>/a
<span class="Constant">3</span>:num<span class="Special"> <- </span>hash <span class="Constant">1</span>:foo
<span class="Identifier">return</span>-unless <span class="Constant">3</span>:num
<span class="Constant">4</span>:foo<span class="Special"> <- </span>merge <span class="Constant">34</span><span class="Delimiter">,</span> <span class="Constant">98</span>/a
<span class="Constant">6</span>:num<span class="Special"> <- </span>hash <span class="Constant">4</span>:foo
<span class="Identifier">return</span>-unless <span class="Constant">6</span>:num
<span class="Constant">7</span>:<span class="Normal">bool</span><span class="Special"> <- </span>equal <span class="Constant">3</span>:num<span class="Delimiter">,</span> <span class="Constant">6</span>:num
]
<span class="Comment"># hash on containers includes all elements</span>
<span class="traceContains">+mem: storing 0 in location 7</span>
<span class="Delimiter">:(scenario hash_exclusive_container_checks_all_elements)</span>
<span class="muData">exclusive-container</span> foo [
<span class="Normal">x</span>:bar
<span class="Normal">y</span>:num
]
<span class="muData">container</span> bar [
<span class="Normal">a</span>:num
<span class="Normal">b</span>:num
]
<span class="muRecipe">def</span> 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="Delimiter">,</span> <span class="Constant">35</span>
<span class="Constant">4</span>:num<span class="Special"> <- </span>hash <span class="Constant">1</span>:foo
<span class="Identifier">return</span>-unless <span class="Constant">4</span>:num
<span class="Constant">5</span>:foo<span class="Special"> <- </span>merge <span class="Constant">0</span>/x<span class="Delimiter">,</span> <span class="Constant">34</span><span class="Delimiter">,</span> <span class="Constant">36</span>
<span class="Constant">8</span>:num<span class="Special"> <- </span>hash <span class="Constant">5</span>:foo
<span class="Identifier">return</span>-unless <span class="Constant">8</span>:num
<span class="Constant">9</span>:<span class="Normal">bool</span><span class="Special"> <- </span>equal <span class="Constant">4</span>:num<span class="Delimiter">,</span> <span class="Constant">8</span>:num
]
<span class="Comment"># hash on containers includes all elements</span>
<span class="traceContains">+mem: storing 0 in location 9</span>
<span class="Delimiter">:(scenario hash_can_ignore_container_elements)</span>
<span class="muData">container</span> foo [
<span class="Normal">x</span>:num
<span class="Normal">y</span>:<span class="Normal">char</span>/ignore-<span class="Normal">for</span>-hash
]
<span class="muRecipe">def</span> main [
<span class="Constant">1</span>:foo<span class="Special"> <- </span>merge <span class="Constant">34</span><span class="Delimiter">,</span> <span class="Constant">97</span>/a
<span class="Constant">3</span>:num<span class="Special"> <- </span>hash <span class="Constant">1</span>:foo
<span class="Identifier">return</span>-unless <span class="Constant">3</span>:num
<span class="Constant">4</span>:foo<span class="Special"> <- </span>merge <span class="Constant">34</span><span class="Delimiter">,</span> <span class="Constant">98</span>/a
<span class="Constant">6</span>:num<span class="Special"> <- </span>hash <span class="Constant">4</span>:foo
<span class="Identifier">return</span>-unless <span class="Constant">6</span>:num
<span class="Constant">7</span>:<span class="Normal">bool</span><span class="Special"> <- </span>equal <span class="Constant">3</span>:num<span class="Delimiter">,</span> <span class="Constant">6</span>:num
]
<span class="Comment"># hashes match even though y is different</span>
<span class="traceContains">+mem: storing 1 in location 7</span>
<span class="Comment">//: These properties aren't necessary for hash, they just test that the</span>
<span class="Comment">//: current implementation works like we think it does.</span>
<span class="Delimiter">:(scenario hash_of_zero_address)</span>
<span class="muRecipe">def</span> main [
<span class="Constant">1</span>:&:num<span class="Special"> <- </span>copy <span class="Constant">0</span>
<span class="Constant">2</span>:num<span class="Special"> <- </span>hash <span class="Constant">1</span>:&:num
]
<span class="traceContains">+mem: storing 0 in location 2</span>
<span class="Comment">//: This is probably too aggressive, but we need some way to avoid depending</span>
<span class="Comment">//: on the precise bit pattern of a floating-point number.</span>
<span class="Delimiter">:(scenario hash_of_numbers_ignores_fractional_part)</span>
<span class="muRecipe">def</span> main [
<span class="Constant">1</span>:num<span class="Special"> <- </span>hash <span class="Constant">1.5</span>
<span class="Constant">2</span>:num<span class="Special"> <- </span>hash <span class="Constant">1</span>
