mirror of
https://github.com/ganelson/inform.git
synced 2024-07-16 22:14:23 +03:00
685 lines
118 KiB
HTML
685 lines
118 KiB
HTML
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
|
|
<html>
|
|
<head>
|
|
<title>Command Grammars</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">
|
|
<script src="http://code.jquery.com/jquery-1.12.4.min.js"
|
|
integrity="sha256-ZosEbRLbNQzLpnKIkEdrPv7lOy9C27hHQ+Xp8a4MxAQ=" crossorigin="anonymous"></script>
|
|
|
|
<script src="../docs-assets/Bigfoot.js"></script>
|
|
<link href="../docs-assets/Bigfoot.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="../index.html">home</a></li>
|
|
</ul><h2>Compiler</h2><ul>
|
|
<li><a href="../structure.html">structure</a></li>
|
|
<li><a href="../inbuildn.html">inbuild</a></li>
|
|
<li><a href="../inform7n.html">inform7</a></li>
|
|
<li><a href="../intern.html">inter</a></li>
|
|
<li><a href="../services.html">services</a></li>
|
|
<li><a href="../secrets.html">secrets</a></li>
|
|
</ul><h2>Other Tools</h2><ul>
|
|
<li><a href="../inblorbn.html">inblorb</a></li>
|
|
<li><a href="../indocn.html">indoc</a></li>
|
|
<li><a href="../inform6.html">inform6</a></li>
|
|
<li><a href="../inpolicyn.html">inpolicy</a></li>
|
|
<li><a href="../inrtpsn.html">inrtps</a></li>
|
|
</ul><h2>Resources</h2><ul>
|
|
<li><a href="../extensions.html">extensions</a></li>
|
|
<li><a href="../kits.html">kits</a></li>
|
|
</ul><h2>Repository</h2><ul>
|
|
<li><a href="https://github.com/ganelson/inform"><img src="../docs-assets/github.png" height=18> github</a></li>
|
|
</ul><h2>Related Projects</h2><ul>
|
|
<li><a href="../../../inweb/index.html">inweb</a></li>
|
|
<li><a href="../../../intest/index.html">intest</a></li>
|
|
|
|
</ul>
|
|
</nav>
|
|
<main role="main">
|
|
<!--Weave of 'Command Grammars' generated by Inweb-->
|
|
<div class="breadcrumbs">
|
|
<ul class="crumbs"><li><a href="../index.html">Home</a></li><li><a href="../inform7n.html">Inform7</a></li><li><a href="index.html">if</a></li><li><a href="index.html#5">Chapter 5: Command Parser</a></li><li><b>Command Grammars</b></li></ul></div>
|
|
<p class="purpose">The possible command text following a command verb, or referring to a single concept or object, is gathered into a "command grammar".</p>
|
|
|
|
<ul class="toc"><li><a href="5-cg.html#SP5">§5. The CG_IS_COMMAND form</a></li><li><a href="5-cg.html#SP11">§11. The CG_IS_TOKEN form</a></li><li><a href="5-cg.html#SP13">§13. The CG_IS_SUBJECT form</a></li><li><a href="5-cg.html#SP14">§14. The CG_IS_VALUE form</a></li><li><a href="5-cg.html#SP15">§15. The CG_IS_CONSULT form</a></li><li><a href="5-cg.html#SP16">§16. The CG_IS_PROPERTY_NAME form</a></li><li><a href="5-cg.html#SP17">§17. The list of grammar lines</a></li><li><a href="5-cg.html#SP19">§19. Slashing and determining</a></li><li><a href="5-cg.html#SP21">§21. Sorting</a></li></ul><hr class="tocbar">
|
|
|
|
<p class="commentary firstcommentary"><a id="SP1" class="paragraph-anchor"></a><b>§1. </b>Command grammars, or CGs, are used in six excitingly different ways:
|
|
</p>
|
|
|
|
<pre class="definitions code-font"><span class="definition-keyword">define</span> <span class="constant-syntax">CG_IS_COMMAND</span><span class="plain-syntax"> </span><span class="constant-syntax">1</span><span class="plain-syntax"> </span><span class="comment-syntax"> for player-typed commands starting with a given verb</span>
|
|
<span class="definition-keyword">define</span> <span class="constant-syntax">CG_IS_TOKEN</span><span class="plain-syntax"> </span><span class="constant-syntax">2</span><span class="plain-syntax"> </span><span class="comment-syntax"> for defining a square-bracketed token used in commands</span>
|
|
<span class="definition-keyword">define</span> <span class="constant-syntax">CG_IS_SUBJECT</span><span class="plain-syntax"> </span><span class="constant-syntax">3</span><span class="plain-syntax"> </span><span class="comment-syntax"> for ways the player can refer to an object or kind</span>
|
|
<span class="definition-keyword">define</span> <span class="constant-syntax">CG_IS_VALUE</span><span class="plain-syntax"> </span><span class="constant-syntax">4</span><span class="plain-syntax"> </span><span class="comment-syntax"> for ways the player can refer to a non-object value</span>
|
|
<span class="definition-keyword">define</span> <span class="constant-syntax">CG_IS_CONSULT</span><span class="plain-syntax"> </span><span class="constant-syntax">5</span><span class="plain-syntax"> </span><span class="comment-syntax"> for topics of conversation, as used in commands like ASK or CONSULT</span>
|
|
<span class="definition-keyword">define</span> <span class="constant-syntax">CG_IS_PROPERTY_NAME</span><span class="plain-syntax"> </span><span class="constant-syntax">6</span><span class="plain-syntax"> </span><span class="comment-syntax"> for ways to refer to property values used adjectivally</span>
|
|
</pre>
|
|
<p class="commentary firstcommentary"><a id="SP2" class="paragraph-anchor"></a><b>§2. </b>Fixed maxima are generally a bad idea in a compiler (what seems excessive in
|
|
one decade becomes limiting in the next), but in this feature we have to
|
|
make data tables in formats which can be handled by the Inform 6 compiler.
|
|
And that does have two maxima which cannot easily be avoided, so we need to
|
|
respect those here as well.
|
|
</p>
|
|
|
|
<p class="commentary"><span class="extract"><span class="extract-syntax">MAX_ALIASED_COMMANDS</span></span> is harmless enough: it's the maximum number of command
|
|
verbs which can be synonymous with a single other one, as for example if CONSUME
|
|
were synonymous with EAT. Few command verbs need more than four or five, and
|
|
many need none at all.
|
|
</p>
|
|
|
|
<p class="commentary"><span class="extract"><span class="extract-syntax">MAX_LINES_PER_GRAMMAR</span></span> is potentially more biting, since it puts a limit on
|
|
the number of different command syntaxes which any one command verb can have.
|
|
(It applies only to <span class="extract"><span class="extract-syntax">CG_IS_COMMAND</span></span> grammars: the rest are unlimited.) Skilled
|
|
Inform 7 writers can get around this with named tokens, but still, in an ideal
|
|
world we would not impose a limit here.
|
|
</p>
|
|
|
|
<pre class="definitions code-font"><span class="definition-keyword">define</span> <span class="constant-syntax">MAX_ALIASED_COMMANDS</span><span class="plain-syntax"> </span><span class="constant-syntax">32</span>
|
|
<span class="definition-keyword">define</span> <span class="constant-syntax">MAX_LINES_PER_GRAMMAR</span><span class="plain-syntax"> </span><span class="constant-syntax">32</span>
|
|
</pre>
|
|
<p class="commentary firstcommentary"><a id="SP3" class="paragraph-anchor"></a><b>§3. </b>Many of the fields here are relevant only when the CG takes a given <span class="extract"><span class="extract-syntax">cg_is</span></span>
|
|
form, so this is not as bloated a structure as it looks.
