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373 lines
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<ul><li><a href="../inweb/index.html">inweb</a></li>
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<!--Weave of 'Dictionaries' generated by Inweb-->
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<div class="breadcrumbs">
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<ul class="crumbs"><li><a href="../index.html">Home</a></li><li><a href="index.html">foundation</a></li><li><a href="index.html#2">Chapter 2: Memory, Streams and Collections</a></li><li><b>Dictionaries</b></li></ul></div>
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<p class="purpose">A simple implementation for a flexible-sized dictionary of key-value pairs.</p>
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<ul class="toc"><li><a href="2-dct.html#SP1">§1. Storage</a></li><li><a href="2-dct.html#SP2">§2. Creation</a></li><li><a href="2-dct.html#SP3">§3. Logging</a></li><li><a href="2-dct.html#SP4">§4. Hashing</a></li><li><a href="2-dct.html#SP5">§5. Create, find, destroy</a></li><li><a href="2-dct.html#SP8">§8. Accessing entries</a></li><li><a href="2-dct.html#SP11">§11. Disposal</a></li></ul><hr class="tocbar">
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<p class="commentary firstcommentary"><a id="SP1"></a><b>§1. Storage. </b>There's nothing fancy here. A "dictionary" is a hash table allowing reasonably
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efficient lookup: it's a correspondence between "keys", which are texts, and
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pointers to some external structure. Often these will also be texts, but
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not necessarily.
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</p>
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<pre class="displayed-code all-displayed-code code-font">
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<span class="reserved-syntax">typedef</span><span class="plain-syntax"> </span><span class="reserved-syntax">struct</span><span class="plain-syntax"> </span><span class="reserved-syntax">dictionary</span><span class="plain-syntax"> {</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">textual</span><span class="plain-syntax">; </span><span class="comment-syntax"> values are texts?</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">no_entries</span><span class="plain-syntax">; </span><span class="comment-syntax"> total number of key-value pairs currently stored here</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">hash_table_size</span><span class="plain-syntax">; </span><span class="comment-syntax"> size of array...</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">struct</span><span class="plain-syntax"> </span><span class="reserved-syntax">dict_entry</span><span class="plain-syntax"> *</span><span class="identifier-syntax">hash_table</span><span class="plain-syntax">; </span><span class="comment-syntax"> ...of linked lists of dictionary entries</span>
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<span class="plain-syntax"> </span><span class="constant-syntax">CLASS_DEFINITION</span>
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<span class="plain-syntax">} </span><span class="reserved-syntax">dictionary</span><span class="plain-syntax">;</span>
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<span class="reserved-syntax">typedef</span><span class="plain-syntax"> </span><span class="reserved-syntax">struct</span><span class="plain-syntax"> </span><span class="reserved-syntax">dict_entry</span><span class="plain-syntax"> {</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">vacant</span><span class="plain-syntax">; </span><span class="comment-syntax"> a "vacant" entry is not currently used to store a k-v pair</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">struct</span><span class="plain-syntax"> </span><span class="reserved-syntax">text_stream</span><span class="plain-syntax"> *</span><span class="identifier-syntax">key</span><span class="plain-syntax">; </span><span class="comment-syntax"> for non-vacant entries only: the key text</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">void</span><span class="plain-syntax"> *</span><span class="identifier-syntax">value</span><span class="plain-syntax">; </span><span class="comment-syntax"> for non-vacant entries only: the value, some kind of pointer</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">struct</span><span class="plain-syntax"> </span><span class="reserved-syntax">dict_entry</span><span class="plain-syntax"> *</span><span class="identifier-syntax">next_in_entry</span><span class="plain-syntax">;</span>
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<span class="plain-syntax">} </span><span class="reserved-syntax">dict_entry</span><span class="plain-syntax">;</span>
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</pre>
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<ul class="endnotetexts"><li>The structure dictionary is private to this section.</li><li>The structure dict_entry is accessed in 5/ee, 8/bdfw and here.</li></ul>
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<p class="commentary firstcommentary"><a id="SP2"></a><b>§2. Creation. </b>Dictionaries can have arbitrary size, in that they expand as needed, but for
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efficiency's sake the caller can set them up with an initial size of her choice.
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</p>
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<pre class="displayed-code all-displayed-code code-font">
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<span class="reserved-syntax">dictionary</span><span class="plain-syntax"> *</span><span class="function-syntax">Dictionaries::new</span><button class="popup" onclick="togglePopup('usagePopup1')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup1">Usage of <span class="code-font"><span class="function-syntax">Dictionaries::new</span></span>:<br/><a href="2-dct.html#SP7_2">§7.2</a><br/>Command Line Arguments - <a href="3-cla.html#SP5">§5</a><br/>String Manipulation - <a href="4-sm.html#SP27_1">§27.1</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">S</span><span class="plain-syntax">, </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">textual</span><span class="plain-syntax">) {</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">S</span><span class="plain-syntax"> < </span><span class="constant-syntax">2</span><span class="plain-syntax">) </span><span class="identifier-syntax">internal_error</span><span class="plain-syntax">(</span><span class="string-syntax">"dictionary too small"</span><span class="plain-syntax">);</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">dictionary</span><span class="plain-syntax"> *</span><span class="identifier-syntax">D</span><span class="plain-syntax"> = </span><span class="identifier-syntax">CREATE</span><span class="plain-syntax">(</span><span class="reserved-syntax">dictionary</span><span class="plain-syntax">);</span>
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<span class="plain-syntax"> </span><span class="identifier-syntax">D</span><span class="plain-syntax">-></span><span class="element-syntax">textual</span><span class="plain-syntax"> = </span><span class="identifier-syntax">textual</span><span class="plain-syntax">;</span>
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<span class="plain-syntax"> </span><span class="identifier-syntax">D</span><span class="plain-syntax">-></span><span class="element-syntax">hash_table_size</span><span class="plain-syntax"> = </span><span class="identifier-syntax">S</span><span class="plain-syntax">;</span>
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<span class="plain-syntax"> </span><span class="identifier-syntax">D</span><span class="plain-syntax">-></span><span class="element-syntax">no_entries</span><span class="plain-syntax"> = </span><span class="constant-syntax">0</span><span class="plain-syntax">;</span>
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<span class="plain-syntax"> </span><span class="identifier-syntax">D</span><span class="plain-syntax">-></span><span class="element-syntax">hash_table</span><span class="plain-syntax"> = </span><a href="2-mmr.html#SP24" class="function-link"><span class="function-syntax">Memory::calloc</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">S</span><span class="plain-syntax">, </span><span class="reserved-syntax">sizeof</span><span class="plain-syntax">(</span><span class="reserved-syntax">dict_entry</span><span class="plain-syntax">), </span><span class="constant-syntax">DICTIONARY_MREASON</span><span class="plain-syntax">);</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">for</span><span class="plain-syntax"> (</span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">i</span><span class="plain-syntax">=0; </span><span class="identifier-syntax">i</span><span class="plain-syntax"><</span><span class="identifier-syntax">S</span><span class="plain-syntax">; </span><span class="identifier-syntax">i</span><span class="plain-syntax">++) {</span>
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<span class="plain-syntax"> </span><span class="identifier-syntax">D</span><span class="plain-syntax">-></span><span class="identifier-syntax">hash_table</span><span class="plain-syntax">[</span><span class="identifier-syntax">i</span><span class="plain-syntax">].</span><span class="element-syntax">vacant</span><span class="plain-syntax"> = </span><span class="constant-syntax">TRUE</span><span class="plain-syntax">;</span>
