ifhub/inform7
1
0
Fork 0
mirror of https://github.com/ganelson/inform.git synced 2024-07-05 08:34:22 +03:00
Code Issues Projects Releases Wiki Activity
inform7/docs/if-module/5-gt.html
Graham Nelson 43bbcdbaf4 Completed assertions module
2021-02-05 00:15:21 +00:00

209 lines
35 KiB
HTML
Raw Blame History

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<title>Grammar Types</title>
<link href="../docs-assets/Breadcrumbs.css" rel="stylesheet" rev="stylesheet" type="text/css">
<meta name="viewport" content="width=device-width initial-scale=1">
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<meta http-equiv="Content-Language" content="en-gb">
<link href="../docs-assets/Contents.css" rel="stylesheet" rev="stylesheet" type="text/css">
<link href="../docs-assets/Progress.css" rel="stylesheet" rev="stylesheet" type="text/css">
<link href="../docs-assets/Navigation.css" rel="stylesheet" rev="stylesheet" type="text/css">
<link href="../docs-assets/Fonts.css" rel="stylesheet" rev="stylesheet" type="text/css">
<link href="../docs-assets/Base.css" rel="stylesheet" rev="stylesheet" type="text/css">
<script>
function togglePopup(material_id) {
var popup = document.getElementById(material_id);
popup.classList.toggle("show");
}
</script>
<link href="../docs-assets/Popups.css" rel="stylesheet" rev="stylesheet" type="text/css">
<link href="../docs-assets/Colours.css" rel="stylesheet" rev="stylesheet" type="text/css">
</head>
<body class="commentary-font">
<nav role="navigation">
<h1><a href="../index.html">
<img src="../docs-assets/Inform.png" height=72">
</a></h1>
<ul><li><a href="../compiler.html">compiler tools</a></li>
<li><a href="../other.html">other tools</a></li>
<li><a href="../extensions.html">extensions and kits</a></li>
<li><a href="../units.html">unit test tools</a></li>
</ul><h2>Compiler Webs</h2><ul>
<li><a href="../inbuild/index.html">inbuild</a></li>
<li><a href="../inform7/index.html">inform7</a></li>
<li><a href="../inter/index.html">inter</a></li>
</ul><h2>Inbuild Modules</h2><ul>
<li><a href="../supervisor-module/index.html">supervisor</a></li>
</ul><h2>Inform7 Modules</h2><ul>
<li><a href="../core-module/index.html">core</a></li>
<li><a href="../assertions-module/index.html">assertions</a></li>
<li><a href="../values-module/index.html">values</a></li>
<li><a href="../knowledge-module/index.html">knowledge</a></li>
<li><a href="../imperative-module/index.html">imperative</a></li>
<li><a href="../runtime-module/index.html">runtime</a></li>
<li><a href="index.html"><span class="selectedlink">if</span></a></li>
<li><a href="../multimedia-module/index.html">multimedia</a></li>
<li><a href="../index-module/index.html">index</a></li>
</ul><h2>Inter Modules</h2><ul>
<li><a href="../bytecode-module/index.html">bytecode</a></li>
<li><a href="../building-module/index.html">building</a></li>
<li><a href="../codegen-module/index.html">codegen</a></li>
</ul><h2>Services</h2><ul>
<li><a href="../arch-module/index.html">arch</a></li>
<li><a href="../calculus-module/index.html">calculus</a></li>
<li><a href="../html-module/index.html">html</a></li>
<li><a href="../inflections-module/index.html">inflections</a></li>
<li><a href="../kinds-module/index.html">kinds</a></li>
<li><a href="../linguistics-module/index.html">linguistics</a></li>
<li><a href="../problems-module/index.html">problems</a></li>
<li><a href="../syntax-module/index.html">syntax</a></li>
<li><a href="../words-module/index.html">words</a></li>
<li><a href="../../../inweb/docs/foundation-module/index.html">foundation</a></li>
</ul>
</nav>
<main role="main">
<!--Weave of 'Grammar Types' generated by Inweb-->
<div class="breadcrumbs">
<ul class="crumbs"><li><a href="../index.html">Home</a></li><li><a href="../compiler.html">Inform7</a></li><li><a href="index.html">if</a></li><li><a href="index.html#5">Chapter 5: Command Grammar</a></li><li><b>Grammar Types</b></li></ul></div>
<p class="purpose">Some grammar text specifies one or more values, and we need to keep track of their kind(s). Here we manage the data structure doing this.</p>
<ul class="toc"><li><a href="5-gt.html#SP1">&#167;1. Definitions</a></li></ul><hr class="tocbar">
<p class="commentary firstcommentary"><a id="SP1" class="paragraph-anchor"></a><b>&#167;1. Definitions. </b></p>
