1
0
Fork 0
mirror of https://github.com/ganelson/inform.git synced 2024-05-19 09:28:51 +03:00
inform7/docs/runtime-module/4-bq.html

168 lines
23 KiB
HTML

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<title>Box Quotations</title>
<link href="../docs-assets/Breadcrumbs.css" rel="stylesheet" rev="stylesheet" type="text/css">
<meta name="viewport" content="width=device-width initial-scale=1">
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<meta http-equiv="Content-Language" content="en-gb">
<link href="../docs-assets/Contents.css" rel="stylesheet" rev="stylesheet" type="text/css">
<link href="../docs-assets/Progress.css" rel="stylesheet" rev="stylesheet" type="text/css">
<link href="../docs-assets/Navigation.css" rel="stylesheet" rev="stylesheet" type="text/css">
<link href="../docs-assets/Fonts.css" rel="stylesheet" rev="stylesheet" type="text/css">
<link href="../docs-assets/Base.css" rel="stylesheet" rev="stylesheet" type="text/css">
<script>
function togglePopup(material_id) {
var popup = document.getElementById(material_id);
popup.classList.toggle("show");
}
</script>
<link href="../docs-assets/Popups.css" rel="stylesheet" rev="stylesheet" type="text/css">
<link href="../docs-assets/Colours.css" rel="stylesheet" rev="stylesheet" type="text/css">
</head>
<body class="commentary-font">
<nav role="navigation">
<h1><a href="../index.html">
<img src="../docs-assets/Inform.png" height=72">
</a></h1>
<ul><li><a href="../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>
</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 'Box Quotations' 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">runtime</a></li><li><a href="index.html#4">Chapter 4: Enclosed Resources</a></li><li><b>Box Quotations</b></li></ul></div>
<p class="purpose">In this section we compile text constants.</p>
<p class="commentary firstcommentary"><a id="SP1" class="paragraph-anchor"></a><b>&#167;1. </b>It's a little strange to be writing, in 2012, code to handle an
idiosyncratic one-off form of text called a "quotation", just to match an
idiosyncratic feature of Inform 1 from 1993 which was in turn matching an
idiosyncratic feature of version 4 of the Z-machine from 1985 which, in turn,
existed only to serve the needs of an unusual single work of IF called
"Trinity". But here we are.
</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">box_quotation</span><span class="plain-syntax"> {</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">struct</span><span class="plain-syntax"> </span><span class="identifier-syntax">inter_name</span><span class="plain-syntax"> *</span><span class="identifier-syntax">function_iname</span><span class="plain-syntax">;</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">struct</span><span class="plain-syntax"> </span><span class="identifier-syntax">inter_name</span><span class="plain-syntax"> *</span><span class="identifier-syntax">seen_flag_iname</span><span class="plain-syntax">;</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">struct</span><span class="plain-syntax"> </span><span class="identifier-syntax">text_stream</span><span class="plain-syntax"> *</span><span class="identifier-syntax">content</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">function_compiled</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">box_quotation</span><span class="plain-syntax">;</span>
<span class="reserved-syntax">void</span><span class="plain-syntax"> </span><span class="function-syntax">BoxQuotations::new</span><span class="plain-syntax">(</span><span class="identifier-syntax">value_holster</span><span class="plain-syntax"> *</span><span class="identifier-syntax">VH</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">box_quotation</span><span class="plain-syntax"> *</span><span class="identifier-syntax">bq</span><span class="plain-syntax"> = </span><span class="identifier-syntax">CREATE</span><span class="plain-syntax">(</span><span class="reserved-syntax">box_quotation</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">bq</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">function_iname</span><span class="plain-syntax"> = </span><a href="4-enc.html#SP1" class="function-link"><span class="function-syntax">Enclosures::new_iname</span></a><span class="plain-syntax">(</span><span class="constant-syntax">BOX_QUOTATIONS_HAP</span><span class="plain-syntax">, </span><span class="constant-syntax">BOX_QUOTATION_FN_HL</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">bq</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">seen_flag_iname</span><span