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<span class="plain-syntax"> </span><span class="identifier-syntax">D</span><span class="plain-syntax">-></span><span class="identifier-syntax">hash_table</span><span class="plain-syntax">[</span><span class="identifier-syntax">i</span><span class="plain-syntax">].</span><span class="element-syntax">value</span><span class="plain-syntax"> = </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">;</span>
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<span class="plain-syntax"> </span><span class="identifier-syntax">D</span><span class="plain-syntax">-></span><span class="identifier-syntax">hash_table</span><span class="plain-syntax">[</span><span class="identifier-syntax">i</span><span class="plain-syntax">].</span><span class="element-syntax">next_in_entry</span><span class="plain-syntax"> = </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">;</span>
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<span class="plain-syntax"> }</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">D</span><span class="plain-syntax">;</span>
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<span class="plain-syntax">}</span>
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</pre>
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<p class="commentary firstcommentary"><a id="SP3"></a><b>§3. Logging. </b></p>
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<pre class="displayed-code all-displayed-code code-font">
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<span class="reserved-syntax">void</span><span class="plain-syntax"> </span><span class="function-syntax">Dictionaries::log</span><span class="plain-syntax">(</span><span class="constant-syntax">OUTPUT_STREAM</span><span class="plain-syntax">, </span><span class="reserved-syntax">dictionary</span><span class="plain-syntax"> *</span><span class="identifier-syntax">D</span><span class="plain-syntax">) {</span>
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<span class="plain-syntax"> </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"Dictionary:\n"</span><span class="plain-syntax">, (</span><span class="reserved-syntax">unsigned</span><span class="plain-syntax"> </span><span class="reserved-syntax">int</span><span class="plain-syntax">) </span><span class="identifier-syntax">D</span><span class="plain-syntax">); </span><span class="constant-syntax">INDENT</span><span class="plain-syntax">;</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">for</span><span class="plain-syntax"> (</span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">i</span><span class="plain-syntax">=0; </span><span class="identifier-syntax">i</span><span class="function-syntax"><D-></span><span class="element-syntax">hash_table_size</span><span class="plain-syntax">; </span><span class="identifier-syntax">i</span><span class="plain-syntax">++) {</span>
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<span class="plain-syntax"> </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"Slot %02d:"</span><span class="plain-syntax">, </span><span class="identifier-syntax">i</span><span class="plain-syntax">);</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">for</span><span class="plain-syntax"> (</span><span class="reserved-syntax">dict_entry</span><span class="plain-syntax"> *</span><span class="identifier-syntax">E</span><span class="plain-syntax"> = &(</span><span class="identifier-syntax">D</span><span class="plain-syntax">-></span><span class="element-syntax">hash_table</span><span class="plain-syntax">[</span><span class="identifier-syntax">i</span><span class="plain-syntax">]); </span><span class="identifier-syntax">E</span><span class="plain-syntax">; </span><span class="identifier-syntax">E</span><span class="plain-syntax"> = </span><span class="identifier-syntax">E</span><span class="plain-syntax">-></span><span class="element-syntax">next_in_entry</span><span class="plain-syntax">)</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">E</span><span class="plain-syntax">-></span><span class="element-syntax">vacant</span><span class="plain-syntax">) </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">" vacant"</span><span class="plain-syntax">);</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">else</span><span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">D</span><span class="plain-syntax">-></span><span class="element-syntax">textual</span><span class="plain-syntax">) </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">" %S='%S'"</span><span class="plain-syntax">, </span><span class="identifier-syntax">E</span><span class="plain-syntax">-></span><span class="element-syntax">key</span><span class="plain-syntax">, </span><span class="identifier-syntax">E</span><span class="plain-syntax">-></span><span class="element-syntax">value</span><span class="plain-syntax">);</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">else</span><span class="plain-syntax"> </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">" %S=%08x"</span><span class="plain-syntax">, </span><span class="identifier-syntax">E</span><span class="plain-syntax">-></span><span class="element-syntax">key</span><span class="plain-syntax">, (</span><span class="reserved-syntax">unsigned</span><span class="plain-syntax"> </span><span class="reserved-syntax">int</span><span class="plain-syntax">) </span><span class="identifier-syntax">E</span><span class="plain-syntax">-></span><span class="element-syntax">value</span><span class="plain-syntax">);</span>
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<span class="plain-syntax"> </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"\n"</span><span class="plain-syntax">);</span>
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<span class="plain-syntax"> }</span>
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<span class="plain-syntax"> </span><span class="constant-syntax">OUTDENT</span><span class="plain-syntax">;</span>
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<span class="plain-syntax">}</span>
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</pre>
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<p class="commentary firstcommentary"><a id="SP4"></a><b>§4. Hashing. </b>The whole point of a hash table is that it crudely sorts the contents by a rough
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indication of the key values. This crude indication is the hash value, calculated
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here. If there are <span class="extract"><span class="extract-syntax">N</span></span> slots in the dictionary table, this tells us which slot
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(from 0 to <span class="extract"><span class="extract-syntax">N-1</span></span>) a given key value belongs in.
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</p>
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<pre class="displayed-code all-displayed-code code-font">
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<span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="function-syntax">Dictionaries::hash</span><button class="popup" onclick="togglePopup('usagePopup2')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup2">Usage of <span class="code-font"><span class="function-syntax">Dictionaries::hash</span></span>:<br/><a href="2-dct.html#SP7_3">§7.3</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">text_stream</span><span class="plain-syntax"> *</span><span class="identifier-syntax">K</span><span class="plain-syntax">, </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">N</span><span class="plain-syntax">) {</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">unsigned</span><span class="plain-syntax"> </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">hash</span><span class="plain-syntax"> = </span><span class="constant-syntax">0</span><span class="plain-syntax">;</span>
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<span class="plain-syntax"> </span><span class="identifier-syntax">LOOP_THROUGH_TEXT</span><span class="plain-syntax">(</span><span class="identifier-syntax">P</span><span class="plain-syntax">, </span><span class="identifier-syntax">K</span><span class="plain-syntax">)</span>
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<span class="plain-syntax"> </span><span class="identifier-syntax">hash</span><span class="plain-syntax"> = </span><span class="constant-syntax">16339</span><span class="plain-syntax">*</span><span class="identifier-syntax">hash</span><span class="plain-syntax"> + ((</span><span class="reserved-syntax">unsigned</span><span class="plain-syntax"> </span><span class="reserved-syntax">int</span><span class="plain-syntax">) </span><a href="4-sm.html#SP13" class="function-link"><span class="function-syntax">Str::get</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">P</span><span class="plain-syntax">));</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax"> (</span><span class="reserved-syntax">int</span><span class="plain-syntax">) (</span><span class="identifier-syntax">hash</span><span class="plain-syntax"> % ((</span><span class="reserved-syntax">unsigned</span><span class="plain-syntax"> </span><span class="reserved-syntax">int</span><span class="plain-syntax">) </span><span class="identifier-syntax">N</span><span class="plain-syntax">));</span>
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<span class="plain-syntax">}</span>
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</pre>
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<p class="commentary firstcommentary"><a id="SP5"></a><b>§5. Create, find, destroy. </b>These three fundamental operations locate the dictionary entry structure for
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a given key value, and then do something to/with it. Note that these pointers
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remain valid only until somebody writes a new value into the dictionary;
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so be careful if thread safety's an issue.