<pre class="displayed-code all-displayed-code code-font">
<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">grammar_type</span><span class="plain-syntax"> {</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">no_resulting_values</span><span class="plain-syntax">; </span><span class="comment-syntax"> number of resulting values: 0, 1 or 2; or </span><span class="extract"><span class="extract-syntax">-1</span></span>
<span class="plain-syntax"> </span><span class="reserved-syntax">struct</span><span class="plain-syntax"> </span><span class="identifier-syntax">parse_node</span><span class="plain-syntax"> *</span><span class="identifier-syntax">first_type</span><span class="plain-syntax">; </span><span class="comment-syntax"> and their types</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">struct</span><span class="plain-syntax"> </span><span class="identifier-syntax">parse_node</span><span class="plain-syntax"> *</span><span class="identifier-syntax">second_type</span><span class="plain-syntax">;</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">first_multiplicity</span><span class="plain-syntax">; </span><span class="comment-syntax"> lines only: allow a multiple object here?</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">second_multiplicity</span><span class="plain-syntax">; </span><span class="comment-syntax"> lines only: allow a multiple object here?</span>
<span class="plain-syntax">} </span><span class="reserved-syntax">grammar_type</span><span class="plain-syntax">;</span>
</pre>
<ul class="endnotetexts"><li>The structure grammar_type is private to this section.</li></ul>
<p class="commentary firstcommentary"><a id="SP2" class="paragraph-anchor"></a><b>&#167;2. </b></p>
<pre class="displayed-code all-displayed-code code-font">
<span class="reserved-syntax">grammar_type</span><span class="plain-syntax"> </span><span class="function-syntax">PL::Parsing::Tokens::Types::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">PL::Parsing::Tokens::Types::new</span></span>:<br/>Grammar Verbs - <a href="5-gv.html#SP4">&#167;4</a><br/>Grammar Lines - <a href="5-gl.html#SP3">&#167;3</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">supports_return_type</span><span class="plain-syntax">) {</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">grammar_type</span><span class="plain-syntax"> </span><span class="identifier-syntax">gty</span><span class="plain-syntax">;</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">gty</span><span class="plain-syntax">.</span><span class="element-syntax">first_type</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">gty</span><span class="plain-syntax">.</span><span class="element-syntax">second_type</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">gty</span><span class="plain-syntax">.</span><span class="element-syntax">first_multiplicity</span><span class="plain-syntax"> = </span><span class="identifier-syntax">FALSE</span><span class="plain-syntax">;</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">gty</span><span class="plain-syntax">.</span><span class="element-syntax">second_multiplicity</span><span class="plain-syntax"> = </span><span class="identifier-syntax">FALSE</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">supports_return_type</span><span class="plain-syntax">)</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">gty</span><span class="plain-syntax">.</span><span class="element-syntax">no_resulting_values</span><span class="plain-syntax"> = </span><span class="constant-syntax">0</span><span class="plain-syntax">;</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">else</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">gty</span><span class="plain-syntax">.</span><span class="element-syntax">no_resulting_values</span><span class="plain-syntax"> = -1;</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">gty</span><span class="plain-syntax">;</span>
<span class="plain-syntax">}</span>
</pre>
<p class="commentary firstcommentary"><a id="SP3" class="paragraph-anchor"></a><b>&#167;3. </b>The multiplication by 10 here is explained in the discussion of GSB
tallying during GL sorting in "Grammar Lines". Do not amend it without
changing that discussion.