class="plain-syntax"> = </span><a href="4-enc.html#SP1" class="function-link"><span class="function-syntax">Enclosures::new_iname</span></a><span class="plain-syntax">(</span><span class="constant-syntax">BOX_QUOTATIONS_HAP</span><span class="plain-syntax">, </span><span class="constant-syntax">BOX_FLAG_HL</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">bq</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">function_compiled</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">bq</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">content</span><span class="plain-syntax"> = </span><span class="identifier-syntax">Str::new</span><span class="plain-syntax">();</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">TranscodeText::bq_from_wide_string</span><span class="plain-syntax">(</span><span class="identifier-syntax">bq</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">content</span><span class="plain-syntax">, </span><span class="identifier-syntax">Lexer::word_text</span><span class="plain-syntax">(</span><span class="identifier-syntax">Wordings::first_wn</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">Str::len</span><span class="plain-syntax">(</span><span class="identifier-syntax">bq</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">content</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">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_EmptyQuotationBox</span><span class="plain-syntax">),</span>
<span class="plain-syntax"> </span><span class="string-syntax">"a boxed quotation can't be empty"</span><span class="plain-syntax">,</span>
<span class="plain-syntax"> </span><span class="string-syntax">"though I suppose you could make it consist of just a few spaces "</span>
<span class="plain-syntax"> </span><span class="string-syntax">"to get a similar effect if you really needed to."</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">text_stream</span><span class="plain-syntax"> *</span><span class="identifier-syntax">desc</span><span class="plain-syntax"> = </span><span class="identifier-syntax">Str::new</span><span class="plain-syntax">();</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">WRITE_TO</span><span class="plain-syntax">(</span><span class="identifier-syntax">desc</span><span class="plain-syntax">, </span><span class="string-syntax">"box quotation '%W'"</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">Sequence::queue</span><span class="plain-syntax">(&amp;</span><a href="4-bq.html#SP2" class="function-link"><span class="function-syntax">BoxQuotations::compilation_agent</span></a><span class="plain-syntax">, </span><span class="identifier-syntax">STORE_POINTER_box_quotation</span><span class="plain-syntax">(</span><span class="identifier-syntax">bq</span><span class="plain-syntax">), </span><span class="identifier-syntax">desc</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">VH</span><span class="plain-syntax">) </span><a href="2-emt.html#SP2" class="function-link"><span class="function-syntax">Emit::holster_iname</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">VH</span><span class="plain-syntax">, </span><span class="identifier-syntax">bq</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">function_iname</span><span class="plain-syntax">);</span>
<span class="plain-syntax">}</span>
</pre>
<ul class="endnotetexts"><li>The structure box_quotation is accessed in 3/uo, 5/lp and here.</li></ul>
<p class="commentary firstcommentary"><a id="SP2" class="paragraph-anchor"></a><b>&#167;2. </b>The box functions are then compiled in due course by the following agent
(see <a href="../core-module/1-htc.html" class="internal">How To Compile (in core)</a>). The reason they weren't simply compiled earlier
is that a function was already being compiled at the time, and you can't
compile two functions at the same time.
</p>
<p class="commentary">The "box function", which displays the quotation, roughly translates to:
</p>
<pre class="displayed-code all-displayed-code code-font">
<span class="plain-syntax"> if (flag == false) {</span>
<span class="plain-syntax"> flag = true;</span>
<span class="plain-syntax"> box "The quotation here.";</span>
<span class="plain-syntax"> }</span>
</pre>
<p class="commentary">and ensures that the quotation displays only once. The flag is stored as a
tiny array inside the same enclosure as the box function.