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</p>
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<pre class="displayed-code all-displayed-code code-font">
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<span class="reserved-syntax">dict_entry</span><span class="plain-syntax"> *</span><span class="function-syntax">Dictionaries::find</span><button class="popup" onclick="togglePopup('usagePopup3')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup3">Usage of <span class="code-font"><span class="function-syntax">Dictionaries::find</span></span>:<br/><a href="2-dct.html#SP6">§6</a>, <a href="2-dct.html#SP8">§8</a>, <a href="2-dct.html#SP10">§10</a><br/>Command Line Arguments - <a href="3-cla.html#SP13">§13</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">dictionary</span><span class="plain-syntax"> *</span><span class="identifier-syntax">D</span><span class="plain-syntax">, </span><span class="reserved-syntax">text_stream</span><span class="plain-syntax"> *</span><span class="identifier-syntax">K</span><span class="plain-syntax">) {</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><a href="2-dct.html#SP7" class="function-link"><span class="function-syntax">Dictionaries::find_p</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">D</span><span class="plain-syntax">, </span><span class="identifier-syntax">K</span><span class="plain-syntax">, </span><span class="constant-syntax">0</span><span class="plain-syntax">);</span>
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<span class="plain-syntax">}</span>
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<span class="reserved-syntax">dict_entry</span><span class="plain-syntax"> *</span><span class="function-syntax">Dictionaries::create</span><button class="popup" onclick="togglePopup('usagePopup4')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup4">Usage of <span class="code-font"><span class="function-syntax">Dictionaries::create</span></span>:<br/><a href="2-dct.html#SP6">§6</a>, <a href="2-dct.html#SP9">§9</a><br/>Command Line Arguments - <a href="3-cla.html#SP5">§5</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">dictionary</span><span class="plain-syntax"> *</span><span class="identifier-syntax">D</span><span class="plain-syntax">, </span><span class="reserved-syntax">text_stream</span><span class="plain-syntax"> *</span><span class="identifier-syntax">K</span><span class="plain-syntax">) {</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><a href="2-dct.html#SP7" class="function-link"><span class="function-syntax">Dictionaries::find_p</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">D</span><span class="plain-syntax">, </span><span class="identifier-syntax">K</span><span class="plain-syntax">, </span><span class="constant-syntax">1</span><span class="plain-syntax">);</span>
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<span class="plain-syntax">}</span>
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<span class="reserved-syntax">void</span><span class="plain-syntax"> </span><span class="function-syntax">Dictionaries::destroy</span><button class="popup" onclick="togglePopup('usagePopup5')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup5">Usage of <span class="code-font"><span class="function-syntax">Dictionaries::destroy</span></span>:<br/><a href="2-dct.html#SP6">§6</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">dictionary</span><span class="plain-syntax"> *</span><span class="identifier-syntax">D</span><span class="plain-syntax">, </span><span class="reserved-syntax">text_stream</span><span class="plain-syntax"> *</span><span class="identifier-syntax">K</span><span class="plain-syntax">) {</span>
|
|
<span class="plain-syntax"> </span><a href="2-dct.html#SP7" class="function-link"><span class="function-syntax">Dictionaries::find_p</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">D</span><span class="plain-syntax">, </span><span class="identifier-syntax">K</span><span class="plain-syntax">, -1);</span>
|
|
<span class="plain-syntax">}</span>
|
|
</pre>
|
|
<p class="commentary firstcommentary"><a id="SP6"></a><b>§6. </b>A nuisance we have to live with is that we often want to express the key
|
|
as wide text (so that we can use literals like <span class="extract"><span class="extract-syntax">L"my-key"</span></span>) instead of text
|
|
streams. So we also offer versions suffixed <span class="extract"><span class="extract-syntax">_literal</span></span>:
|
|
</p>
|
|
|
|
<pre class="displayed-code all-displayed-code code-font">
|
|
<span class="reserved-syntax">dict_entry</span><span class="plain-syntax"> *</span><span class="function-syntax">Dictionaries::find_literal</span><button class="popup" onclick="togglePopup('usagePopup6')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup6">Usage of <span class="code-font"><span class="function-syntax">Dictionaries::find_literal</span></span>:<br/><a href="2-dct.html#SP8">§8</a>, <a href="2-dct.html#SP10">§10</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">dictionary</span><span class="plain-syntax"> *</span><span class="identifier-syntax">D</span><span class="plain-syntax">, </span><span class="identifier-syntax">wchar_t</span><span class="plain-syntax"> *</span><span class="identifier-syntax">lit</span><span class="plain-syntax">) {</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">TEMPORARY_TEXT</span><span class="plain-syntax">(</span><span class="identifier-syntax">K</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">WRITE_TO</span><span class="plain-syntax">(</span><span class="identifier-syntax">K</span><span class="plain-syntax">, </span><span class="string-syntax">"%w"</span><span class="plain-syntax">, </span><span class="identifier-syntax">lit</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">dict_entry</span><span class="plain-syntax"> *</span><span class="identifier-syntax">E</span><span class="plain-syntax"> = </span><a href="2-dct.html#SP5" class="function-link"><span class="function-syntax">Dictionaries::find</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">D</span><span class="plain-syntax">, </span><span class="identifier-syntax">K</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">DISCARD_TEXT</span><span class="plain-syntax">(</span><span class="identifier-syntax">K</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">E</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax">}</span>
|
|
<span class="reserved-syntax">dict_entry</span><span class="plain-syntax"> *</span><span class="function-syntax">Dictionaries::create_literal</span><button class="popup" onclick="togglePopup('usagePopup7')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup7">Usage of <span class="code-font"><span class="function-syntax">Dictionaries::create_literal</span></span>:<br/><a href="2-dct.html#SP9">§9</a><br/>String Manipulation - <a href="4-sm.html#SP27_1">§27.1</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">dictionary</span><span class="plain-syntax"> *</span><span class="identifier-syntax">D</span><span class="plain-syntax">, </span><span class="identifier-syntax">wchar_t</span><span class="plain-syntax"> *</span><span class="identifier-syntax">lit</span><span class="plain-syntax">) {</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">TEMPORARY_TEXT</span><span class="plain-syntax">(</span><span class="identifier-syntax">K</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">WRITE_TO</span><span class="plain-syntax">(</span><span class="identifier-syntax">K</span><span class="plain-syntax">, </span><span class="string-syntax">"%w"</span><span class="plain-syntax">, </span><span class="identifier-syntax">lit</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">dict_entry</span><span class="plain-syntax"> *</span><span class="identifier-syntax">E</span><span class="plain-syntax"> = </span><a href="2-dct.html#SP5" class="function-link"><span class="function-syntax">Dictionaries::create</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">D</span><span class="plain-syntax">, </span><span class="identifier-syntax">K</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">DISCARD_TEXT</span><span class="plain-syntax">(</span><span class="identifier-syntax">K</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">E</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax">}</span>
|
|
<span class="reserved-syntax">void</span><span class="plain-syntax"> </span><span class="function-syntax">Dictionaries::destroy_literal</span><span class="plain-syntax">(</span><span class="reserved-syntax">dictionary</span><span class="plain-syntax"> *</span><span class="identifier-syntax">D</span><span class="plain-syntax">, </span><span class="identifier-syntax">wchar_t</span><span class="plain-syntax"> *</span><span class="identifier-syntax">lit</span><span class="plain-syntax">) {</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">TEMPORARY_TEXT</span><span class="plain-syntax">(</span><span class="identifier-syntax">K</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">WRITE_TO</span><span class="plain-syntax">(</span><span class="identifier-syntax">K</span><span class="plain-syntax">, </span><span class="string-syntax">"%w"</span><span class="plain-syntax">, </span><span class="identifier-syntax">lit</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><a href="2-dct.html#SP5" class="function-link"><span class="function-syntax">Dictionaries::destroy</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">D</span><span class="plain-syntax">, </span><span class="identifier-syntax">K</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">DISCARD_TEXT</span><span class="plain-syntax">(</span><span class="identifier-syntax">K</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax">}</span>
|
|
</pre>
|
|
<p class="commentary firstcommentary"><a id="SP7"></a><b>§7. </b>So, then, find an entry (if <span class="extract"><span class="extract-syntax">change</span></span> is <span class="extract"><span class="extract-syntax">0</span></span>), create it (if <span class="extract"><span class="extract-syntax">+1</span></span>) or delete
|
|
it (if <span class="extract"><span class="extract-syntax">-1</span></span>).