|
|
</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">command_grammar</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">cg_is</span><span class="plain-syntax">; </span><span class="comment-syntax"> one of the </span><span class="extract"><span class="extract-syntax">CG_IS_*</span></span><span class="comment-syntax"> values above</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">where_cg_created</span><span class="plain-syntax">; </span><span class="comment-syntax"> for problem message reports</span>
|
|
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">struct</span><span class="plain-syntax"> </span><span class="reserved-syntax">determination_type</span><span class="plain-syntax"> </span><span class="identifier-syntax">cg_type</span><span class="plain-syntax">;</span>
|
|
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">struct</span><span class="plain-syntax"> </span><span class="reserved-syntax">cg_line</span><span class="plain-syntax"> *</span><span class="identifier-syntax">first_line</span><span class="plain-syntax">; </span><span class="comment-syntax"> linked list in creation order</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">struct</span><span class="plain-syntax"> </span><span class="reserved-syntax">cg_line</span><span class="plain-syntax"> *</span><span class="identifier-syntax">sorted_first_line</span><span class="plain-syntax">; </span><span class="comment-syntax"> and in logical applicability order</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">slashed</span><span class="plain-syntax">; </span><span class="comment-syntax"> slashing has been done</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">determined</span><span class="plain-syntax">; </span><span class="comment-syntax"> determination has been done</span>
|
|
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">struct</span><span class="plain-syntax"> </span><span class="identifier-syntax">wording</span><span class="plain-syntax"> </span><span class="identifier-syntax">command</span><span class="plain-syntax">; </span><span class="comment-syntax"> </span><span class="extract"><span class="extract-syntax">CG_IS_COMMAND</span></span><span class="comment-syntax">: what command verb this belongs to</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">struct</span><span class="plain-syntax"> </span><span class="identifier-syntax">wording</span><span class="plain-syntax"> </span><span class="identifier-syntax">aliased_command</span><span class="plain-syntax">[</span><span class="constant-syntax">MAX_ALIASED_COMMANDS</span><span class="plain-syntax">]; </span><span class="comment-syntax"> ...and other commands synonymous</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">no_aliased_commands</span><span class="plain-syntax">; </span><span class="comment-syntax"> ...and how many of them there are</span>
|
|
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">struct</span><span class="plain-syntax"> </span><span class="identifier-syntax">wording</span><span class="plain-syntax"> </span><span class="identifier-syntax">token_name</span><span class="plain-syntax">; </span><span class="comment-syntax"> </span><span class="extract"><span class="extract-syntax">CG_IS_TOKEN</span></span><span class="comment-syntax">: name of this token</span>
|
|
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">struct</span><span class="plain-syntax"> </span><span class="identifier-syntax">inference_subject</span><span class="plain-syntax"> *</span><span class="identifier-syntax">subj_understood</span><span class="plain-syntax">; </span><span class="comment-syntax"> </span><span class="extract"><span class="extract-syntax">CG_IS_SUBJECT</span></span><span class="comment-syntax">: what this provides names for</span>
|
|
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">struct</span><span class="plain-syntax"> </span><span class="identifier-syntax">kind</span><span class="plain-syntax"> *</span><span class="identifier-syntax">kind_understood</span><span class="plain-syntax">; </span><span class="comment-syntax"> </span><span class="extract"><span class="extract-syntax">CG_IS_VALUE</span></span><span class="comment-syntax">: for which type it names an instance of</span>
|
|
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">struct</span><span class="plain-syntax"> </span><span class="identifier-syntax">property</span><span class="plain-syntax"> *</span><span class="identifier-syntax">prn_understood</span><span class="plain-syntax">; </span><span class="comment-syntax"> </span><span class="extract"><span class="extract-syntax">CG_IS_PROPERTY_NAME</span></span><span class="comment-syntax">: which prn this names</span>
|
|
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">struct</span><span class="plain-syntax"> </span><span class="identifier-syntax">cg_compilation_data</span><span class="plain-syntax"> </span><span class="identifier-syntax">compilation_data</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">CLASS_DEFINITION</span>
|
|
<span class="plain-syntax">} </span><span class="reserved-syntax">command_grammar</span><span class="plain-syntax">;</span>
|
|
</pre>
|
|
<ul class="endnotetexts"><li>The structure command_grammar is accessed in 4/ap, 4/act, 4/as, 4/nap, 4/gng, 5/pp, 5/cgl, 5/ts, 6/db, 6/dl, 6/dc and here.</li></ul>
|
|
<p class="commentary firstcommentary"><a id="SP4" class="paragraph-anchor"></a><b>§4. </b>We begin as usual with a constructor and some debug log tracing.
|
|
</p>
|
|
|
|
<pre class="displayed-code all-displayed-code code-font">
|
|
<span class="reserved-syntax">command_grammar</span><span class="plain-syntax"> *</span><span class="function-syntax">CommandGrammars::cg_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">CommandGrammars::cg_new</span></span>:<br/><a href="5-cg.html#SP7">§7</a>, <a href="5-cg.html#SP11">§11</a>, <a href="5-cg.html#SP13">§13</a>, <a href="5-cg.html#SP14">§14</a>, <a href="5-cg.html#SP15">§15</a>, <a href="5-cg.html#SP16">§16</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">cg_is</span><span class="plain-syntax">) {</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">command_grammar</span><span class="plain-syntax"> *</span><span class="identifier-syntax">cg</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">cg</span><span class="plain-syntax"> = </span><span class="identifier-syntax">CREATE</span><span class="plain-syntax">(</span><span class="reserved-syntax">command_grammar</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">command</span><span class="plain-syntax"> = </span><span class="identifier-syntax">EMPTY_WORDING</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">first_line</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">cg</span><span class="plain-syntax">-></span><span class="element-syntax">cg_type</span><span class="plain-syntax"> = </span><a href="5-dt.html#SP2" class="function-link"><span class="function-syntax">DeterminationTypes::new</span></a><span class="plain-syntax">();</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">cg_is</span><span class="plain-syntax"> = </span><span class="identifier-syntax">cg_is</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">token_name</span><span class="plain-syntax"> = </span><span class="identifier-syntax">EMPTY_WORDING</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">no_aliased_commands</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">cg</span><span class="plain-syntax">-></span><span class="element-syntax">sorted_first_line</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">cg</span><span class="plain-syntax">-></span><span class="element-syntax">subj_understood</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">cg</span><span class="plain-syntax">-></span><span class="element-syntax">kind_understood</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">cg</span><span class="plain-syntax">-></span><span class="element-syntax">prn_understood</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">cg</span><span class="plain-syntax">-></span><span class="element-syntax">where_cg_created</span><span class="plain-syntax"> = </span><span class="identifier-syntax">current_sentence</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">slashed</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">cg</span><span class="plain-syntax">-></span><span class="element-syntax">determined</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">cg</span><span class="plain-syntax">-></span><span class="element-syntax">compilation_data</span><span class="plain-syntax"> = </span><span class="identifier-syntax">RTCommandGrammars::new_compilation_data</span><span class="plain-syntax">(</span><span class="identifier-syntax">cg</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">cg</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">CommandGrammars::log</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">CommandGrammars::log</span></span>:<br/>IF Module - <a href="1-im.html#SP2">§2</a>, <a href="1-im.html#SP2_3">§2.3</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">command_grammar</span><span class="plain-syntax"> *</span><span class="identifier-syntax">cg</span><span class="plain-syntax">) {</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">LOG</span><span class="plain-syntax">(</span><span class="string-syntax">"<CG%d:"</span><span class="plain-syntax">, </span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="identifier-syntax">allocation_id</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">cg</span><span class="plain-syntax">-></span><span class="element-syntax">cg_is</span><span class="plain-syntax">) {</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">case</span><span class="plain-syntax"> </span><span class="identifier-syntax">CG_IS_COMMAND:</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">Wordings::empty</span><span class="plain-syntax">(</span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">command</span><span class="plain-syntax">)) </span><span class="identifier-syntax">LOG</span><span class="plain-syntax">(</span><span class="string-syntax">"command=no-verb verb"</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">LOG</span><span class="plain-syntax">(</span><span class="string-syntax">"command=%W"</span><span class="plain-syntax">, </span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">command</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">break</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">case</span><span class="plain-syntax"> </span><span class="identifier-syntax">CG_IS_TOKEN:</span><span class="plain-syntax"> </span><span class="identifier-syntax">LOG</span><span class="plain-syntax">(</span><span class="string-syntax">"token=%W"</span><span class="plain-syntax">, </span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">token_name</span><span class="plain-syntax">); </span><span class="reserved-syntax">break</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">case</span><span class="plain-syntax"> </span><span class="identifier-syntax">CG_IS_SUBJECT:</span><span class="plain-syntax"> </span><span class="identifier-syntax">LOG</span><span class="plain-syntax">(</span><span class="string-syntax">"subject=$j"</span><span class="plain-syntax">, </span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">subj_understood</span><span class="plain-syntax">); </span><span class="reserved-syntax">break</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">case</span><span class="plain-syntax"> </span><span class="identifier-syntax">CG_IS_VALUE:</span><span class="plain-syntax"> </span><span class="identifier-syntax">LOG</span><span class="plain-syntax">(</span><span class="string-syntax">"value=%u"</span><span class="plain-syntax">, </span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">kind_understood</span><span class="plain-syntax">); </span><span class="reserved-syntax">break</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">case</span><span class="plain-syntax"> </span><span class="identifier-syntax">CG_IS_CONSULT:</span><span class="plain-syntax"> </span><span class="identifier-syntax">LOG</span><span class="plain-syntax">(</span><span class="string-syntax">"consult"</span><span class="plain-syntax">); </span><span class="reserved-syntax">break</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">case</span><span class="plain-syntax"> </span><span class="identifier-syntax">CG_IS_PROPERTY_NAME:</span><span class="plain-syntax"> </span><span class="identifier-syntax">LOG</span><span class="plain-syntax">(</span><span class="string-syntax">"property=$Y"</span><span class="plain-syntax">, </span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">prn_understood</span><span class="plain-syntax">); </span><span class="reserved-syntax">break</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">LOG</span><span class="plain-syntax">(</span><span class="string-syntax">"<unknown>"</span><span class="plain-syntax">); </span><span class="reserved-syntax">break</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> }</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">LOG</span><span class="plain-syntax">(</span><span class="string-syntax">">"</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax">}</span>
|
|
</pre>
|
|
<p class="commentary firstcommentary"><a id="SP5" class="paragraph-anchor"></a><b>§5. The CG_IS_COMMAND form. </b>These are the CGs for which CGs were invented, really. Each different
|
|
imperative verb a player can type has a CG of the possible syntaxes the
|
|
player's command can take after that start.
|
|
</p>
|
|
|
|
<p class="commentary">However, such a CG can also handle a number of "aliases", which are verbs
|
|
synonymous to the main one. For instance, the Standard Rules create a CG for
|
|
the command PULL but also give it one alias, DRAG.
|
|
</p>
|
|
|
|
<p class="commentary">Command verbs are of course recognised by their wording, or rather, spelling.
|
|
(We cannot have two different CGs for the verb MARK as understood in two
|
|
different senses, say for marking work and for daubing on a wall.) A special
|
|
case is the empty command verb, the one with no letters at all, which is
|
|
traditionally called the "no verb verb".<sup id="fnref:1"><a href="#fn:1" rel="footnote">1</a></sup> All other verbs are "genuinely
|
|
verbal".
|
|
</p>
|
|
|
|
<ul class="footnotetexts"><li class="footnote" id="fn:1"><p class="inwebfootnote"><sup id="fnref:1"><a href="#fn:1" rel="footnote">1</a></sup> The Standard Rules do not use the no verb verb, but Inform designers
|
|
sometimes do, to allow players to type commands which are meaningful even
|
|
when they do not start with a verb. We treat those as being commands which
|
|
do in fact start with the invisible "no verb verb".