</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">BoxQuotations::compilation_agent</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">BoxQuotations::compilation_agent</span></span>:<br/><a href="4-bq.html#SP1">&#167;1</a></span></button><span class="plain-syntax">(</span><span class="identifier-syntax">compilation_subtask</span><span class="plain-syntax"> *</span><span class="identifier-syntax">t</span><span class="plain-syntax">) {</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">box_quotation</span><span class="plain-syntax"> *</span><span class="identifier-syntax">bq</span><span class="plain-syntax"> = </span><span class="identifier-syntax">RETRIEVE_POINTER_box_quotation</span><span class="plain-syntax">(</span><span class="identifier-syntax">t</span><span class="plain-syntax">-&gt;</span><span class="identifier-syntax">data</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">packaging_state</span><span class="plain-syntax"> </span><span class="identifier-syntax">save</span><span class="plain-syntax"> = </span><a href="2-ea.html#SP2" class="function-link"><span class="function-syntax">EmitArrays::begin_word</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">bq</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">seen_flag_iname</span><span class="plain-syntax">, </span><span class="identifier-syntax">K_number</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><a href="2-ea.html#SP4" class="function-link"><span class="function-syntax">EmitArrays::numeric_entry</span></a><span class="plain-syntax">(0);</span>
<span class="plain-syntax"> </span><a href="2-ea.html#SP4" class="function-link"><span class="function-syntax">EmitArrays::numeric_entry</span></a><span class="plain-syntax">(0);</span>
<span class="plain-syntax"> </span><a href="2-ea.html#SP5" class="function-link"><span class="function-syntax">EmitArrays::end</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">save</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">save</span><span class="plain-syntax"> = </span><span class="identifier-syntax">Functions::begin</span><span class="plain-syntax">(</span><span class="identifier-syntax">bq</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">function_iname</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><a href="2-ec.html#SP14" class="function-link"><span class="function-syntax">EmitCode::inv</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">IF_BIP</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><a href="2-ec.html#SP3" class="function-link"><span class="function-syntax">EmitCode::down</span></a><span class="plain-syntax">();</span>
<span class="plain-syntax"> </span><a href="2-ec.html#SP14" class="function-link"><span class="function-syntax">EmitCode::inv</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">EQ_BIP</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><a href="2-ec.html#SP3" class="function-link"><span class="function-syntax">EmitCode::down</span></a><span class="plain-syntax">();</span>
<span class="plain-syntax"> </span><a href="2-ec.html#SP14" class="function-link"><span class="function-syntax">EmitCode::inv</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">LOOKUP_BIP</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><a href="2-ec.html#SP3" class="function-link"><span class="function-syntax">EmitCode::down</span></a><span class="plain-syntax">();</span>
<span class="plain-syntax"> </span><a href="2-ec.html#SP8" class="function-link"><span class="function-syntax">EmitCode::val_iname</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">K_value</span><span class="plain-syntax">, </span><span class="identifier-syntax">bq</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">seen_flag_iname</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><a href="2-ec.html#SP8" class="function-link"><span class="function-syntax">EmitCode::val_number</span></a><span class="plain-syntax">(0);</span>
<span class="plain-syntax"> </span><a href="2-ec.html#SP3" class="function-link"><span class="function-syntax">EmitCode::up</span></a><span class="plain-syntax">();</span>
<span class="plain-syntax"> </span><a href="2-ec.html#SP8" class="function-link"><span class="function-syntax">EmitCode::val_number</span></a><span class="plain-syntax">(0);</span>
<span class="plain-syntax"> </span><a href="2-ec.html#SP3" class="function-link"><span class="function-syntax">EmitCode::up</span></a><span class="plain-syntax">();</span>
<span class="plain-syntax"> </span><a href="2-ec.html#SP5" class="function-link"><span class="function-syntax">EmitCode::code</span></a><span class="plain-syntax">();</span>
<span class="plain-syntax"> </span><a href="2-ec.html#SP3" class="function-link"><span class="function-syntax">EmitCode::down</span></a><span class="plain-syntax">();</span>