</p>
<pre class="displayed-code all-displayed-code code-font">
<span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="function-syntax">PL::Parsing::Tokens::Types::add_type</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">PL::Parsing::Tokens::Types::add_type</span></span>:<br/>Grammar Lines - <a href="5-gl.html#SP14">&#167;14</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">grammar_type</span><span class="plain-syntax"> *</span><span class="identifier-syntax">gty</span><span class="plain-syntax">, </span><span class="identifier-syntax">parse_node</span><span class="plain-syntax"> *</span><span class="identifier-syntax">spec</span><span class="plain-syntax">,</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">multiple_flag</span><span class="plain-syntax">, </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">score</span><span class="plain-syntax">) {</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">switch</span><span class="plain-syntax">((</span><span class="identifier-syntax">gty</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">no_resulting_values</span><span class="plain-syntax">)++) {</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">case</span><span class="plain-syntax"> </span><span class="constant-syntax">0</span><span class="plain-syntax">:</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">gty</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">first_type</span><span class="plain-syntax"> = </span><span class="identifier-syntax">spec</span><span class="plain-syntax">;</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">gty</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">first_multiplicity</span><span class="plain-syntax"> = </span><span class="identifier-syntax">multiple_flag</span><span class="plain-syntax">;</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="constant-syntax">10</span><span class="plain-syntax">*</span><span class="identifier-syntax">score</span><span class="plain-syntax">;</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">case</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">gty</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">second_type</span><span class="plain-syntax"> = </span><span class="identifier-syntax">spec</span><span class="plain-syntax">;</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">gty</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">second_multiplicity</span><span class="plain-syntax"> = </span><span class="identifier-syntax">multiple_flag</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">score</span><span class="plain-syntax">;</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">case</span><span class="plain-syntax"> </span><span class="constant-syntax">2</span><span class="plain-syntax">:</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">StandardProblems::sentence_problem</span><span class="plain-syntax">(</span><span class="identifier-syntax">Task::syntax_tree</span><span class="plain-syntax">(), </span><span class="identifier-syntax">_p_</span><span class="plain-syntax">(</span><span class="identifier-syntax">PM_ThreeValuedLine</span><span class="plain-syntax">),</span>
<span class="plain-syntax"> </span><span class="string-syntax">"there can be at most two varying parts to a line of grammar"</span><span class="plain-syntax">,</span>
<span class="plain-syntax"> </span><span class="string-syntax">"so 'put [something] in [a container]' is allowed but 'put "</span>
<span class="plain-syntax"> </span><span class="string-syntax">"[something] in [something] beside [a door]' is not."</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="constant-syntax">0</span><span class="plain-syntax">;</span>
<span class="plain-syntax">}</span>
<span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="function-syntax">PL::Parsing::Tokens::Types::has_return_type</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">PL::Parsing::Tokens::Types::has_return_type</span></span>:<br/>Grammar Verbs - <a href="5-gv.html#SP24">&#167;24</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">grammar_type</span><span class="plain-syntax"> *</span><span class="identifier-syntax">gty</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">gty</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">no_resulting_values</span><span class="plain-syntax"> == -1) </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">FALSE</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">TRUE</span><span class="plain-syntax">;</span>
<span class="plain-syntax">}</span>
<span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="function-syntax">PL::Parsing::Tokens::Types::get_no_resulting_values</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">PL::Parsing::Tokens::Types::get_no_resulting_values</span></span>:<br/>Grammar Lines - <a href="5-gl.html#SP14">&#167;14</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">grammar_type</span><span class="plain-syntax"> *</span><span class="identifier-syntax">gty</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">gty</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">no_resulting_values</span><span class="plain-syntax">;</span>
<span class="plain-syntax">}</span>