|
|
<a href="#fnref:1" title="return to text"> ↩</a></p></li></ul>
|
|
<pre class="displayed-code all-displayed-code code-font">
|
|
<span class="identifier-syntax">wording</span><span class="plain-syntax"> </span><span class="function-syntax">CommandGrammars::get_verb_text</span><span class="plain-syntax">(</span><span class="reserved-syntax">command_grammar</span><span class="plain-syntax"> *</span><span class="identifier-syntax">cg</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">cg</span><span class="plain-syntax">-></span><span class="element-syntax">command</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">CommandGrammars::cg_is_genuinely_verbal</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">CommandGrammars::cg_is_genuinely_verbal</span></span>:<br/>Command Grammar Lines - <a href="5-cgl.html#SP16">§16</a>, <a href="5-cgl.html#SP16_2">§16.2</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">command_grammar</span><span class="plain-syntax"> *</span><span class="identifier-syntax">cg</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">cg</span><span class="plain-syntax">-></span><span class="element-syntax">cg_is</span><span class="plain-syntax"> == </span><span class="constant-syntax">CG_IS_COMMAND</span><span class="plain-syntax">) && (</span><span class="identifier-syntax">Wordings::nonempty</span><span class="plain-syntax">(</span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">command</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">FALSE</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax">}</span>
|
|
</pre>
|
|
<p class="commentary firstcommentary"><a id="SP6" class="paragraph-anchor"></a><b>§6. </b>Here we find the CG associated with command <span class="extract"><span class="extract-syntax">W</span></span>, or return null if none
|
|
exists (i.e. because no grammar has been created for it). Note that if <span class="extract"><span class="extract-syntax">W</span></span> is
|
|
the <span class="extract"><span class="extract-syntax">EMPTY_WORDING</span></span>, then this function returns the "no verb verb".
|
|
</p>
|
|
|
|
<pre class="displayed-code all-displayed-code code-font">
|
|
<span class="reserved-syntax">command_grammar</span><span class="plain-syntax"> *</span><span class="function-syntax">CommandGrammars::for_command_verb</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">CommandGrammars::for_command_verb</span></span>:<br/><a href="5-cg.html#SP7">§7</a><br/>Understand Sentences - <a href="5-us.html#SP15_1">§15.1</a>, <a href="5-us.html#SP15_2">§15.2</a>, <a href="5-us.html#SP15_3">§15.3</a></span></button><span class="plain-syntax">(</span><span class="identifier-syntax">wording</span><span class="plain-syntax"> </span><span class="identifier-syntax">W</span><span class="plain-syntax">) {</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">command_grammar</span><span class="plain-syntax"> *</span><span class="identifier-syntax">cg</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">LOOP_OVER</span><span class="plain-syntax">(</span><span class="identifier-syntax">cg</span><span class="plain-syntax">, </span><span class="reserved-syntax">command_grammar</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">cg</span><span class="plain-syntax">-></span><span class="element-syntax">cg_is</span><span class="plain-syntax"> == </span><span class="constant-syntax">CG_IS_COMMAND</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">Wordings::empty</span><span class="plain-syntax">(</span><span class="identifier-syntax">W</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">Wordings::empty</span><span class="plain-syntax">(</span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">command</span><span class="plain-syntax">)) </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">cg</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><span class="identifier-syntax">Wordings::match</span><span class="plain-syntax">(</span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">command</span><span class="plain-syntax">, </span><span class="identifier-syntax">W</span><span class="plain-syntax">)) </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">cg</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"><cg-></span><span class="element-syntax">no_aliased_commands</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">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">Wordings::match</span><span class="plain-syntax">(</span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">aliased_command</span><span class="plain-syntax">[</span><span class="identifier-syntax">i</span><span class="plain-syntax">], </span><span class="identifier-syntax">W</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">cg</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">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="SP7" class="paragraph-anchor"></a><b>§7. </b>This does the same, but creating the CG if it does not already exist, so
|
|
that it is guaranteed to return a non-<span class="extract"><span class="extract-syntax">NULL</span></span> pointer:
|
|
</p>
|
|
|
|
<pre class="displayed-code all-displayed-code code-font">
|
|
<span class="reserved-syntax">command_grammar</span><span class="plain-syntax"> *</span><span class="function-syntax">CommandGrammars::for_command_verb_creating</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">CommandGrammars::for_command_verb_creating</span></span>:<br/>Understand Sentences - <a href="5-us.html#SP19_11">§19.11</a></span></button><span class="plain-syntax">(</span><span class="identifier-syntax">wording</span><span class="plain-syntax"> </span><span class="identifier-syntax">W</span><span class="plain-syntax">) {</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">command_grammar</span><span class="plain-syntax"> *</span><span class="identifier-syntax">cg</span><span class="plain-syntax"> = </span><a href="5-cg.html#SP6" class="function-link"><span class="function-syntax">CommandGrammars::for_command_verb</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">W</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">cg</span><span class="plain-syntax">) </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">cg</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">cg</span><span class="plain-syntax"> = </span><a href="5-cg.html#SP4" class="function-link"><span class="function-syntax">CommandGrammars::cg_new</span></a><span class="plain-syntax">(</span><span class="constant-syntax">CG_IS_COMMAND</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">command</span><span class="plain-syntax"> = </span><span class="identifier-syntax">W</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">Wordings::empty</span><span class="plain-syntax">(</span><span class="identifier-syntax">W</span><span class="plain-syntax">)) {</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">LOGIF</span><span class="plain-syntax">(</span><span class="identifier-syntax">GRAMMAR</span><span class="plain-syntax">, </span><span class="string-syntax">"CG%d is the no verb verb\n"</span><span class="plain-syntax">, </span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="identifier-syntax">allocation_id</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">global_compilation_settings</span><span class="plain-syntax">.</span><span class="identifier-syntax">no_verb_verb_exists</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">else</span><span class="plain-syntax"> {</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">LOGIF</span><span class="plain-syntax">(</span><span class="identifier-syntax">GRAMMAR</span><span class="plain-syntax">, </span><span class="string-syntax">"CG%d is the command verb %W\n"</span><span class="plain-syntax">, </span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="identifier-syntax">allocation_id</span><span class="plain-syntax">, </span><span class="identifier-syntax">W</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">cg</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax">}</span>
|
|
</pre>
|
|
<p class="commentary firstcommentary"><a id="SP8" class="paragraph-anchor"></a><b>§8. </b>We now have functions to add or remove command verbs from a given CG as aliases.
|
|
Note that these cannot be called on the no verb verb.
|
|
</p>
|
|
|
|
<pre class="displayed-code all-displayed-code code-font">
|
|
<span class="reserved-syntax">void</span><span class="plain-syntax"> </span><span class="function-syntax">CommandGrammars::add_alias</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">CommandGrammars::add_alias</span></span>:<br/>Understand Sentences - <a href="5-us.html#SP15_3">§15.3</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">command_grammar</span><span class="plain-syntax"> *</span><span class="identifier-syntax">cg</span><span class="plain-syntax">, </span><span class="identifier-syntax">wording</span><span class="plain-syntax"> </span><span class="identifier-syntax">W</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">cg</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">"add alias to null CG"</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">cg</span><span class="plain-syntax">-></span><span class="element-syntax">cg_is</span><span class="plain-syntax"> != </span><span class="constant-syntax">CG_IS_COMMAND</span><span class="plain-syntax">) </span><span class="identifier-syntax">internal_error</span><span class="plain-syntax">(</span><span class="string-syntax">"add alias to non-command CG"</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">cg</span><span class="plain-syntax">-></span><span class="element-syntax">no_aliased_commands</span><span class="plain-syntax"> == </span><span class="constant-syntax">MAX_ALIASED_COMMANDS</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_TooManyAliases</span><span class="plain-syntax">),</span>
|
|
<span class="plain-syntax"> </span><span class="string-syntax">"this 'understand the command ... as ...' makes too many aliases "</span>
|
|
<span class="plain-syntax"> </span><span class="string-syntax">"for the same command"</span><span class="plain-syntax">,</span>
|
|
<span class="plain-syntax"> </span><span class="string-syntax">"exceeding the limit of 32."</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">cg</span><span class="plain-syntax">-></span><span class="element-syntax">aliased_command</span><span class="plain-syntax">[</span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">no_aliased_commands</span><span class="plain-syntax">++] = </span><span class="identifier-syntax">W</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">LOGIF</span><span class="plain-syntax">(</span><span class="identifier-syntax">GRAMMAR</span><span class="plain-syntax">, </span><span class="string-syntax">"Adding alias '%W' to CG%d '%W'\n"</span><span class="plain-syntax">, </span><span class="identifier-syntax">W</span><span class="plain-syntax">,</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="identifier-syntax">allocation_id</span><span class="plain-syntax">, </span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">command</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> }</span>
|
|
<span class="plain-syntax">}</span>
|
|
</pre>
|
|
<p class="commentary firstcommentary"><a id="SP9" class="paragraph-anchor"></a><b>§9. </b>Removing is trickier, since we might be detaching the main command verb, and
|
|
that means that one of the aliases must become the new main verb; or, in the
|
|
worst case, there might be no commands left, and in that case we need to empty
|
|
the CG of grammar lines so that it can either be ignored or re-used.