|
|
</p>
|
|
|
|
<pre class="displayed-code all-displayed-code code-font">
|
|
<span class="reserved-syntax">dict_entry</span><span class="plain-syntax"> *</span><span class="function-syntax">Dictionaries::find_p</span><button class="popup" onclick="togglePopup('usagePopup8')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup8">Usage of <span class="code-font"><span class="function-syntax">Dictionaries::find_p</span></span>:<br/><a href="2-dct.html#SP5">§5</a>, <a href="2-dct.html#SP7_2">§7.2</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">dictionary</span><span class="plain-syntax"> *</span><span class="identifier-syntax">D</span><span class="plain-syntax">, </span><span class="reserved-syntax">text_stream</span><span class="plain-syntax"> *</span><span class="identifier-syntax">K</span><span class="plain-syntax">, </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">change</span><span class="plain-syntax">) {</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">D</span><span class="plain-syntax"> == </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">) </span><span class="named-paragraph-container code-font"><a href="2-dct.html#SP7_1" class="named-paragraph-link"><span class="named-paragraph">Handle the null dictionary</span><span class="named-paragraph-number">7.1</span></a></span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">change</span><span class="plain-syntax"> == </span><span class="constant-syntax">1</span><span class="plain-syntax">) </span><span class="named-paragraph-container code-font"><a href="2-dct.html#SP7_2" class="named-paragraph-link"><span class="named-paragraph">Expand the dictionary if necessary</span><span class="named-paragraph-number">7.2</span></a></span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="named-paragraph-container code-font"><a href="2-dct.html#SP7_3" class="named-paragraph-link"><span class="named-paragraph">Work within the existing dictionary</span><span class="named-paragraph-number">7.3</span></a></span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax">}</span>
|
|
</pre>
|
|
<p class="commentary firstcommentary"><a id="SP7_1"></a><b>§7.1. </b>It's legal to perform a find on the null dictionary: the answer's always "no".
|
|
</p>
|
|
|
|
<p class="commentary"><span class="named-paragraph-container code-font"><span class="named-paragraph-defn">Handle the null dictionary</span><span class="named-paragraph-number">7.1</span></span><span class="comment-syntax"> =</span>
|
|
</p>
|
|
|
|
<pre class="displayed-code all-displayed-code code-font">
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">change</span><span class="plain-syntax"> == </span><span class="constant-syntax">0</span><span class="plain-syntax">) </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">internal_error</span><span class="plain-syntax">(</span><span class="string-syntax">"tried to create or destroy in a null dictionary"</span><span class="plain-syntax">);</span>
|
|
</pre>
|
|
<ul class="endnotetexts"><li>This code is used in <a href="2-dct.html#SP7">§7</a>.</li></ul>
|
|
<p class="commentary firstcommentary"><a id="SP7_2"></a><b>§7.2. </b>For speed, our policy is that the hash table should have roughly the
|
|
same number of slots as there are entries in the dictionary; that way, each
|
|
slot will have an average of one or fewer entries. When we exceed this
|
|
ideal population, we double the dictionary's capacity.
|
|
</p>
|
|
|
|
<p class="commentary"><span class="named-paragraph-container code-font"><span class="named-paragraph-defn">Expand the dictionary if necessary</span><span class="named-paragraph-number">7.2</span></span><span class="comment-syntax"> =</span>
|
|
</p>
|
|
|
|
<pre class="displayed-code all-displayed-code code-font">
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">D</span><span class="plain-syntax">-></span><span class="identifier-syntax">no_entries</span><span class="plain-syntax"> > </span><span class="identifier-syntax">D</span><span class="plain-syntax">-></span><span class="element-syntax">hash_table_size</span><span class="plain-syntax">) {</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">dictionary</span><span class="plain-syntax"> *</span><span class="identifier-syntax">D2</span><span class="plain-syntax"> = </span><a href="2-dct.html#SP2" class="function-link"><span class="function-syntax">Dictionaries::new</span></a><span class="plain-syntax">(2*</span><span class="identifier-syntax">D</span><span class="plain-syntax">-></span><span class="element-syntax">hash_table_size</span><span class="plain-syntax">, </span><span class="identifier-syntax">D</span><span class="plain-syntax">-></span><span class="element-syntax">textual</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">for</span><span class="plain-syntax"> (</span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">i</span><span class="plain-syntax">=0; </span><span class="identifier-syntax">i</span><span class="function-syntax"><D-></span><span class="element-syntax">hash_table_size</span><span class="plain-syntax">; </span><span class="identifier-syntax">i</span><span class="plain-syntax">++)</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">for</span><span class="plain-syntax"> (</span><span class="reserved-syntax">dict_entry</span><span class="plain-syntax"> *</span><span class="identifier-syntax">E</span><span class="plain-syntax"> = &(</span><span class="identifier-syntax">D</span><span class="plain-syntax">-></span><span class="element-syntax">hash_table</span><span class="plain-syntax">[</span><span class="identifier-syntax">i</span><span class="plain-syntax">]); </span><span class="identifier-syntax">E</span><span class="plain-syntax">; </span><span class="identifier-syntax">E</span><span class="plain-syntax"> = </span><span class="identifier-syntax">E</span><span class="plain-syntax">-></span><span class="element-syntax">next_in_entry</span><span class="plain-syntax">)</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">E</span><span class="plain-syntax">-></span><span class="element-syntax">vacant</span><span class="plain-syntax"> == </span><span class="constant-syntax">FALSE</span><span class="plain-syntax">) {</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">dict_entry</span><span class="plain-syntax"> *</span><span class="identifier-syntax">E2</span><span class="plain-syntax"> = </span><a href="2-dct.html#SP7" class="function-link"><span class="function-syntax">Dictionaries::find_p</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">D2</span><span class="plain-syntax">, </span><span class="identifier-syntax">E</span><span class="plain-syntax">-></span><span class="element-syntax">key</span><span class="plain-syntax">, </span><span class="constant-syntax">1</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">E2</span><span class="plain-syntax">-></span><span class="element-syntax">value</span><span class="plain-syntax"> = </span><span class="identifier-syntax">E</span><span class="plain-syntax">-></span><span class="element-syntax">value</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> }</span>
|
|
<span class="plain-syntax"> </span><a href="2-mmr.html#SP26" class="function-link"><span class="function-syntax">Memory::I7_free</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">D</span><span class="plain-syntax">-></span><span class="element-syntax">hash_table</span><span class="plain-syntax">, </span><span class="constant-syntax">DICTIONARY_MREASON</span><span class="plain-syntax">,</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">D</span><span class="plain-syntax">-></span><span class="element-syntax">hash_table_size</span><span class="plain-syntax">*((</span><span class="reserved-syntax">int</span><span class="plain-syntax">) </span><span class="reserved-syntax">sizeof</span><span class="plain-syntax">(</span><span class="reserved-syntax">dict_entry</span><span class="plain-syntax">)));</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">D</span><span class="plain-syntax">-></span><span class="identifier-syntax">hash_table_size</span><span class="plain-syntax"> = </span><span class="identifier-syntax">D2</span><span class="plain-syntax">-></span><span class="identifier-syntax">hash_table_size</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">D</span><span class="plain-syntax">-></span><span class="identifier-syntax">hash_table</span><span class="plain-syntax"> = </span><span class="identifier-syntax">D2</span><span class="plain-syntax">-></span><span class="element-syntax">hash_table</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> }</span>