<span class="identifier-syntax">parse_node</span><span class="plain-syntax"> *</span><span class="function-syntax">PL::Parsing::Tokens::Types::get_single_type</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">PL::Parsing::Tokens::Types::get_single_type</span></span>:<br/>Grammar Verbs - <a href="5-gv.html#SP24">&#167;24</a><br/>Grammar Lines - <a href="5-gl.html#SP14">&#167;14</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">grammar_type</span><span class="plain-syntax"> *</span><span class="identifier-syntax">gty</span><span class="plain-syntax">) {</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">switch</span><span class="plain-syntax">(</span><span class="identifier-syntax">gty</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">no_resulting_values</span><span class="plain-syntax">) {</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">case</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="reserved-syntax">case</span><span class="plain-syntax"> </span><span class="constant-syntax">1</span><span class="plain-syntax">: </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">gty</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">first_type</span><span class="plain-syntax">;</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">default:</span><span class="plain-syntax"> </span><span class="identifier-syntax">internal_error</span><span class="plain-syntax">(</span><span class="string-syntax">"gty improperly typed"</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>
<span class="plain-syntax">}</span>
<span class="reserved-syntax">void</span><span class="plain-syntax"> </span><span class="function-syntax">PL::Parsing::Tokens::Types::set_single_type</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">PL::Parsing::Tokens::Types::set_single_type</span></span>:<br/>Grammar Verbs - <a href="5-gv.html#SP24">&#167;24</a><br/>Grammar Lines - <a href="5-gl.html#SP3">&#167;3</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">grammar_type</span><span class="plain-syntax"> *</span><span class="identifier-syntax">gty</span><span class="plain-syntax">, </span><span class="identifier-syntax">parse_node</span><span class="plain-syntax"> *</span><span class="identifier-syntax">spec</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">spec</span><span class="plain-syntax"> == </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">) </span><span class="identifier-syntax">gty</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">no_resulting_values</span><span class="plain-syntax"> = </span><span class="constant-syntax">0</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="identifier-syntax">gty</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">no_resulting_values</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">gty</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">first_type</span><span class="plain-syntax"> = </span><span class="identifier-syntax">spec</span><span class="plain-syntax">;</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">PL::Parsing::Tokens::Types::compile_to_string</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">PL::Parsing::Tokens::Types::compile_to_string</span></span>:<br/>Grammar Lines - <a href="5-gl.html#SP19">&#167;19</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">grammar_type</span><span class="plain-syntax"> *</span><span class="identifier-syntax">gty</span><span class="plain-syntax">) {</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">Specifications::Compiler::emit_as_val</span><span class="plain-syntax">(</span><span class="identifier-syntax">K_value</span><span class="plain-syntax">, </span><span class="identifier-syntax">gty</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">first_type</span><span class="plain-syntax">);</span>
<span class="plain-syntax">}</span>
<span class="identifier-syntax">kind</span><span class="plain-syntax"> *</span><span class="function-syntax">PL::Parsing::Tokens::Types::get_data_type_as_token</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">PL::Parsing::Tokens::Types::get_data_type_as_token</span></span>:<br/>Grammar Verbs - <a href="5-gv.html#SP20">&#167;20</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">grammar_type</span><span class="plain-syntax"> *</span><span class="identifier-syntax">gty</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">gty</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">no_resulting_values</span><span class="plain-syntax"> &gt; </span><span class="constant-syntax">0</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">Node::is</span><span class="plain-syntax">(</span><span class="identifier-syntax">gty</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">first_type</span><span class="plain-syntax">, </span><span class="identifier-syntax">CONSTANT_NT</span><span class="plain-syntax">)) ||</span>
<span class="plain-syntax"> (</span><span class="identifier-syntax">Specifications::is_description</span><span class="plain-syntax">(</span><span class="identifier-syntax">gty</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">first_type</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">Specifications::to_kind</span><span class="plain-syntax">(</span><span class="identifier-syntax">gty</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">first_type</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>
<span class="plain-syntax">}</span>
</pre>
<p class="commentary firstcommentary"><a id="SP4" class="paragraph-anchor"></a><b>&#167;4. </b>The behaviour of this sorting routine is documented in the discussion
of GL sorting in "Grammar Lines". Do not amend it without changing that
discussion.