|
|
</p>
|
|
|
|
<pre class="displayed-code all-displayed-code code-font">
|
|
<span class="reserved-syntax">void</span><span class="plain-syntax"> </span><span class="function-syntax">CommandGrammars::remove_command</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">CommandGrammars::remove_command</span></span>:<br/>Understand Sentences - <a href="5-us.html#SP15_1">§15.1</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">command_grammar</span><span class="plain-syntax"> *</span><span class="identifier-syntax">cg</span><span class="plain-syntax">, </span><span class="identifier-syntax">wording</span><span class="plain-syntax"> </span><span class="identifier-syntax">W</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">cg</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 detach alias command from null CG"</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">cg</span><span class="plain-syntax">-></span><span class="element-syntax">cg_is</span><span class="plain-syntax"> != </span><span class="constant-syntax">CG_IS_COMMAND</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 detach alias command from non-command CG"</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">LOGIF</span><span class="plain-syntax">(</span><span class="identifier-syntax">GRAMMAR</span><span class="plain-syntax">, </span><span class="string-syntax">"Detaching verb '%W' from grammar\n"</span><span class="plain-syntax">, </span><span class="identifier-syntax">W</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">cg</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="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">Wordings::match</span><span class="plain-syntax">(</span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">command</span><span class="plain-syntax">, </span><span class="identifier-syntax">W</span><span class="plain-syntax">)) {</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">LOGIF</span><span class="plain-syntax">(</span><span class="identifier-syntax">GRAMMAR</span><span class="plain-syntax">, </span><span class="string-syntax">"Detached verb is the head-verb\n"</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">cg</span><span class="plain-syntax">-></span><span class="element-syntax">no_aliased_commands</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">cg</span><span class="plain-syntax">-></span><span class="element-syntax">first_line</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">LOGIF</span><span class="plain-syntax">(</span><span class="identifier-syntax">GRAMMAR</span><span class="plain-syntax">, </span><span class="string-syntax">"Which had no aliases: clearing grammar to NULL\n"</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">cg</span><span class="plain-syntax">-></span><span class="element-syntax">command</span><span class="plain-syntax"> = </span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">aliased_command</span><span class="plain-syntax">[--(</span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">no_aliased_commands</span><span class="plain-syntax">)];</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">LOGIF</span><span class="plain-syntax">(</span><span class="identifier-syntax">GRAMMAR</span><span class="plain-syntax">, </span><span class="string-syntax">"Which had aliases: making new head-verb '%W'\n"</span><span class="plain-syntax">,</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">command</span><span class="plain-syntax">);</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">LOGIF</span><span class="plain-syntax">(</span><span class="identifier-syntax">GRAMMAR</span><span class="plain-syntax">, </span><span class="string-syntax">"Detached verb is one of the aliases\n"</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"><cg-></span><span class="element-syntax">no_aliased_commands</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">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">Wordings::match</span><span class="plain-syntax">(</span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">aliased_command</span><span class="plain-syntax">[</span><span class="identifier-syntax">i</span><span class="plain-syntax">], </span><span class="identifier-syntax">W</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">j</span><span class="plain-syntax">=</span><span class="identifier-syntax">i</span><span class="plain-syntax">; </span><span class="identifier-syntax">j</span><span class="function-syntax"><cg-></span><span class="element-syntax">no_aliased_commands</span><span class="plain-syntax">-1; </span><span class="identifier-syntax">j</span><span class="plain-syntax">++)</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">aliased_command</span><span class="plain-syntax">[</span><span class="identifier-syntax">j</span><span class="plain-syntax">] = </span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">aliased_command</span><span class="plain-syntax">[</span><span class="identifier-syntax">j</span><span class="plain-syntax">+1];</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">no_aliased_commands</span><span class="plain-syntax">--;</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">break</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>
|
|
</pre>
|
|
<p class="commentary firstcommentary"><a id="SP10" class="paragraph-anchor"></a><b>§10. </b>This is needed when the designer asks to make actions inaccessible to
|
|
commands from the player, with a line like "Understand nothing as the
|
|
dropping action":
|
|
</p>
|
|
|
|
<pre class="displayed-code all-displayed-code code-font">
|
|
<span class="reserved-syntax">void</span><span class="plain-syntax"> </span><span class="function-syntax">CommandGrammars::remove_action</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">CommandGrammars::remove_action</span></span>:<br/>Actions - <a href="4-act.html#SP7">§7</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">command_grammar</span><span class="plain-syntax"> *</span><span class="identifier-syntax">cg</span><span class="plain-syntax">, </span><span class="reserved-syntax">action_name</span><span class="plain-syntax"> *</span><span class="identifier-syntax">an</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">cg</span><span class="plain-syntax">-></span><span class="element-syntax">cg_is</span><span class="plain-syntax"> == </span><span class="constant-syntax">CG_IS_COMMAND</span><span class="plain-syntax">)</span>
|
|
<span class="plain-syntax"> </span><a href="5-cgl.html#SP6" class="function-link"><span class="function-syntax">CGLines::list_remove</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">cg</span><span class="plain-syntax">, </span><span class="identifier-syntax">an</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax">}</span>
|
|
</pre>
|
|
<p class="commentary firstcommentary"><a id="SP11" class="paragraph-anchor"></a><b>§11. The CG_IS_TOKEN form. </b>These are like text substitutions in reverse. For instance, we could define
|
|
a token "[suitable colour]", which matches any colour name typed by the player.
|
|
</p>
|
|
|
|
<p class="commentary">Tokens are identified solely by their textual names. There is one and only one
|
|
token called "[suitable colour]".
|
|
</p>
|
|
|
|
<pre class="displayed-code all-displayed-code code-font">
|
|
<span class="reserved-syntax">command_grammar</span><span class="plain-syntax"> *</span><span class="function-syntax">CommandGrammars::new_named_token</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">CommandGrammars::new_named_token</span></span>:<br/><a href="5-cg.html#SP12">§12</a><br/>Understand Sentences - <a href="5-us.html#SP19_11">§19.11</a></span></button><span class="plain-syntax">(</span><span class="identifier-syntax">wording</span><span class="plain-syntax"> </span><span class="identifier-syntax">W</span><span class="plain-syntax">) {</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">command_grammar</span><span class="plain-syntax"> *</span><span class="identifier-syntax">cg</span><span class="plain-syntax"> = </span><a href="5-cg.html#SP11" class="function-link"><span class="function-syntax">CommandGrammars::named_token_by_name</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">W</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">cg</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">cg</span><span class="plain-syntax"> = </span><a href="5-cg.html#SP4" class="function-link"><span class="function-syntax">CommandGrammars::cg_new</span></a><span class="plain-syntax">(</span><span class="constant-syntax">CG_IS_TOKEN</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">token_name</span><span class="plain-syntax"> = </span><span class="identifier-syntax">W</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">cg</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax">}</span>
|
|
|
|
<span class="reserved-syntax">command_grammar</span><span class="plain-syntax"> *</span><span class="function-syntax">CommandGrammars::named_token_by_name</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">CommandGrammars::named_token_by_name</span></span>:<br/><a href="5-cg.html#SP12">§12</a><br/>Command Grammar Tokens - <a href="5-cgt.html#SP12">§12</a></span></button><span class="plain-syntax">(</span><span class="identifier-syntax">wording</span><span class="plain-syntax"> </span><span class="identifier-syntax">W</span><span class="plain-syntax">) {</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">command_grammar</span><span class="plain-syntax"> *</span><span class="identifier-syntax">cg</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">LOOP_OVER</span><span class="plain-syntax">(</span><span class="identifier-syntax">cg</span><span class="plain-syntax">, </span><span class="reserved-syntax">command_grammar</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">cg</span><span class="plain-syntax">-></span><span class="element-syntax">cg_is</span><span class="plain-syntax"> == </span><span class="constant-syntax">CG_IS_TOKEN</span><span class="plain-syntax">) && (</span><span class="identifier-syntax">Wordings::match</span><span class="plain-syntax">(</span><span class="identifier-syntax">W</span><span class="plain-syntax">, </span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">token_name</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">cg</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="SP12" class="paragraph-anchor"></a><b>§12. </b>A slight variation is provided by those which are defined by Inter functions.
|
|
</p>
|
|
|
|
<pre class="displayed-code all-displayed-code code-font">
|
|
<span class="reserved-syntax">void</span><span class="plain-syntax"> </span><span class="function-syntax">CommandGrammars::new_translated_token</span><span class="plain-syntax">(</span><span class="identifier-syntax">wording</span><span class="plain-syntax"> </span><span class="identifier-syntax">W</span><span class="plain-syntax">, </span><span class="identifier-syntax">parse_node</span><span class="plain-syntax"> *</span><span class="identifier-syntax">id</span><span class="plain-syntax">) {</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">command_grammar</span><span class="plain-syntax"> *</span><span class="identifier-syntax">cg</span><span class="plain-syntax"> = </span><a href="5-cg.html#SP11" class="function-link"><span class="function-syntax">CommandGrammars::named_token_by_name</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">W</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">cg</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="plain-syntax"> </span><span class="identifier-syntax">_p_</span><span class="plain-syntax">(</span><span class="identifier-syntax">PM_GrammarTranslatedAlready</span><span class="plain-syntax">),</span>
|
|
<span class="plain-syntax"> </span><span class="string-syntax">"this grammar token has already been translated"</span><span class="plain-syntax">,</span>
|
|
<span class="plain-syntax"> </span><span class="string-syntax">"so there must be some duplication somewhere."</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> }</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">cg</span><span class="plain-syntax"> = </span><a href="5-cg.html#SP11" class="function-link"><span class="function-syntax">CommandGrammars::new_named_token</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">W</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">RTCommandGrammars::set_CG_IS_TOKEN_identifier</span><span class="plain-syntax">(</span><span class="identifier-syntax">cg</span><span class="plain-syntax">, </span><span class="identifier-syntax">Node::get_text</span><span class="plain-syntax">(</span><span class="identifier-syntax">id</span><span class="plain-syntax">));</span>
|
|
<span class="plain-syntax">}</span>
|
|
</pre>
|
|
<p class="commentary firstcommentary"><a id="SP13" class="paragraph-anchor"></a><b>§13. The CG_IS_SUBJECT form. </b>Any inference subject can in theory be given a CG, used to parse unusual forms
|
|
of its name. If the source reads:
|
|
</p>
|
|
|
|
<blockquote>
|
|
<p>Understand "frog" as the Brazilian leaping toad.</p>
|
|
</blockquote>
|
|
|
|
<p class="commentary">then "frog" is added to the CG for the toad's inference subject.