<span class="plain-syntax"> </span><a href="2-ec.html#SP14" class="function-link"><span class="function-syntax">EmitCode::inv</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">STORE_BIP</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><a href="2-ec.html#SP3" class="function-link"><span class="function-syntax">EmitCode::down</span></a><span class="plain-syntax">();</span>
<span class="plain-syntax"> </span><a href="2-ec.html#SP5" class="function-link"><span class="function-syntax">EmitCode::reference</span></a><span class="plain-syntax">();</span>
<span class="plain-syntax"> </span><a href="2-ec.html#SP3" class="function-link"><span class="function-syntax">EmitCode::down</span></a><span class="plain-syntax">();</span>
<span class="plain-syntax"> </span><a href="2-ec.html#SP14" class="function-link"><span class="function-syntax">EmitCode::inv</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">LOOKUP_BIP</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><a href="2-ec.html#SP3" class="function-link"><span class="function-syntax">EmitCode::down</span></a><span class="plain-syntax">();</span>
<span class="plain-syntax"> </span><a href="2-ec.html#SP8" class="function-link"><span class="function-syntax">EmitCode::val_iname</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">K_value</span><span class="plain-syntax">, </span><span class="identifier-syntax">bq</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">seen_flag_iname</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><a href="2-ec.html#SP8" class="function-link"><span class="function-syntax">EmitCode::val_number</span></a><span class="plain-syntax">(0);</span>
<span class="plain-syntax"> </span><a href="2-ec.html#SP3" class="function-link"><span class="function-syntax">EmitCode::up</span></a><span class="plain-syntax">();</span>
<span class="plain-syntax"> </span><a href="2-ec.html#SP3" class="function-link"><span class="function-syntax">EmitCode::up</span></a><span class="plain-syntax">();</span>
<span class="plain-syntax"> </span><a href="2-ec.html#SP8" class="function-link"><span class="function-syntax">EmitCode::val_number</span></a><span class="plain-syntax">(1);</span>
<span class="plain-syntax"> </span><a href="2-ec.html#SP3" class="function-link"><span class="function-syntax">EmitCode::up</span></a><span class="plain-syntax">();</span>
<span class="plain-syntax"> </span><a href="2-ec.html#SP14" class="function-link"><span class="function-syntax">EmitCode::inv</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">BOX_BIP</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><a href="2-ec.html#SP3" class="function-link"><span class="function-syntax">EmitCode::down</span></a><span class="plain-syntax">();</span>
<span class="plain-syntax"> </span><a href="2-ec.html#SP8" class="function-link"><span class="function-syntax">EmitCode::val_text</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">bq</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">content</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><a href="2-ec.html#SP3" class="function-link"><span class="function-syntax">EmitCode::up</span></a><span class="plain-syntax">();</span>
<span class="plain-syntax"> </span><a href="2-ec.html#SP3" class="function-link"><span class="function-syntax">EmitCode::up</span></a><span class="plain-syntax">();</span>
<span class="plain-syntax"> </span><a href="2-ec.html#SP3" class="function-link"><span class="function-syntax">EmitCode::up</span></a><span class="plain-syntax">();</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">Functions::end</span><span class="plain-syntax">(</span><span class="identifier-syntax">save</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="4-rsp.html">&#10094;</a></li><li class="progresschapter"><a href="P-wtmd.html">P</a></li><li class="progresschapter"><a href="1-rm.html">1</a></li><li class="progresschapter"><a href="2-hrr.html">2</a></li><li class="progresschapter"><a href="3-gm.html">3</a></li><li class="progresscurrentchapter">4</li><li class="progresssection"><a href="4-enc.html">enc</a></li><li class="progresssection"><a href="4-ll.html">ll</a></li><li class="progresssection"><a href="4-tl.html">tl</a></li><li class="progresssection"><a href="4-ts.html">ts</a></li><li class="progresssection"><a href="4-rsp.html">rsp</a></li><li class="progresscurrent">bq</li><li class="progresssection"><a href="4-rl.html">rl</a></li><li class="progresssection"><a href="4-sal.html">sal</a></li><li class="progresssection"><a href="4-gt.html">gt</a></li><li class="progresssection"><a href="4-los.html">los</a></li><li class="progresschapter"><a href="5-act.html">5</a></li><li class="progresschapter"><a href="6-bd.html">6</a></li><li class="progresschapter"><a href="7-cg.html">7</a></li><li class="progressnext"><a href="4-rl.html">&#10095;</a></li></ul></div>
</nav><!--End of weave-->
</main>
</body>
</html>