<span class="Constant">3</span>:<span class="Normal">bool</span><span class="Special"> <- </span>equal <span class="Constant">1</span>:num<span class="Delimiter">,</span> <span class="Constant">2</span>:num
]
<span class="traceContains">+mem: storing 1 in location 3</span>
<span class="Delimiter">:(scenario hash_of_array_same_as_string)</span>
<span class="muRecipe">def</span> main [
<span class="Constant">10</span>:num<span class="Special"> <- </span>copy <span class="Constant">3</span>
<span class="Constant">11</span>:num<span class="Special"> <- </span>copy <span class="Constant">97</span>
<span class="Constant">12</span>:num<span class="Special"> <- </span>copy <span class="Constant">98</span>
<span class="Constant">13</span>:num<span class="Special"> <- </span>copy <span class="Constant">99</span>
<span class="Constant">2</span>:num<span class="Special"> <- </span>hash <span class="Constant">10</span>:@:num/unsafe
<span class="Identifier">return</span>-unless <span class="Constant">2</span>:num
<span class="Constant">3</span>:text<span class="Special"> <- </span><span class="Normal">new</span> [abc]
<span class="Constant">4</span>:num<span class="Special"> <- </span>hash <span class="Constant">3</span>:text
<span class="Identifier">return</span>-unless <span class="Constant">4</span>:num
<span class="Constant">5</span>:<span class="Normal">bool</span><span class="Special"> <- </span>equal <span class="Constant">2</span>:num<span class="Delimiter">,</span> <span class="Constant">4</span>:num
]
<span class="traceContains">+mem: storing 1 in location 5</span>
<span class="Delimiter">:(scenario hash_ignores_address_value)</span>
<span class="muRecipe">def</span> main [
<span class="Constant">1</span>:&:num<span class="Special"> <- </span><span class="Normal">new</span> <span class="Constant">number:type</span>
*<span class="Constant">1</span>:&:num<span class="Special"> <- </span>copy <span class="Constant">34</span>
<span class="Constant">2</span>:num<span class="Special"> <- </span>hash <span class="Constant">1</span>:&:num
<span class="Constant">3</span>:&:num<span class="Special"> <- </span><span class="Normal">new</span> <span class="Constant">number:type</span>
*<span class="Constant">3</span>:&:num<span class="Special"> <- </span>copy <span class="Constant">34</span>
<span class="Constant">4</span>:num<span class="Special"> <- </span>hash <span class="Constant">3</span>:&:num
<span class="Constant">5</span>:<span class="Normal">bool</span><span class="Special"> <- </span>equal <span class="Constant">2</span>:num<span class="Delimiter">,</span> <span class="Constant">4</span>:num
]
<span class="Comment"># different addresses hash to the same result as long as the values the point to do so</span>
<span class="traceContains">+mem: storing 1 in location 5</span>
<span class="Delimiter">:(scenario hash_ignores_address_refcount)</span>
<span class="muRecipe">def</span> main [
<span class="Constant">1</span>:&:num<span class="Special"> <- </span><span class="Normal">new</span> <span class="Constant">number:type</span>
*<span class="Constant">1</span>:&:num<span class="Special"> <- </span>copy <span class="Constant">34</span>
<span class="Constant">2</span>:num<span class="Special"> <- </span>hash <span class="Constant">1</span>:&:num
<span class="Identifier">return</span>-unless <span class="Constant">2</span>:num
<span class="Comment"># increment refcount</span>
<span class="Constant">3</span>:&:num<span class="Special"> <- </span>copy <span class="Constant">1</span>:&:num
<span class="Constant">4</span>:num<span class="Special"> <- </span>hash <span class="Constant">3</span>:&:num
<span class="Identifier">return</span>-unless <span class="Constant">4</span>:num
<span class="Constant">5</span>:<span class="Normal">bool</span><span class="Special"> <- </span>equal <span class="Constant">2</span>:num<span class="Delimiter">,</span> <span class="Constant">4</span>:num
]
<span class="Comment"># hash doesn't change when refcount changes</span>
<span class="traceContains">+mem: storing 1 in location 5</span>
<span class="Delimiter">:(scenario hash_container_depends_only_on_elements)</span>
<span class="muData">container</span> foo [
<span class="Normal">x</span>:num
<span class="Normal">y</span>:<span class="Normal">char</span>
]
<span class="muData">container</span> bar [
<span class="Normal">x</span>:num
<span class="Normal">y</span>:<span class="Normal">char</span>
]
<span class="muRecipe">def</span> main [
<span class="Constant">1</span>:foo<span class="Special"> <- </span>merge <span class="Constant">34</span><span class="Delimiter">,</span> <span class="Constant">97</span>/a
<span class="Constant">3</span>:num<span class="Special"> <- </span>hash <span class="Constant">1</span>:foo
<span class="Identifier">return</span>-unless <span class="Constant">3</span>:num
<span class="Constant">4</span>:bar<span class="Special"> <- </span>merge <span class="Constant">34</span><span class="Delimiter">,</span> <span class="Constant">97</span>/a