|
|
</p>
|
|
|
|
<p class="commentary">The toad is of course an object, and in fact although there are many other
|
|
inference subjects in Inform, this system is used only for objects and their
|
|
kinds.<sup id="fnref:2"><a href="#fn:2" rel="footnote">2</a></sup>
|
|
</p>
|
|
|
|
<ul class="footnotetexts"><li class="footnote" id="fn:2"><p class="inwebfootnote"><sup id="fnref:2"><a href="#fn:2" rel="footnote">2</a></sup> Because in our run-time representation, objects and kinds of objects have
|
|
data which makes it convenient for them to provide their own "general parsing
|
|
routines", whereas enumeration values do not. So to give exotic names to instances
|
|
of non-object kinds we use <span class="extract"><span class="extract-syntax">CG_IS_VALUE</span></span> instead. And in any case numbers or
|
|
times of day are not inference subjects anyway, so we would need <span class="extract"><span class="extract-syntax">CG_IS_VALUE</span></span>
|
|
in any case for those.
|
|
<a href="#fnref:2" title="return to text"> ↩</a></p></li></ul>
|
|
<pre class="displayed-code all-displayed-code code-font">
|
|
<span class="reserved-syntax">command_grammar</span><span class="plain-syntax"> *</span><span class="function-syntax">CommandGrammars::for_subject</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">CommandGrammars::for_subject</span></span>:<br/>Understand Sentences - <a href="5-us.html#SP19_11">§19.11</a></span></button><span class="plain-syntax">(</span><span class="identifier-syntax">inference_subject</span><span class="plain-syntax"> *</span><span class="identifier-syntax">subj</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">PARSING_DATA_FOR_SUBJ</span><span class="plain-syntax">(</span><span class="identifier-syntax">subj</span><span class="plain-syntax">)-></span><span class="element-syntax">understand_as_this_subject</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">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">PARSING_DATA_FOR_SUBJ</span><span class="plain-syntax">(</span><span class="identifier-syntax">subj</span><span class="plain-syntax">)-></span><span class="element-syntax">understand_as_this_subject</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">command_grammar</span><span class="plain-syntax"> *</span><span class="identifier-syntax">cg</span><span class="plain-syntax"> = </span><a href="5-cg.html#SP4" class="function-link"><span class="function-syntax">CommandGrammars::cg_new</span></a><span class="plain-syntax">(</span><span class="constant-syntax">CG_IS_SUBJECT</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">PARSING_DATA_FOR_SUBJ</span><span class="plain-syntax">(</span><span class="identifier-syntax">subj</span><span class="plain-syntax">)-></span><span class="identifier-syntax">understand_as_this_subject</span><span class="plain-syntax"> = </span><span class="identifier-syntax">cg</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">subj_understood</span><span class="plain-syntax"> = </span><span class="identifier-syntax">subj</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">cg</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax">}</span>
|
|
</pre>
|
|
<p class="commentary firstcommentary"><a id="SP14" class="paragraph-anchor"></a><b>§14. The CG_IS_VALUE form. </b>This is used to store names for, say, particular numbers, or enumeration
|
|
values. The following examples both involve <span class="extract"><span class="extract-syntax">CG_IS_VALUE</span></span> grammars:
|
|
</p>
|
|
|
|
<pre class="displayed-code all-displayed-code code-font">
|
|
<span class="identifier-syntax">Understand</span><span class="plain-syntax"> </span><span class="string-syntax">"deuce"</span><span class="plain-syntax"> </span><span class="identifier-syntax">as</span><span class="plain-syntax"> </span><span class="constant-syntax">2</span><span class="plain-syntax">.</span>
|
|
<span class="identifier-syntax">Colour</span><span class="plain-syntax"> </span><span class="identifier-syntax">is</span><span class="plain-syntax"> </span><span class="identifier-syntax">a</span><span class="plain-syntax"> </span><span class="identifier-syntax">kind</span><span class="plain-syntax"> </span><span class="identifier-syntax">of</span><span class="plain-syntax"> </span><span class="identifier-syntax">value</span><span class="plain-syntax">. </span><span class="identifier-syntax">Red</span><span class="plain-syntax">, </span><span class="identifier-syntax">blue</span><span class="plain-syntax"> </span><span class="identifier-syntax">and</span><span class="plain-syntax"> </span><span class="identifier-syntax">green</span><span class="plain-syntax"> </span><span class="identifier-syntax">are</span><span class="plain-syntax"> </span><span class="identifier-syntax">colours</span><span class="plain-syntax">.</span>
|
|
<span class="identifier-syntax">Understand</span><span class="plain-syntax"> </span><span class="string-syntax">"scarlet"</span><span class="plain-syntax"> </span><span class="identifier-syntax">as</span><span class="plain-syntax"> </span><span class="identifier-syntax">red</span><span class="plain-syntax">.</span>
|
|
</pre>
|
|
<p class="commentary">Note however that a <span class="extract"><span class="extract-syntax">CG_IS_VALUE</span></span> grammar is associated with a kind: unlike
|
|
the case of <span class="extract"><span class="extract-syntax">CG_IS_SUBJECT</span></span>, there isn't a different one for each individual
|
|
value. There is just one grammar holding all possible fancy names for
|
|
different numbers, for example; the <span class="extract"><span class="extract-syntax">CG_IS_VALUE</span></span> grammar for <span class="extract"><span class="extract-syntax">K_number</span></span>.
|
|
</p>
|
|
|
|
<pre class="displayed-code all-displayed-code code-font">
|
|
<span class="reserved-syntax">command_grammar</span><span class="plain-syntax"> *</span><span class="function-syntax">CommandGrammars::for_kind</span><button class="popup" onclick="togglePopup('usagePopup12')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup12">Usage of <span class="code-font"><span class="function-syntax">CommandGrammars::for_kind</span></span>:<br/>Understand Sentences - <a href="5-us.html#SP19_11">§19.11</a></span></button><span class="plain-syntax">(</span><span class="identifier-syntax">kind</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">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">K</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">"cannot get CG for null kind"</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><a href="5-cg.html#SP14" class="function-link"><span class="function-syntax">CommandGrammars::get_parsing_grammar</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">K</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">return</span><span class="plain-syntax"> </span><a href="5-cg.html#SP14" class="function-link"><span class="function-syntax">CommandGrammars::get_parsing_grammar</span></a><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">command_grammar</span><span class="plain-syntax"> *</span><span class="identifier-syntax">cg</span><span class="plain-syntax"> = </span><a href="5-cg.html#SP4" class="function-link"><span class="function-syntax">CommandGrammars::cg_new</span></a><span class="plain-syntax">(</span><span class="constant-syntax">CG_IS_VALUE</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">Kinds::Behaviour::is_object</span><span class="plain-syntax">(</span><span class="identifier-syntax">K</span><span class="plain-syntax">)) </span><span class="identifier-syntax">internal_error</span><span class="plain-syntax">(</span><span class="string-syntax">"cannot set CG for K_object"</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">Kinds::Behaviour::is_subkind_of_object</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">internal_error</span><span class="plain-syntax">(</span><span class="string-syntax">"object kinds should not have a CG_IS_VALUE grammar"</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">K</span><span class="plain-syntax">-></span><span class="identifier-syntax">construct</span><span class="plain-syntax">-></span><span class="identifier-syntax">understand_as_values</span><span class="plain-syntax"> = </span><span class="identifier-syntax">cg</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">kind_understood</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">cg</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax">}</span>
|
|
|
|
<span class="reserved-syntax">command_grammar</span><span class="plain-syntax"> *</span><span class="function-syntax">CommandGrammars::get_parsing_grammar</span><span class="plain-syntax">(</span><span class="identifier-syntax">kind</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">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">K</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">Kinds::Behaviour::is_object</span><span class="plain-syntax">(</span><span class="identifier-syntax">K</span><span class="plain-syntax">)) </span><span class="identifier-syntax">internal_error</span><span class="plain-syntax">(</span><span class="string-syntax">"cannot get CG for K_object"</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">K</span><span class="plain-syntax">-></span><span class="identifier-syntax">construct</span><span class="plain-syntax">-></span><span class="identifier-syntax">understand_as_values</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax">}</span>
|
|
</pre>
|
|
<p class="commentary firstcommentary"><a id="SP15" class="paragraph-anchor"></a><b>§15. The CG_IS_CONSULT form. </b>Consultation grammars<sup id="fnref:3"><a href="#fn:3" rel="footnote">3</a></sup> are used to handle topics of conversation and other
|
|
free-form textual parts of commands typed by the player: the player can legally
|
|
type ASK JETHRO ABOUT ... and put almost anything after ABOUT, and we need ways
|
|
to parse that material.
|
|
</p>
|
|
|
|
<p class="commentary">The model here is rather different. Because the topic being discussed could be
|
|
almost anything — maybe Jethro knows about WHEAT PRICES, the HARVEST and
|
|
QUANTUM CHROMODYNAMICS (he has hidden depths) — there is no obvious data
|
|
structure in Inform to attach such a grammar to. Instead, code wishing to
|
|
create a new consultation should first call <a href="5-cg.html#SP15" class="internal">CommandGrammars::prepare_consultation_cg</a>,
|
|
then access the current one being made using <a href="5-cg.html#SP15" class="internal">CommandGrammars::get_consultation_cg</a>.