|
|
</pre>
|
|
<ul class="endnotetexts"><li>This code is used in <a href="2-dct.html#SP7">§7</a>.</li></ul>
|
|
<p class="commentary firstcommentary"><a id="SP7_3"></a><b>§7.3. </b><span class="named-paragraph-container code-font"><span class="named-paragraph-defn">Work within the existing dictionary</span><span class="named-paragraph-number">7.3</span></span><span class="comment-syntax"> =</span>
|
|
</p>
|
|
|
|
<pre class="displayed-code all-displayed-code code-font">
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">dict_entry</span><span class="plain-syntax"> *</span><span class="identifier-syntax">last_E</span><span class="plain-syntax"> = </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">for</span><span class="plain-syntax"> (</span><span class="reserved-syntax">dict_entry</span><span class="plain-syntax"> *</span><span class="identifier-syntax">E</span><span class="plain-syntax"> = &(</span><span class="identifier-syntax">D</span><span class="plain-syntax">-></span><span class="element-syntax">hash_table</span><span class="plain-syntax">[</span><a href="2-dct.html#SP4" class="function-link"><span class="function-syntax">Dictionaries::hash</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">K</span><span class="plain-syntax">, </span><span class="identifier-syntax">D</span><span class="plain-syntax">-></span><span class="element-syntax">hash_table_size</span><span class="plain-syntax">)]);</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">E</span><span class="plain-syntax">; </span><span class="identifier-syntax">E</span><span class="plain-syntax"> = </span><span class="identifier-syntax">E</span><span class="plain-syntax">-></span><span class="element-syntax">next_in_entry</span><span class="plain-syntax">) {</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">last_E</span><span class="plain-syntax"> = </span><span class="identifier-syntax">E</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">E</span><span class="plain-syntax">-></span><span class="element-syntax">vacant</span><span class="plain-syntax">) {</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">change</span><span class="plain-syntax"> == </span><span class="constant-syntax">1</span><span class="plain-syntax">) { </span><span class="named-paragraph-container code-font"><a href="2-dct.html#SP7_3_1" class="named-paragraph-link"><span class="named-paragraph">Make E the new entry</span><span class="named-paragraph-number">7.3.1</span></a></span><span class="plain-syntax">; </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">E</span><span class="plain-syntax">; }</span>
|
|
<span class="plain-syntax"> } </span><span class="reserved-syntax">else</span><span class="plain-syntax"> {</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><a href="4-sm.html#SP19" class="function-link"><span class="function-syntax">Str::eq</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">K</span><span class="plain-syntax">, </span><span class="identifier-syntax">E</span><span class="plain-syntax">-></span><span class="element-syntax">key</span><span class="plain-syntax">)) {</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">change</span><span class="plain-syntax"> == -1) </span><span class="named-paragraph-container code-font"><a href="2-dct.html#SP7_3_2" class="named-paragraph-link"><span class="named-paragraph">Destroy the E entry</span><span class="named-paragraph-number">7.3.2</span></a></span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">E</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> }</span>
|
|
<span class="plain-syntax"> }</span>
|
|
<span class="plain-syntax"> }</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">change</span><span class="plain-syntax"> == </span><span class="constant-syntax">1</span><span class="plain-syntax">) {</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">dict_entry</span><span class="plain-syntax"> *</span><span class="identifier-syntax">E</span><span class="plain-syntax"> = </span><span class="identifier-syntax">CREATE</span><span class="plain-syntax">(</span><span class="reserved-syntax">dict_entry</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="named-paragraph-container code-font"><a href="2-dct.html#SP7_3_1" class="named-paragraph-link"><span class="named-paragraph">Make E the new entry</span><span class="named-paragraph-number">7.3.1</span></a></span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">last_E</span><span class="plain-syntax">-></span><span class="element-syntax">next_in_entry</span><span class="plain-syntax"> = </span><span class="identifier-syntax">E</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">E</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> }</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">;</span>
|
|
</pre>
|
|
<ul class="endnotetexts"><li>This code is used in <a href="2-dct.html#SP7">§7</a>.</li></ul>
|
|
<p class="commentary firstcommentary"><a id="SP7_3_1"></a><b>§7.3.1. </b>When creating text values, we want them to be empty strings rather than null
|
|
strings, so that printing to them will work.
|
|
</p>
|
|
|
|
<p class="commentary"><span class="named-paragraph-container code-font"><span class="named-paragraph-defn">Make E the new entry</span><span class="named-paragraph-number">7.3.1</span></span><span class="comment-syntax"> =</span>
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</p>
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<pre class="displayed-code all-displayed-code code-font">
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<span class="plain-syntax"> </span><span class="identifier-syntax">E</span><span class="plain-syntax">-></span><span class="element-syntax">vacant</span><span class="plain-syntax"> = </span><span class="constant-syntax">FALSE</span><span class="plain-syntax">;</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">D</span><span class="plain-syntax">-></span><span class="identifier-syntax">textual</span><span class="plain-syntax">) </span><span class="identifier-syntax">E</span><span class="plain-syntax">-></span><span class="element-syntax">value</span><span class="plain-syntax"> = </span><a href="4-sm.html#SP2" class="function-link"><span class="function-syntax">Str::new</span></a><span class="plain-syntax">(); </span><span class="reserved-syntax">else</span><span class="plain-syntax"> </span><span class="identifier-syntax">E</span><span class="plain-syntax">-></span><span class="element-syntax">value</span><span class="plain-syntax"> = </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">;</span>
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<span class="plain-syntax"> </span><span class="identifier-syntax">E</span><span class="plain-syntax">-></span><span class="element-syntax">key</span><span class="plain-syntax"> = </span><a href="4-sm.html#SP3" class="function-link"><span class="function-syntax">Str::duplicate</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">K</span><span class="plain-syntax">);</span>
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<span class="plain-syntax"> </span><span class="identifier-syntax">D</span><span class="plain-syntax">-></span><span class="element-syntax">no_entries</span><span class="plain-syntax">++;</span>
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</pre>
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<ul class="endnotetexts"><li>This code is used in <a href="2-dct.html#SP7_3">§7.3</a> (twice).</li></ul>
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<p class="commentary firstcommentary"><a id="SP7_3_2"></a><b>§7.3.2. </b>When deleting text values, we close them first, to give back the memory.