<span class="Constant">6</span>:num<span class="Special"> <- </span>hash <span class="Constant">4</span>:bar
<span class="Identifier">return</span>-unless <span class="Constant">6</span>:num
<span class="Constant">7</span>:<span class="Normal">bool</span><span class="Special"> <- </span>equal <span class="Constant">3</span>:num<span class="Delimiter">,</span> <span class="Constant">6</span>:num
]
<span class="Comment"># containers with identical elements return identical hashes</span>
<span class="traceContains">+mem: storing 1 in location 7</span>
<span class="Delimiter">:(scenario hash_container_depends_only_on_elements_2)</span>
<span class="muData">container</span> foo [
<span class="Normal">x</span>:num
<span class="Normal">y</span>:<span class="Normal">char</span>
<span class="Normal">z</span>:&:num
]
<span class="muRecipe">def</span> main [
<span class="Constant">1</span>:&:num<span class="Special"> <- </span><span class="Normal">new</span> <span class="Constant">number:type</span>
*<span class="Constant">1</span>:&:num<span class="Special"> <- </span>copy <span class="Constant">34</span>
<span class="Constant">2</span>:foo<span class="Special"> <- </span>merge <span class="Constant">34</span><span class="Delimiter">,</span> <span class="Constant">97</span>/a<span class="Delimiter">,</span> <span class="Constant">1</span>:&:num
<span class="Constant">5</span>:num<span class="Special"> <- </span>hash <span class="Constant">2</span>:foo
<span class="Identifier">return</span>-unless <span class="Constant">5</span>:num
<span class="Constant">6</span>:&:num<span class="Special"> <- </span><span class="Normal">new</span> <span class="Constant">number:type</span>
*<span class="Constant">6</span>:&:num<span class="Special"> <- </span>copy <span class="Constant">34</span>
<span class="Constant">7</span>:foo<span class="Special"> <- </span>merge <span class="Constant">34</span><span class="Delimiter">,</span> <span class="Constant">97</span>/a<span class="Delimiter">,</span> <span class="Constant">6</span>:&:num
<span class="Constant">10</span>:num<span class="Special"> <- </span>hash <span class="Constant">7</span>:foo
<span class="Identifier">return</span>-unless <span class="Constant">10</span>:num
<span class="Constant">11</span>:<span class="Normal">bool</span><span class="Special"> <- </span>equal <span class="Constant">5</span>:num<span class="Delimiter">,</span> <span class="Constant">10</span>:num
]
<span class="Comment"># containers with identical 'leaf' elements return identical hashes</span>
<span class="traceContains">+mem: storing 1 in location 11</span>
<span class="Delimiter">:(scenario hash_container_depends_only_on_elements_3)</span>
<span class="muData">container</span> foo [
<span class="Normal">x</span>:num
<span class="Normal">y</span>:<span class="Normal">char</span>
<span class="Normal">z</span>:bar
]
<span class="muData">container</span> bar [
<span class="Normal">x</span>:num
<span class="Normal">y</span>:num
]
<span class="muRecipe">def</span> main [
<span class="Constant">1</span>:foo<span class="Special"> <- </span>merge <span class="Constant">34</span><span class="Delimiter">,</span> <span class="Constant">97</span>/a<span class="Delimiter">,</span> <span class="Constant">47</span><span class="Delimiter">,</span> <span class="Constant">48</span>
<span class="Constant">6</span>:num<span class="Special"> <- </span>hash <span class="Constant">1</span>:foo
<span class="Identifier">return</span>-unless <span class="Constant">6</span>:num
<span class="Constant">7</span>:foo<span class="Special"> <- </span>merge <span class="Constant">34</span><span class="Delimiter">,</span> <span class="Constant">97</span>/a<span class="Delimiter">,</span> <span class="Constant">47</span><span class="Delimiter">,</span> <span class="Constant">48</span>
<span class="Constant">12</span>:num<span class="Special"> <- </span>hash <span class="Constant">7</span>:foo
<span class="Identifier">return</span>-unless <span class="Constant">12</span>:num
<span class="Constant">13</span>:<span class="Normal">bool</span><span class="Special"> <- </span>equal <span class="Constant">6</span>:num<span class="Delimiter">,</span> <span class="Constant">12</span>:num
]
<span class="Comment"># containers with identical 'leaf' elements return identical hashes</span>
<span class="traceContains">+mem: storing 1 in location 13</span>
<span class="Delimiter">:(scenario hash_exclusive_container_ignores_tag)</span>
<span class="muData">exclusive-container</span> foo [
<span class="Normal">x</span>:bar
<span class="Normal">y</span>:num
]
<span class="muData">container</span> bar [
<span class="Normal">a</span>:num
<span class="Normal">b</span>:num
]
<span class="muRecipe">def</span> 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="Delimiter">,</span> <span class="Constant">35</span>