|
|
Note that exactly one consultation can be made at a time.
|
|
</p>
|
|
|
|
<ul class="footnotetexts"><li class="footnote" id="fn:3"><p class="inwebfootnote"><sup id="fnref:3"><a href="#fn:3" rel="footnote">3</a></sup> The term "consultation" goes back to the origins of this feature in the
|
|
CONSULT command, which in turn goes right back to a game called "Curses" (1993),
|
|
in which players consulted a biographical dictionary of the Meldrew family.
|
|
<a href="#fnref:3" title="return to text"> ↩</a></p></li></ul>
|
|
<pre class="displayed-code all-displayed-code code-font">
|
|
<span class="reserved-syntax">command_grammar</span><span class="plain-syntax"> *</span><span class="identifier-syntax">consultation_gv</span><span class="plain-syntax"> = </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">;</span>
|
|
|
|
<span class="reserved-syntax">void</span><span class="plain-syntax"> </span><span class="function-syntax">CommandGrammars::prepare_consultation_cg</span><button class="popup" onclick="togglePopup('usagePopup13')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup13">Usage of <span class="code-font"><span class="function-syntax">CommandGrammars::prepare_consultation_cg</span></span>:<br/>Understand Sentences - <a href="5-us.html#SP18">§18</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">void</span><span class="plain-syntax">) {</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">consultation_gv</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">command_grammar</span><span class="plain-syntax"> *</span><span class="function-syntax">CommandGrammars::get_consultation_cg</span><button class="popup" onclick="togglePopup('usagePopup14')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup14">Usage of <span class="code-font"><span class="function-syntax">CommandGrammars::get_consultation_cg</span></span>:<br/>Understand Sentences - <a href="5-us.html#SP18">§18</a>, <a href="5-us.html#SP19_11">§19.11</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">void</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">consultation_gv</span><span class="plain-syntax"> == </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">) </span><span class="identifier-syntax">consultation_gv</span><span class="plain-syntax"> = </span><a href="5-cg.html#SP4" class="function-link"><span class="function-syntax">CommandGrammars::cg_new</span></a><span class="plain-syntax">(</span><span class="constant-syntax">CG_IS_CONSULT</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">consultation_gv</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax">}</span>
|
|
</pre>
|
|
<p class="commentary firstcommentary"><a id="SP16" class="paragraph-anchor"></a><b>§16. The CG_IS_PROPERTY_NAME form. </b>A few properties can be recognised by adjectives in the player's commands.
|
|
For example, we might allow OPEN or CLOSED in connection with doors. If so,
|
|
we may want to allow synonyms or other ways to express this, and so a
|
|
property value used adjectivally like this can be given a CG.
|
|
</p>
|
|
|
|
<pre class="displayed-code all-displayed-code code-font">
|
|
<span class="reserved-syntax">command_grammar</span><span class="plain-syntax"> *</span><span class="function-syntax">CommandGrammars::for_prn</span><button class="popup" onclick="togglePopup('usagePopup15')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup15">Usage of <span class="code-font"><span class="function-syntax">CommandGrammars::for_prn</span></span>:<br/>Understand Sentences - <a href="5-us.html#SP19_11">§19.11</a></span></button><span class="plain-syntax">(</span><span class="identifier-syntax">property</span><span class="plain-syntax"> *</span><span class="identifier-syntax">prn</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">EitherOrProperties::get_parsing_grammar</span><span class="plain-syntax">(</span><span class="identifier-syntax">prn</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">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">EitherOrProperties::get_parsing_grammar</span><span class="plain-syntax">(</span><span class="identifier-syntax">prn</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">command_grammar</span><span class="plain-syntax"> *</span><span class="identifier-syntax">cg</span><span class="plain-syntax"> = </span><a href="5-cg.html#SP4" class="function-link"><span class="function-syntax">CommandGrammars::cg_new</span></a><span class="plain-syntax">(</span><span class="constant-syntax">CG_IS_PROPERTY_NAME</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">EitherOrProperties::set_parsing_grammar</span><span class="plain-syntax">(</span><span class="identifier-syntax">prn</span><span class="plain-syntax">, </span><span class="identifier-syntax">cg</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">prn_understood</span><span class="plain-syntax"> = </span><span class="identifier-syntax">prn</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">cg</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax">}</span>
|
|
</pre>
|
|
<p class="commentary firstcommentary"><a id="SP17" class="paragraph-anchor"></a><b>§17. The list of grammar lines. </b>Every CG has a list of CGLs: indeed, this list is the point of the grammar. Here
|
|
we test this for emptiness, and provide for adding to it. In general removals
|
|
are not possible, but see <a href="5-cg.html#SP10" class="internal">CommandGrammars::remove_action</a> above.
|
|
</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">CommandGrammars::is_empty</span><button class="popup" onclick="togglePopup('usagePopup16')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup16">Usage of <span class="code-font"><span class="function-syntax">CommandGrammars::is_empty</span></span>:<br/>Understand Sentences - <a href="5-us.html#SP15_2">§15.2</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">command_grammar</span><span class="plain-syntax"> *</span><span class="identifier-syntax">cg</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">cg</span><span class="plain-syntax"> == </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">) || (</span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">first_line</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">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">FALSE</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">CommandGrammars::add_line</span><button class="popup" onclick="togglePopup('usagePopup17')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup17">Usage of <span class="code-font"><span class="function-syntax">CommandGrammars::add_line</span></span>:<br/>Understand Sentences - <a href="5-us.html#SP19">§19</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">command_grammar</span><span class="plain-syntax"> *</span><span class="identifier-syntax">cg</span><span class="plain-syntax">, </span><span class="reserved-syntax">cg_line</span><span class="plain-syntax"> *</span><span class="identifier-syntax">cgl</span><span class="plain-syntax">) {</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">LOGIF</span><span class="plain-syntax">(</span><span class="identifier-syntax">GRAMMAR</span><span class="plain-syntax">, </span><span class="string-syntax">"$G + line: $g\n"</span><span class="plain-syntax">, </span><span class="identifier-syntax">cg</span><span class="plain-syntax">, </span><span class="identifier-syntax">cgl</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">cg</span><span class="plain-syntax">-></span><span class="element-syntax">cg_is</span><span class="plain-syntax"> == </span><span class="constant-syntax">CG_IS_COMMAND</span><span class="plain-syntax">) &&</span>
|
|
<span class="plain-syntax"> (</span><a href="5-cgl.html#SP4" class="function-link"><span class="function-syntax">CGLines::list_length</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">cg</span><span class="plain-syntax">) >= </span><span class="constant-syntax">MAX_LINES_PER_GRAMMAR</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_TooManyGrammarLines</span><span class="plain-syntax">),</span>
|
|
<span class="plain-syntax"> </span><span class="string-syntax">"this command verb now has too many Understand possibilities"</span><span class="plain-syntax">,</span>
|
|
<span class="plain-syntax"> </span><span class="string-syntax">"that is, there are too many 'Understand \"whatever ...\" as ...' "</span>
|
|
<span class="plain-syntax"> </span><span class="string-syntax">"which share the same initial word 'whatever'. The best way to "</span>
|
|
<span class="plain-syntax"> </span><span class="string-syntax">"get around this is to try to consolidate some of those lines "</span>
|
|
<span class="plain-syntax"> </span><span class="string-syntax">"together, perhaps by using slashes to combine alternative "</span>
|
|
<span class="plain-syntax"> </span><span class="string-syntax">"wordings, or by defining new grammar tokens [in square brackets]."</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><a href="5-cgl.html#SP5" class="function-link"><span class="function-syntax">CGLines::list_add</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">cg</span><span class="plain-syntax">, </span><span class="identifier-syntax">cgl</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> }</span>
|
|
<span class="plain-syntax">}</span>
|
|
</pre>
|
|
<p class="commentary firstcommentary"><a id="SP18" class="paragraph-anchor"></a><b>§18. </b>As noted above, some CGs are used to refer to objects or values: others not.
|
|
This returns the kind if so, or <span class="extract"><span class="extract-syntax">NULL</span></span> if not.
|
|
</p>
|
|
|
|
<pre class="displayed-code all-displayed-code code-font">
|
|
<span class="identifier-syntax">kind</span><span class="plain-syntax"> *</span><span class="function-syntax">CommandGrammars::get_kind_matched</span><button class="popup" onclick="togglePopup('usagePopup18')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup18">Usage of <span class="code-font"><span class="function-syntax">CommandGrammars::get_kind_matched</span></span>:<br/>Command Grammar Tokens - <a href="5-cgt.html#SP16">§16</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">command_grammar</span><span class="plain-syntax"> *</span><span class="identifier-syntax">cg</span><span class="plain-syntax">) {</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><a href="5-dt.html#SP4" class="function-link"><span class="function-syntax">DeterminationTypes::get_single_kind</span></a><span class="plain-syntax">(&(</span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">cg_type</span><span class="plain-syntax">));</span>
|
|
<span class="plain-syntax">}</span>
|
|
</pre>
|
|
<p class="commentary firstcommentary"><a id="SP19" class="paragraph-anchor"></a><b>§19. Slashing and determining. </b>CGs are created and then gradually accumulate grammar lines in response to the
|
|
stream of "Understand... as..." sentences. Once all of that is done, we have to
|
|
make sense of it all, which we do in two phases: "slashing" and "determining".
|
|
</p>
|
|
|
|
<p class="commentary">Slashing is really a grammar-line based activity, so we do no more than pass
|
|
the buck down to <a href="5-cgl.html" class="internal">Command Grammar Lines</a>.