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Careful: it would not be thread-safe to allow different threads to use the
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same dictionary if deletions are a possibility.
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</p>
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<p class="commentary"><span class="named-paragraph-container code-font"><span class="named-paragraph-defn">Destroy the E entry</span><span class="named-paragraph-number">7.3.2</span></span><span class="comment-syntax"> =</span>
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</p>
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<pre class="displayed-code all-displayed-code code-font">
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<span class="plain-syntax"> </span><span class="identifier-syntax">E</span><span class="plain-syntax">-></span><span class="element-syntax">vacant</span><span class="plain-syntax"> = </span><span class="constant-syntax">TRUE</span><span class="plain-syntax">; </span><span class="identifier-syntax">D</span><span class="plain-syntax">-></span><span class="element-syntax">no_entries</span><span class="plain-syntax">--;</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> ((</span><span class="identifier-syntax">D</span><span class="plain-syntax">-></span><span class="element-syntax">textual</span><span class="plain-syntax">) && (</span><span class="identifier-syntax">E</span><span class="plain-syntax">-></span><span class="element-syntax">value</span><span class="plain-syntax">)) </span><a href="4-sm.html#SP2" class="function-link"><span class="function-syntax">Str::dispose_of</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">E</span><span class="plain-syntax">-></span><span class="element-syntax">value</span><span class="plain-syntax">);</span>
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<span class="plain-syntax"> </span><span class="identifier-syntax">E</span><span class="plain-syntax">-></span><span class="element-syntax">value</span><span class="plain-syntax"> = </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">;</span>
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</pre>
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<ul class="endnotetexts"><li>This code is used in <a href="2-dct.html#SP7_3">§7.3</a>.</li></ul>
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<p class="commentary firstcommentary"><a id="SP8"></a><b>§8. Accessing entries. </b>Eventually we're going to want the value. In principle we could be storing
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values which are arbitrary pointers, so we have to use void pointers:
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</p>
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<pre class="displayed-code all-displayed-code code-font">
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<span class="reserved-syntax">void</span><span class="plain-syntax"> *</span><span class="function-syntax">Dictionaries::read_value</span><button class="popup" onclick="togglePopup('usagePopup9')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup9">Usage of <span class="code-font"><span class="function-syntax">Dictionaries::read_value</span></span>:<br/>Command Line Arguments - <a href="3-cla.html#SP13">§13</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">dictionary</span><span class="plain-syntax"> *</span><span class="identifier-syntax">D</span><span class="plain-syntax">, </span><span class="reserved-syntax">text_stream</span><span class="plain-syntax"> *</span><span class="identifier-syntax">key</span><span class="plain-syntax">) {</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">D</span><span class="plain-syntax"> == </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">) </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">;</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">D</span><span class="plain-syntax">-></span><span class="identifier-syntax">textual</span><span class="plain-syntax">) </span><span class="identifier-syntax">internal_error</span><span class="plain-syntax">(</span><span class="string-syntax">"textual dictionary accessed as pointy"</span><span class="plain-syntax">);</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">dict_entry</span><span class="plain-syntax"> *</span><span class="identifier-syntax">E</span><span class="plain-syntax"> = </span><a href="2-dct.html#SP5" class="function-link"><span class="function-syntax">Dictionaries::find</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">D</span><span class="plain-syntax">, </span><span class="identifier-syntax">key</span><span class="plain-syntax">);</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">E</span><span class="plain-syntax"> == </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">) </span><span class="identifier-syntax">internal_error</span><span class="plain-syntax">(</span><span class="string-syntax">"read null dictionary entry"</span><span class="plain-syntax">);</span>
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|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">E</span><span class="plain-syntax">-></span><span class="identifier-syntax">vacant</span><span class="plain-syntax">) </span><span class="identifier-syntax">internal_error</span><span class="plain-syntax">(</span><span class="string-syntax">"read vacant dictionary entry"</span><span class="plain-syntax">);</span>
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|
<span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">E</span><span class="plain-syntax">-></span><span class="element-syntax">value</span><span class="plain-syntax">;</span>
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|
<span class="plain-syntax">}</span>
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|
<span class="reserved-syntax">void</span><span class="plain-syntax"> *</span><span class="function-syntax">Dictionaries::read_value_literal</span><span class="plain-syntax">(</span><span class="reserved-syntax">dictionary</span><span class="plain-syntax"> *</span><span class="identifier-syntax">D</span><span class="plain-syntax">, </span><span class="identifier-syntax">wchar_t</span><span class="plain-syntax"> *</span><span class="identifier-syntax">key</span><span class="plain-syntax">) {</span>
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|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">D</span><span class="plain-syntax"> == </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">) </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">D</span><span class="plain-syntax">-></span><span class="identifier-syntax">textual</span><span class="plain-syntax">) </span><span class="identifier-syntax">internal_error</span><span class="plain-syntax">(</span><span class="string-syntax">"textual dictionary accessed as pointy"</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">dict_entry</span><span class="plain-syntax"> *</span><span class="identifier-syntax">E</span><span class="plain-syntax"> = </span><a href="2-dct.html#SP6" class="function-link"><span class="function-syntax">Dictionaries::find_literal</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">D</span><span class="plain-syntax">, </span><span class="identifier-syntax">key</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">E</span><span class="plain-syntax"> == </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">) </span><span class="identifier-syntax">internal_error</span><span class="plain-syntax">(</span><span class="string-syntax">"read null dictionary entry"</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">E</span><span class="plain-syntax">-></span><span class="identifier-syntax">vacant</span><span class="plain-syntax">) </span><span class="identifier-syntax">internal_error</span><span class="plain-syntax">(</span><span class="string-syntax">"read vacant dictionary entry"</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">E</span><span class="plain-syntax">-></span><span class="element-syntax">value</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax">}</span>
|
|
|
|