<span class="Constant">4</span>:num<span class="Special"> <- </span>hash <span class="Constant">1</span>:foo
<span class="Identifier">return</span>-unless <span class="Constant">4</span>:num
<span class="Constant">5</span>:bar<span class="Special"> <- </span>merge <span class="Constant">34</span><span class="Delimiter">,</span> <span class="Constant">35</span>
<span class="Constant">7</span>:num<span class="Special"> <- </span>hash <span class="Constant">5</span>:bar
<span class="Identifier">return</span>-unless <span class="Constant">7</span>:num
<span class="Constant">8</span>:<span class="Normal">bool</span><span class="Special"> <- </span>equal <span class="Constant">4</span>:num<span class="Delimiter">,</span> <span class="Constant">7</span>:num
]
<span class="Comment"># hash on containers includes all elements</span>
<span class="traceContains">+mem: storing 1 in location 8</span>
<span class="Comment">//: An older version that supported only strings.</span>
<span class="Comment">//: Hash functions are subtle and easy to get wrong, so we keep the old</span>
<span class="Comment">//: version around and check that the new one is consistent with it.</span>
<span class="Delimiter">:(scenario hash_matches_old_version)</span>
<span class="muRecipe">def</span> main [
<span class="Constant">1</span>:text<span class="Special"> <- </span><span class="Normal">new</span> [abc]
<span class="Constant">2</span>:num<span class="Special"> <- </span>hash <span class="Constant">1</span>:text
<span class="Constant">3</span>:num<span class="Special"> <- </span>hash_old <span class="Constant">1</span>:text
<span class="Constant">4</span>:<span class="Normal">bool</span><span class="Special"> <- </span>equal <span class="Constant">2</span>:num<span class="Delimiter">,</span> <span class="Constant">3</span>:num
]
<span class="traceContains">+mem: storing 1 in location 4</span>
<span class="Delimiter">:(before "End Primitive Recipe Declarations")</span>
HASH_OLD<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">"hash_old"</span><span class="Delimiter">,</span> HASH_OLD<span class="Delimiter">);</span>
<span class="Delimiter">:(before "End Primitive Recipe Checks")</span>
<span class="Normal">case</span> HASH_OLD: <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">1</span><span class="Delimiter">)</span> <span class="Delimiter">{</span>
raise << 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> << <span class="Constant">"'hash_old' takes exactly one ingredient rather than '"</span> << inst<span class="Delimiter">.</span>original_string << <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">if</span> <span class="Delimiter">(</span>!is_mu_text<span class="Delimiter">(</span>inst<span class="Delimiter">.</span>ingredients<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">)))</span> <span class="Delimiter">{</span>
raise << 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> << <span class="Constant">"'hash_old' currently only supports texts (address array character), but got '"</span> << inst<span class="Delimiter">.</span>ingredients<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">).</span>original_string << <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="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> HASH_OLD: <span class="Delimiter">{</span>
string input = read_mu_text<span class="Delimiter">(</span>ingredients<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">).</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">));</span>
<span class="Normal">size_t</span> h = <span class="Constant">0</span> <span class="Delimiter">;</span>
<span class="Normal">for</span> <span class="Delimiter">(</span><span class="Normal">int</span> i = <span class="Constant">0</span><span class="Delimiter">;</span> i < SIZE<span class="Delimiter">(</span>input<span class="Delimiter">);</span> ++i<span class="Delimiter">)</span> <span class="Delimiter">{</span>
h += <span class="Normal">static_cast</span><<span class="Normal">size_t</span>><span class="Delimiter">(</span>input<span class="Delimiter">.</span>at<span class="Delimiter">(</span>i<span class="Delimiter">));</span>
h += <span class="Delimiter">(</span>h<<<span class="Constant">10</span><span class="Delimiter">);</span>
h ^= <span class="Delimiter">(</span>h>><span class="Constant">6</span><span class="Delimiter">);</span>
h += <span class="Delimiter">(</span>h<<<span class="Constant">3</span><span class="Delimiter">);</span>
h ^= <span class="Delimiter">(</span>h>><span class="Constant">11</span><span class="Delimiter">);</span>
h += <span class="Delimiter">(</span>h<<<span class="Constant">15</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>h<span class="Delimiter">);</span>
<span class="Identifier">break</span><span class="Delimiter">;</span>
<span class="Delimiter">}</span>
</pre>
</body>
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