|
|
</p>
|
|
|
|
<pre class="displayed-code all-displayed-code code-font">
|
|
<span class="reserved-syntax">void</span><span class="plain-syntax"> </span><span class="function-syntax">CommandGrammars::prepare</span><button class="popup" onclick="togglePopup('usagePopup19')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup19">Usage of <span class="code-font"><span class="function-syntax">CommandGrammars::prepare</span></span>:<br/>Parsing Plugin - <a href="5-pp.html#SP2">§2</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">void</span><span class="plain-syntax">) {</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">command_grammar</span><span class="plain-syntax"> *</span><span class="identifier-syntax">cg</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">Log::new_stage</span><span class="plain-syntax">(</span><span class="identifier-syntax">I</span><span class="string-syntax">"Slashing command grammar"</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">LOOP_OVER</span><span class="plain-syntax">(</span><span class="identifier-syntax">cg</span><span class="plain-syntax">, </span><span class="reserved-syntax">command_grammar</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">cg</span><span class="plain-syntax">-></span><span class="element-syntax">slashed</span><span class="plain-syntax"> == </span><span class="identifier-syntax">FALSE</span><span class="plain-syntax">) && (</span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">first_line</span><span class="plain-syntax">)) {</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">LOGIF</span><span class="plain-syntax">(</span><span class="identifier-syntax">GRAMMAR_CONSTRUCTION</span><span class="plain-syntax">, </span><span class="string-syntax">"Slashing $G\n"</span><span class="plain-syntax">, </span><span class="identifier-syntax">cg</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><a href="5-cgl.html#SP15" class="function-link"><span class="function-syntax">CGLines::slash</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">cg</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">slashed</span><span class="plain-syntax"> = </span><span class="identifier-syntax">TRUE</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> }</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">Log::new_stage</span><span class="plain-syntax">(</span><span class="identifier-syntax">I</span><span class="string-syntax">"Determining command grammar"</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">LOOP_OVER</span><span class="plain-syntax">(</span><span class="identifier-syntax">cg</span><span class="plain-syntax">, </span><span class="reserved-syntax">command_grammar</span><span class="plain-syntax">)</span>
|
|
<span class="plain-syntax"> </span><a href="5-cg.html#SP20" class="function-link"><span class="function-syntax">CommandGrammars::determine</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">cg</span><span class="plain-syntax">, </span><span class="constant-syntax">0</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax">}</span>
|
|
</pre>
|
|
<p class="commentary firstcommentary"><a id="SP20" class="paragraph-anchor"></a><b>§20. </b>Determining is more involved, and is also recursive. What we are doing is
|
|
trying to work values a CG can produce, in terms of what value it refers to —
|
|
if any. For <span class="extract"><span class="extract-syntax">CG_IS_COMMAND</span></span> grammars, for example, it will be <span class="extract"><span class="extract-syntax">NULL</span></span>, but
|
|
for <span class="extract"><span class="extract-syntax">CG_IS_VALUE</span></span>, it might for example be a description meaning "any value
|
|
with kind <span class="extract"><span class="extract-syntax">K_number</span></span>.
|
|
</p>
|
|
|
|
<p class="commentary">Determination is hierarchical. To determine a CG we determine each of its
|
|
lines, and they in turn determine each of their tokens. But some of those tokens
|
|
will themselves be defined by <span class="extract"><span class="extract-syntax">CG_IS_TOKEN</span></span> grammars, and determining those
|
|
recurses back here.
|
|
</p>
|
|
|
|
<pre class="displayed-code all-displayed-code code-font">
|
|
<span class="identifier-syntax">parse_node</span><span class="plain-syntax"> *</span><span class="function-syntax">CommandGrammars::determine</span><button class="popup" onclick="togglePopup('usagePopup20')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup20">Usage of <span class="code-font"><span class="function-syntax">CommandGrammars::determine</span></span>:<br/><a href="5-cg.html#SP19">§19</a><br/>Command Grammar Tokens - <a href="5-cgt.html#SP14">§14</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">command_grammar</span><span class="plain-syntax"> *</span><span class="identifier-syntax">cg</span><span class="plain-syntax">, </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">depth</span><span class="plain-syntax">) {</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">current_sentence</span><span class="plain-syntax"> = </span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">where_cg_created</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="named-paragraph-container code-font"><a href="5-cg.html#SP20_1" class="named-paragraph-link"><span class="named-paragraph">If this CG produces a value we have determined already, return that</span><span class="named-paragraph-number">20.1</span></a></span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="named-paragraph-container code-font"><a href="5-cg.html#SP20_2" class="named-paragraph-link"><span class="named-paragraph">If recursion went impossibly deep, the CG grammar must be ill-founded</span><span class="named-paragraph-number">20.2</span></a></span><span class="plain-syntax">;</span>
|
|
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">LOGIF</span><span class="plain-syntax">(</span><span class="identifier-syntax">GRAMMAR_CONSTRUCTION</span><span class="plain-syntax">, </span><span class="string-syntax">"Determining $G\n"</span><span class="plain-syntax">, </span><span class="identifier-syntax">cg</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">LOG_INDENT</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">LOOP_THROUGH_UNSORTED_CG_LINES</span><span class="plain-syntax">(</span><span class="identifier-syntax">cgl</span><span class="plain-syntax">, </span><span class="identifier-syntax">cg</span><span class="plain-syntax">)</span>
|
|
<span class="plain-syntax"> </span><a href="5-cgl.html#SP16" class="function-link"><span class="function-syntax">CGLines::cgl_determine</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">cgl</span><span class="plain-syntax">, </span><span class="identifier-syntax">cg</span><span class="plain-syntax">, </span><span class="identifier-syntax">depth</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">LOG_OUTDENT</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="identifier-syntax">spec_union</span><span class="plain-syntax"> = </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="named-paragraph-container code-font"><a href="5-cg.html#SP20_3" class="named-paragraph-link"><span class="named-paragraph">Take the union of the single-term results of each line</span><span class="named-paragraph-number">20.3</span></a></span><span class="plain-syntax">;</span>
|
|
|
|
<span class="plain-syntax"> </span><span class="named-paragraph-container code-font"><a href="5-cg.html#SP20_4" class="named-paragraph-link"><span class="named-paragraph">Cache the answer so that we need not determine it again</span><span class="named-paragraph-number">20.4</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">spec_union</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax">}</span>
|
|
</pre>
|
|
<p class="commentary firstcommentary"><a id="SP20_1" class="paragraph-anchor"></a><b>§20.1. </b><span class="named-paragraph-container code-font"><span class="named-paragraph-defn">If this CG produces a value we have determined already, return that</span><span class="named-paragraph-number">20.1</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">cg</span><span class="plain-syntax">-></span><span class="element-syntax">determined</span><span class="plain-syntax">) </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><a href="5-dt.html#SP4" class="function-link"><span class="function-syntax">DeterminationTypes::get_single_term</span></a><span class="plain-syntax">(&(</span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">cg_type</span><span class="plain-syntax">));</span>
|
|
</pre>
|
|
<ul class="endnotetexts"><li>This code is used in <a href="5-cg.html#SP20">§20</a>.</li></ul>
|
|
<p class="commentary firstcommentary"><a id="SP20_2" class="paragraph-anchor"></a><b>§20.2. </b><span class="named-paragraph-container code-font"><span class="named-paragraph-defn">If recursion went impossibly deep, the CG grammar must be ill-founded</span><span class="named-paragraph-number">20.2</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">depth</span><span class="plain-syntax"> > </span><span class="identifier-syntax">NUMBER_CREATED</span><span class="plain-syntax">(</span><span class="reserved-syntax">command_grammar</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_GrammarIllFounded</span><span class="plain-syntax">),</span>
|
|
<span class="plain-syntax"> </span><span class="string-syntax">"grammar tokens are not allowed to be defined in terms of themselves"</span><span class="plain-syntax">,</span>
|
|
<span class="plain-syntax"> </span><span class="string-syntax">"either directly or indirectly."</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>
|
|
<ul class="endnotetexts"><li>This code is used in <a href="5-cg.html#SP20">§20</a>.</li></ul>
|
|
<p class="commentary firstcommentary"><a id="SP20_3" class="paragraph-anchor"></a><b>§20.3. </b>The "union" referred to below is the widest possible description which
|
|
matches the single term of the determination type of each CGL in the list.