<span class="reserved-syntax">void</span><span class="plain-syntax"> </span><span class="function-syntax">Dictionaries::write_value</span><button class="popup" onclick="togglePopup('usagePopup10')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup10">Usage of <span class="code-font"><span class="function-syntax">Dictionaries::write_value</span></span>:<br/>Command Line Arguments - <a href="3-cla.html#SP5">§5</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">dictionary</span><span class="plain-syntax"> *</span><span class="identifier-syntax">D</span><span class="plain-syntax">, </span><span class="reserved-syntax">text_stream</span><span class="plain-syntax"> *</span><span class="identifier-syntax">key</span><span class="plain-syntax">, </span><span class="reserved-syntax">void</span><span class="plain-syntax"> *</span><span class="identifier-syntax">val</span><span class="plain-syntax">) {</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">D</span><span class="plain-syntax"> == </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">) </span><span class="identifier-syntax">internal_error</span><span class="plain-syntax">(</span><span class="string-syntax">"wrote to null dictionary"</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">D</span><span class="plain-syntax">-></span><span class="identifier-syntax">textual</span><span class="plain-syntax">) </span><span class="identifier-syntax">internal_error</span><span class="plain-syntax">(</span><span class="string-syntax">"textual dictionary accessed as pointy"</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">dict_entry</span><span class="plain-syntax"> *</span><span class="identifier-syntax">E</span><span class="plain-syntax"> = </span><a href="2-dct.html#SP5" class="function-link"><span class="function-syntax">Dictionaries::find</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">D</span><span class="plain-syntax">, </span><span class="identifier-syntax">key</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">E</span><span class="plain-syntax"> == </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">) </span><span class="identifier-syntax">internal_error</span><span class="plain-syntax">(</span><span class="string-syntax">"wrote null dictionary entry"</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">E</span><span class="plain-syntax">-></span><span class="identifier-syntax">vacant</span><span class="plain-syntax">) </span><span class="identifier-syntax">internal_error</span><span class="plain-syntax">(</span><span class="string-syntax">"wrote vacant dictionary entry"</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">E</span><span class="plain-syntax">-></span><span class="element-syntax">value</span><span class="plain-syntax"> = </span><span class="identifier-syntax">val</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax">}</span>
|
|
<span class="reserved-syntax">void</span><span class="plain-syntax"> </span><span class="function-syntax">Dictionaries::write_value_literal</span><span class="plain-syntax">(</span><span class="reserved-syntax">dictionary</span><span class="plain-syntax"> *</span><span class="identifier-syntax">D</span><span class="plain-syntax">, </span><span class="identifier-syntax">wchar_t</span><span class="plain-syntax"> *</span><span class="identifier-syntax">key</span><span class="plain-syntax">, </span><span class="reserved-syntax">void</span><span class="plain-syntax"> *</span><span class="identifier-syntax">val</span><span class="plain-syntax">) {</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">D</span><span class="plain-syntax"> == </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">) </span><span class="identifier-syntax">internal_error</span><span class="plain-syntax">(</span><span class="string-syntax">"wrote to null dictionary"</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">D</span><span class="plain-syntax">-></span><span class="identifier-syntax">textual</span><span class="plain-syntax">) </span><span class="identifier-syntax">internal_error</span><span class="plain-syntax">(</span><span class="string-syntax">"textual dictionary accessed as pointy"</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">dict_entry</span><span class="plain-syntax"> *</span><span class="identifier-syntax">E</span><span class="plain-syntax"> = </span><a href="2-dct.html#SP6" class="function-link"><span class="function-syntax">Dictionaries::find_literal</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">D</span><span class="plain-syntax">, </span><span class="identifier-syntax">key</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">E</span><span class="plain-syntax"> == </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">) </span><span class="identifier-syntax">internal_error</span><span class="plain-syntax">(</span><span class="string-syntax">"wrote null dictionary entry"</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">E</span><span class="plain-syntax">-></span><span class="identifier-syntax">vacant</span><span class="plain-syntax">) </span><span class="identifier-syntax">internal_error</span><span class="plain-syntax">(</span><span class="string-syntax">"wrote vacant dictionary entry"</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">E</span><span class="plain-syntax">-></span><span class="element-syntax">value</span><span class="plain-syntax"> = </span><span class="identifier-syntax">val</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax">}</span>
|
|
</pre>
|
|
<p class="commentary firstcommentary"><a id="SP9"></a><b>§9. </b>But the commonest use case is that the dictionary stores texts as values,
|
|
so we provide convenient wrappers with the correct C types.
|
|
</p>
|
|
|
|
<pre class="displayed-code all-displayed-code code-font">
|
|
<span class="reserved-syntax">text_stream</span><span class="plain-syntax"> *</span><span class="function-syntax">Dictionaries::create_text</span><span class="plain-syntax">(</span><span class="reserved-syntax">dictionary</span><span class="plain-syntax"> *</span><span class="identifier-syntax">D</span><span class="plain-syntax">, </span><span class="reserved-syntax">text_stream</span><span class="plain-syntax"> *</span><span class="identifier-syntax">key</span><span class="plain-syntax">) {</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">D</span><span class="plain-syntax"> == </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">) </span><span class="identifier-syntax">internal_error</span><span class="plain-syntax">(</span><span class="string-syntax">"wrote to null dictionary"</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">D</span><span class="plain-syntax">-></span><span class="identifier-syntax">textual</span><span class="plain-syntax"> == </span><span class="constant-syntax">FALSE</span><span class="plain-syntax">) </span><span class="identifier-syntax">internal_error</span><span class="plain-syntax">(</span><span class="string-syntax">"pointy dictionary accessed as textual"</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">dict_entry</span><span class="plain-syntax"> *</span><span class="identifier-syntax">E</span><span class="plain-syntax"> = </span><a href="2-dct.html#SP5" class="function-link"><span class="function-syntax">Dictionaries::create</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">D</span><span class="plain-syntax">, </span><span class="identifier-syntax">key</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax"> (</span><span class="reserved-syntax">text_stream</span><span class="plain-syntax"> *) </span><span class="identifier-syntax">E</span><span class="plain-syntax">-></span><span class="element-syntax">value</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax">}</span>
|
|
<span class="reserved-syntax">text_stream</span><span class="plain-syntax"> *</span><span class="function-syntax">Dictionaries::create_text_literal</span><span class="plain-syntax">(</span><span class="reserved-syntax">dictionary</span><span class="plain-syntax"> *</span><span class="identifier-syntax">D</span><span class="plain-syntax">, </span><span class="identifier-syntax">wchar_t</span><span class="plain-syntax"> *</span><span class="identifier-syntax">lit</span><span class="plain-syntax">) {</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">D</span><span class="plain-syntax"> == </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">) </span><span class="identifier-syntax">internal_error</span><span class="plain-syntax">(</span><span class="string-syntax">"wrote to null dictionary"</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">D</span><span class="plain-syntax">-></span><span class="identifier-syntax">textual</span><span class="plain-syntax"> == </span><span class="constant-syntax">FALSE</span><span class="plain-syntax">) </span><span class="identifier-syntax">internal_error</span><span class="plain-syntax">(</span><span class="string-syntax">"pointy dictionary accessed as textual"</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">dict_entry</span><span class="plain-syntax"> *</span><span class="identifier-syntax">E</span><span class="plain-syntax"> = </span><a href="2-dct.html#SP6" class="function-link"><span class="function-syntax">Dictionaries::create_literal</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">D</span><span class="plain-syntax">, </span><span class="identifier-syntax">lit</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax"> (</span><span class="reserved-syntax">text_stream</span><span class="plain-syntax"> *) </span><span class="identifier-syntax">E</span><span class="plain-syntax">-></span><span class="element-syntax">value</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax">}</span>
|
|
</pre>
|
|
<p class="commentary firstcommentary"><a id="SP10"></a><b>§10. </b>We only need a read operation, because the caller can write to the dictionary
|
|
entry by reading the text pointer and then using <span class="extract"><span class="extract-syntax">WRITE_TO</span></span>.