</p>
<pre class="displayed-code all-displayed-code code-font">
<span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="function-syntax">PL::Parsing::Tokens::Types::must_precede</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">PL::Parsing::Tokens::Types::must_precede</span></span>:<br/>Grammar Lines - <a href="5-gl.html#SP16">&#167;16</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">grammar_type</span><span class="plain-syntax"> *</span><span class="identifier-syntax">gty1</span><span class="plain-syntax">, </span><span class="reserved-syntax">grammar_type</span><span class="plain-syntax"> *</span><span class="identifier-syntax">gty2</span><span class="plain-syntax">) {</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">cs</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">gty1</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">no_resulting_values</span><span class="plain-syntax">) &lt; (</span><span class="identifier-syntax">gty2</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">no_resulting_values</span><span class="plain-syntax">)) </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">TRUE</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">gty1</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">no_resulting_values</span><span class="plain-syntax">) &gt; (</span><span class="identifier-syntax">gty2</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">no_resulting_values</span><span class="plain-syntax">)) </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">FALSE</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">gty1</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">no_resulting_values</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">NOT_APPLICABLE</span><span class="plain-syntax">;</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">cs</span><span class="plain-syntax"> = </span><span class="identifier-syntax">Specifications::compare_specificity</span><span class="plain-syntax">(</span><span class="identifier-syntax">gty1</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">first_type</span><span class="plain-syntax">, </span><span class="identifier-syntax">gty2</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">first_type</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">cs</span><span class="plain-syntax"> == </span><span class="constant-syntax">1</span><span class="plain-syntax">) </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">TRUE</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">cs</span><span class="plain-syntax"> == -1) </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">FALSE</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">gty1</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">first_multiplicity</span><span class="plain-syntax">) &amp;&amp; (</span><span class="identifier-syntax">gty2</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">first_multiplicity</span><span class="plain-syntax"> == </span><span class="identifier-syntax">FALSE</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">FALSE</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">gty1</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">first_multiplicity</span><span class="plain-syntax"> == </span><span class="identifier-syntax">FALSE</span><span class="plain-syntax">) &amp;&amp; (</span><span class="identifier-syntax">gty2</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">first_multiplicity</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">TRUE</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">gty1</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">no_resulting_values</span><span class="plain-syntax"> == </span><span class="constant-syntax">1</span><span class="plain-syntax">) </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">NOT_APPLICABLE</span><span class="plain-syntax">;</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">cs</span><span class="plain-syntax"> = </span><span class="identifier-syntax">Specifications::compare_specificity</span><span class="plain-syntax">(</span><span class="identifier-syntax">gty1</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">second_type</span><span class="plain-syntax">, </span><span class="identifier-syntax">gty2</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">second_type</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">cs</span><span class="plain-syntax"> == </span><span class="constant-syntax">1</span><span class="plain-syntax">) </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">TRUE</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">cs</span><span class="plain-syntax"> == -1) </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">FALSE</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">gty1</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">second_multiplicity</span><span class="plain-syntax">) &amp;&amp; (</span><span class="identifier-syntax">gty2</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">second_multiplicity</span><span class="plain-syntax"> == </span><span class="identifier-syntax">FALSE</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">FALSE</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">gty1</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">second_multiplicity</span><span class="plain-syntax"> == </span><span class="identifier-syntax">FALSE</span><span class="plain-syntax">) &amp;&amp; (</span><span class="identifier-syntax">gty2</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">second_multiplicity</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">TRUE</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">NOT_APPLICABLE</span><span class="plain-syntax">;</span>
<span class="plain-syntax">}</span>
</pre>
<nav role="progress"><div class="progresscontainer">
<ul class="progressbar"><li class="progressprev"><a href="5-gl.html">&#10094;</a></li><li class="progresschapter"><a href="1-im.html">1</a></li><li class="progresschapter"><a href="2-ifi.html">2</a></li><li class="progresschapter"><a href="3-tnt.html">3</a></li><li class="progresschapter"><a href="4-act.html">4</a></li><li class="progresscurrentchapter">5</li><li class="progresssection"><a href="5-itg.html">itg</a></li><li class="progresssection"><a href="5-tfg.html">tfg</a></li><li class="progresssection"><a href="5-gp.html">gp</a></li><li class="progresssection"><a href="5-gv.html">gv</a></li><li class="progresssection"><a href="5-gl.html">gl</a></li><li class="progresscurrent">gt</li><li class="progresssection"><a href="5-gt2.html">gt2</a></li><li class="progresssection"><a href="5-nft.html">nft</a></li><li class="progresssection"><a href="5-tpv.html">tpv</a></li><li class="progresssection"><a href="5-gpr.html">gpr</a></li><li class="progressnext"><a href="5-gt2.html">&#10095;</a></li></ul></div>
</nav><!--End of weave-->
</main>
</body>
</html>
Reference in a new issue View git blame Copy permalink