|
|
</p>
|
|
|
|
<p class="commentary"><span class="named-paragraph-container code-font"><span class="named-paragraph-defn">Take the union of the single-term results of each line</span><span class="named-paragraph-number">20.3</span></span><span class="comment-syntax"> =</span>
|
|
</p>
|
|
|
|
<pre class="displayed-code all-displayed-code code-font">
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">LOGIF</span><span class="plain-syntax">(</span><span class="identifier-syntax">GRAMMAR_CONSTRUCTION</span><span class="plain-syntax">, </span><span class="string-syntax">"Taking union on $G\n"</span><span class="plain-syntax">, </span><span class="identifier-syntax">cg</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">LOG_INDENT</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_flag</span><span class="plain-syntax"> = </span><span class="identifier-syntax">TRUE</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">LOOP_THROUGH_UNSORTED_CG_LINES</span><span class="plain-syntax">(</span><span class="identifier-syntax">cgl</span><span class="plain-syntax">, </span><span class="identifier-syntax">cg</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="identifier-syntax">spec_of_line</span><span class="plain-syntax"> = </span><a href="5-dt.html#SP4" class="function-link"><span class="function-syntax">DeterminationTypes::get_single_term</span></a><span class="plain-syntax">(&(</span><span class="identifier-syntax">cgl</span><span class="plain-syntax">-></span><span class="element-syntax">cgl_type</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">first_flag</span><span class="plain-syntax">) { </span><span class="comment-syntax"> initially no expectations: </span><span class="extract"><span class="extract-syntax">spec_union</span></span><span class="comment-syntax"> is meaningless</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">spec_union</span><span class="plain-syntax"> = </span><span class="identifier-syntax">spec_of_line</span><span class="plain-syntax">; </span><span class="comment-syntax"> so we set it to the first result</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">first_flag</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">else</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_union</span><span class="plain-syntax"> == </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">) && (</span><span class="identifier-syntax">spec_of_line</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">continue</span><span class="plain-syntax">; </span><span class="comment-syntax"> we expected to find no result, and did: so no problem</span>
|
|
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> ((</span><span class="identifier-syntax">spec_union</span><span class="plain-syntax">) && (</span><span class="identifier-syntax">spec_of_line</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">Dash::compatible_with_description</span><span class="plain-syntax">(</span><span class="identifier-syntax">spec_union</span><span class="plain-syntax">, </span><span class="identifier-syntax">spec_of_line</span><span class="plain-syntax">) == </span><span class="identifier-syntax">ALWAYS_MATCH</span><span class="plain-syntax">) {</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">spec_union</span><span class="plain-syntax"> = </span><span class="identifier-syntax">spec_of_line</span><span class="plain-syntax">; </span><span class="comment-syntax"> here </span><span class="extract"><span class="extract-syntax">spec_of_line</span></span><span class="comment-syntax"> was a wider type</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">continue</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">Dash::compatible_with_description</span><span class="plain-syntax">(</span><span class="identifier-syntax">spec_of_line</span><span class="plain-syntax">, </span><span class="identifier-syntax">spec_union</span><span class="plain-syntax">) == </span><span class="identifier-syntax">ALWAYS_MATCH</span><span class="plain-syntax">) {</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">continue</span><span class="plain-syntax">; </span><span class="comment-syntax"> here </span><span class="extract"><span class="extract-syntax">spec_union</span></span><span class="comment-syntax"> was already wide enough</span>
|
|
<span class="plain-syntax"> }</span>
|
|
<span class="plain-syntax"> }</span>
|
|
<span class="plain-syntax"> </span><span class="named-paragraph-container code-font"><a href="5-cg.html#SP20_3_1" class="named-paragraph-link"><span class="named-paragraph">It is now evident that the lines have incompatible determination types</span><span class="named-paragraph-number">20.3.1</span></a></span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">break</span><span class="plain-syntax">; </span><span class="comment-syntax"> to prevent the problem being repeated for the same grammar</span>
|
|
<span class="plain-syntax"> }</span>
|
|
<span class="plain-syntax"> }</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">LOG_OUTDENT</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">LOGIF</span><span class="plain-syntax">(</span><span class="identifier-syntax">GRAMMAR_CONSTRUCTION</span><span class="plain-syntax">, </span><span class="string-syntax">"Result is $P\n"</span><span class="plain-syntax">, </span><span class="identifier-syntax">spec_union</span><span class="plain-syntax">);</span>
|
|
</pre>
|
|
<ul class="endnotetexts"><li>This code is used in <a href="5-cg.html#SP20">§20</a>.</li></ul>
|
|
<p class="commentary firstcommentary"><a id="SP20_3_1" class="paragraph-anchor"></a><b>§20.3.1. </b>In some CGs, it doesn't matter if the lines do different things: for example,
|
|
in the CG_IS_COMMAND for the command verb TAKE, "inventory" (void determination
|
|
type) and "[things]" (single term determination type) can happily co-exist.
|
|
</p>
|
|
|
|
<p class="commentary">CG_IS_VALUE and CG_IS_SUBJECT are also exceptions because they include grammars
|
|
associated with kinds, in which different CGLs may describe different specific
|
|
values of that kind. For example, the one for the kind <span class="extract"><span class="extract-syntax">K_number</span></span> might have one
|
|
CGL describing the number 17, and another describing 22. There's no good way to
|
|
take the union of those numbers.
|
|
</p>
|
|
|
|
<p class="commentary"><span class="named-paragraph-container code-font"><span class="named-paragraph-defn">It is now evident that the lines have incompatible determination types</span><span class="named-paragraph-number">20.3.1</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">cg</span><span class="plain-syntax">-></span><span class="element-syntax">cg_is</span><span class="plain-syntax"> == </span><span class="constant-syntax">CG_IS_CONSULT</span><span class="plain-syntax">) ||</span>
|
|
<span class="plain-syntax"> (</span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">cg_is</span><span class="plain-syntax"> == </span><span class="constant-syntax">CG_IS_SUBJECT</span><span class="plain-syntax">) ||</span>
|
|
<span class="plain-syntax"> (</span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">cg_is</span><span class="plain-syntax"> == </span><span class="constant-syntax">CG_IS_COMMAND</span><span class="plain-syntax">) ||</span>
|
|
<span class="plain-syntax"> (</span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">cg_is</span><span class="plain-syntax"> == </span><span class="constant-syntax">CG_IS_VALUE</span><span class="plain-syntax">)) </span><span class="reserved-syntax">continue</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">current_sentence</span><span class="plain-syntax"> = </span><span class="identifier-syntax">cgl</span><span class="plain-syntax">-></span><span class="element-syntax">where_grammar_specified</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">LOG</span><span class="plain-syntax">(</span><span class="string-syntax">"Offending CGL is $g in $G\n"</span><span class="plain-syntax">, </span><span class="identifier-syntax">cgl</span><span class="plain-syntax">, </span><span class="identifier-syntax">cg</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_MixedOutcome</span><span class="plain-syntax">),</span>
|
|
<span class="plain-syntax"> </span><span class="string-syntax">"grammar tokens must have the same outcome whatever the way they are reached"</span><span class="plain-syntax">,</span>
|
|
<span class="plain-syntax"> </span><span class="string-syntax">"so writing a line like 'Understand \"within\" or \"next to [something]\" "</span>
|
|
<span class="plain-syntax"> </span><span class="string-syntax">"as \"[my token]\" must be wrong: one way it produces a thing, the other "</span>
|
|
<span class="plain-syntax"> </span><span class="string-syntax">"way it doesn't."</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">spec_union</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="5-cg.html#SP20_3">§20.3</a>.</li></ul>
|
|
<p class="commentary firstcommentary"><a id="SP20_4" class="paragraph-anchor"></a><b>§20.4. </b><span class="named-paragraph-container code-font"><span class="named-paragraph-defn">Cache the answer so that we need not determine it again</span><span class="named-paragraph-number">20.4</span></span><span class="comment-syntax"> =</span>
|
|
</p>
|
|
|
|
<pre class="displayed-code all-displayed-code code-font">
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">determined</span><span class="plain-syntax"> = </span><span class="identifier-syntax">TRUE</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><a href="5-dt.html#SP4" class="function-link"><span class="function-syntax">DeterminationTypes::set_single_term</span></a><span class="plain-syntax">(&(</span><span class="identifier-syntax">cg</span><span class="plain-syntax">-></span><span class="element-syntax">cg_type</span><span class="plain-syntax">), </span><span class="identifier-syntax">spec_union</span><span class="plain-syntax">);</span>
|
|
</pre>
|
|
<ul class="endnotetexts"><li>This code is used in <a href="5-cg.html#SP20">§20</a>.</li></ul>
|
|
<p class="commentary firstcommentary"><a id="SP21" class="paragraph-anchor"></a><b>§21. Sorting. </b>The list of lines in a CG needs to be sorted into order before compilation,
|
|
to ensure that the player's commands are interpreted correctly whatever order
|
|
in which the designer wrote the "Understand... as..." sentences setting it up.
|
|
</p>
|
|
|
|
<p class="commentary">Note that some grammars are compiled more than once, but that we only want to
|
|
sort once, so:
|
|
</p>
|
|
|
|
<pre class="displayed-code all-displayed-code code-font">
|
|
<span class="reserved-syntax">void</span><span class="plain-syntax"> </span><span class="function-syntax">CommandGrammars::sort_command_grammar</span><span class="plain-syntax">(</span><span class="reserved-syntax">command_grammar</span><span class="plain-syntax"> *</span><span class="identifier-syntax">cg</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">cg</span><span class="plain-syntax">-></span><span class="element-syntax">sorted_first_line</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">cg</span><span class="plain-syntax">-></span><span class="element-syntax">sorted_first_line</span><span class="plain-syntax"> = </span><a href="5-cgl.html#SP17" class="function-link"><span class="function-syntax">CGLines::list_sort</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">cg</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-us.html">❮</a></li><li class="progresschapter"><a href="P-wtmd.html">P</a></li><li class="progresschapter"><a href="1-im.html">1</a></li><li class="progresschapter"><a href="2-bd.html">2</a></li><li class="progresschapter"><a href="3-sm.html">3</a></li><li class="progresschapter"><a href="4-ap.html">4</a></li><li class="progresscurrentchapter">5</li><li class="progresssection"><a href="5-pp.html">pp</a></li><li class="progresssection"><a href="5-us.html">us</a></li><li class="progresscurrent">cg</li><li class="progresssection"><a href="5-cgl.html">cgl</a></li><li class="progresssection"><a href="5-cgt.html">cgt</a></li><li class="progresssection"><a href="5-dt.html">dt</a></li><li class="progresssection"><a href="5-pv.html">pv</a></li><li class="progresssection"><a href="5-ts.html">ts</a></li><li class="progresschapter"><a href="6-dlg.html">6</a></li><li class="progressnext"><a href="5-cgl.html">❯</a></li></ul></div>
|
|
</nav><!--End of weave-->
|
|
|
|
</main>
|
|
</body>
|
|
</html>
|
|
|