|
|
</p>
|
|
|
|
<pre class="displayed-code all-displayed-code code-font">
|
|
<span class="reserved-syntax">text_stream</span><span class="plain-syntax"> *</span><span class="function-syntax">Dictionaries::get_text</span><span class="plain-syntax">(</span><span class="reserved-syntax">dictionary</span><span class="plain-syntax"> *</span><span class="identifier-syntax">D</span><span class="plain-syntax">, </span><span class="reserved-syntax">text_stream</span><span class="plain-syntax"> *</span><span class="identifier-syntax">key</span><span class="plain-syntax">) {</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">D</span><span class="plain-syntax"> == </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">) </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">D</span><span class="plain-syntax">-></span><span class="identifier-syntax">textual</span><span class="plain-syntax"> == </span><span class="constant-syntax">FALSE</span><span class="plain-syntax">) </span><span class="identifier-syntax">internal_error</span><span class="plain-syntax">(</span><span class="string-syntax">"pointy dictionary accessed as textual"</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">dict_entry</span><span class="plain-syntax"> *</span><span class="identifier-syntax">E</span><span class="plain-syntax"> = </span><a href="2-dct.html#SP5" class="function-link"><span class="function-syntax">Dictionaries::find</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">D</span><span class="plain-syntax">, </span><span class="identifier-syntax">key</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">E</span><span class="plain-syntax"> == </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">) </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">;</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax"> (</span><span class="reserved-syntax">text_stream</span><span class="plain-syntax"> *) </span><span class="identifier-syntax">E</span><span class="plain-syntax">-></span><span class="element-syntax">value</span><span class="plain-syntax">;</span>
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<span class="plain-syntax">}</span>
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<span class="reserved-syntax">text_stream</span><span class="plain-syntax"> *</span><span class="function-syntax">Dictionaries::get_text_literal</span><button class="popup" onclick="togglePopup('usagePopup11')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup11">Usage of <span class="code-font"><span class="function-syntax">Dictionaries::get_text_literal</span></span>:<br/>String Manipulation - <a href="4-sm.html#SP27_1">§27.1</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">dictionary</span><span class="plain-syntax"> *</span><span class="identifier-syntax">D</span><span class="plain-syntax">, </span><span class="identifier-syntax">wchar_t</span><span class="plain-syntax"> *</span><span class="identifier-syntax">lit</span><span class="plain-syntax">) {</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">D</span><span class="plain-syntax"> == </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">) </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">;</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">D</span><span class="plain-syntax">-></span><span class="identifier-syntax">textual</span><span class="plain-syntax"> == </span><span class="constant-syntax">FALSE</span><span class="plain-syntax">) </span><span class="identifier-syntax">internal_error</span><span class="plain-syntax">(</span><span class="string-syntax">"pointy dictionary accessed as textual"</span><span class="plain-syntax">);</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">dict_entry</span><span class="plain-syntax"> *</span><span class="identifier-syntax">E</span><span class="plain-syntax"> = </span><a href="2-dct.html#SP6" class="function-link"><span class="function-syntax">Dictionaries::find_literal</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">D</span><span class="plain-syntax">, </span><span class="identifier-syntax">lit</span><span class="plain-syntax">);</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">E</span><span class="plain-syntax"> == </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">) </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">;</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax"> (</span><span class="reserved-syntax">text_stream</span><span class="plain-syntax"> *) </span><span class="identifier-syntax">E</span><span class="plain-syntax">-></span><span class="element-syntax">value</span><span class="plain-syntax">;</span>
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<span class="plain-syntax">}</span>
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</pre>
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<p class="commentary firstcommentary"><a id="SP11"></a><b>§11. Disposal. </b>If a dictionary was only needed temporarily then we should dispose of it
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and free the memory when done:
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</p>
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<pre class="displayed-code all-displayed-code code-font">
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<span class="reserved-syntax">void</span><span class="plain-syntax"> </span><span class="function-syntax">Dictionaries::dispose_of</span><span class="plain-syntax">(</span><span class="reserved-syntax">dictionary</span><span class="plain-syntax"> *</span><span class="identifier-syntax">D</span><span class="plain-syntax">) {</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">D</span><span class="plain-syntax">-></span><span class="identifier-syntax">textual</span><span class="plain-syntax">)</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">for</span><span class="plain-syntax"> (</span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">i</span><span class="plain-syntax">=0; </span><span class="identifier-syntax">i</span><span class="function-syntax"><D-></span><span class="element-syntax">hash_table_size</span><span class="plain-syntax">; </span><span class="identifier-syntax">i</span><span class="plain-syntax">++)</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">for</span><span class="plain-syntax"> (</span><span class="reserved-syntax">dict_entry</span><span class="plain-syntax"> *</span><span class="identifier-syntax">E</span><span class="plain-syntax"> = &(</span><span class="identifier-syntax">D</span><span class="plain-syntax">-></span><span class="element-syntax">hash_table</span><span class="plain-syntax">[</span><span class="identifier-syntax">i</span><span class="plain-syntax">]); </span><span class="identifier-syntax">E</span><span class="plain-syntax">; </span><span class="identifier-syntax">E</span><span class="plain-syntax"> = </span><span class="identifier-syntax">E</span><span class="plain-syntax">-></span><span class="element-syntax">next_in_entry</span><span class="plain-syntax">)</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">E</span><span class="plain-syntax">-></span><span class="element-syntax">vacant</span><span class="plain-syntax"> == </span><span class="constant-syntax">FALSE</span><span class="plain-syntax">)</span>
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<span class="plain-syntax"> </span><a href="4-sm.html#SP2" class="function-link"><span class="function-syntax">Str::dispose_of</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">E</span><span class="plain-syntax">-></span><span class="element-syntax">value</span><span class="plain-syntax">);</span>
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<span class="plain-syntax"> </span><a href="2-mmr.html#SP26" class="function-link"><span class="function-syntax">Memory::I7_free</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">D</span><span class="plain-syntax">-></span><span class="element-syntax">hash_table</span><span class="plain-syntax">, </span><span class="constant-syntax">DICTIONARY_MREASON</span><span class="plain-syntax">, </span><span class="identifier-syntax">D</span><span class="plain-syntax">-></span><span class="element-syntax">hash_table_size</span><span class="plain-syntax">*((</span><span class="reserved-syntax">int</span><span class="plain-syntax">) </span><span class="reserved-syntax">sizeof</span><span class="plain-syntax">(</span><span class="reserved-syntax">dict_entry</span><span class="plain-syntax">)));</span>
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<span class="plain-syntax"> </span><span class="identifier-syntax">D</span><span class="plain-syntax">-></span><span class="element-syntax">hash_table</span><span class="plain-syntax"> = </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">;</span>
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<span class="plain-syntax">}</span>
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</pre>
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