ifhub/inform7
1
0
Fork 0
mirror of https://github.com/ganelson/inform.git synced 2024-07-05 00:24:22 +03:00
Code Issues Projects Releases Wiki Activity
inform7/docs/final-module/4-i6c.html
Graham Nelson 46349cb85c Fix for Jira bug I7-2269
2023-01-01 22:29:11 +00:00

601 lines
118 KiB
HTML
Raw Blame History

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<title>Inform 6 Constants</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>
<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 'Inform 6 Constants' generated by Inweb-->
<div class="breadcrumbs">
<ul class="crumbs"><li><a href="../index.html">Home</a></li><li><a href="../intern.html">Inter Modules</a></li><li><a href="index.html">final</a></li><li><a href="index.html#4">Chapter 4: Inform 6</a></li><li><b>Inform 6 Constants</b></li></ul></div>
<p class="purpose">To declare I6 constants and arrays.</p>
<ul class="toc"><li><a href="4-i6c.html#SP2">&#167;2. Constant values</a></li><li><a href="4-i6c.html#SP3">&#167;3. Arrays</a></li><li><a href="4-i6c.html#SP5">&#167;5. Actions</a></li><li><a href="4-i6c.html#SP6">&#167;6. Literals</a></li></ul><hr class="tocbar">
<p class="commentary firstcommentary"><a id="SP1" class="paragraph-anchor"></a><b>&#167;1. </b></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">I6TargetConstants::create_generator</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">I6TargetConstants::create_generator</span></span>:<br/>Generating Inform 6 - <a href="4-fi6.html#SP1">&#167;1</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">code_generator</span><span class="plain-syntax"> *</span><span class="identifier-syntax">gtr</span><span class="plain-syntax">) {</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">METHOD_ADD</span><span class="plain-syntax">(</span><span class="identifier-syntax">gtr</span><span class="plain-syntax">, </span><span class="constant-syntax">DECLARE_CONSTANT_MTID</span><span class="plain-syntax">, </span><a href="4-i6c.html#SP2" class="function-link"><span class="function-syntax">I6TargetConstants::declare_constant</span></a><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">METHOD_ADD</span><span class="plain-syntax">(</span><span class="identifier-syntax">gtr</span><span class="plain-syntax">, </span><span class="constant-syntax">BEGIN_ARRAY_MTID</span><span class="plain-syntax">, </span><a href="4-i6c.html#SP3" class="function-link"><span class="function-syntax">I6TargetConstants::begin_array</span></a><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">METHOD_ADD</span><span class="plain-syntax">(</span><span class="identifier-syntax">gtr</span><span class="plain-syntax">, </span><span class="constant-syntax">ARRAY_ENTRY_MTID</span><span class="plain-syntax">, </span><a href="4-i6c.html#SP4" class="function-link"><span class="function-syntax">I6TargetConstants::array_entry</span></a><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">METHOD_ADD</span><span class="plain-syntax">(</span><span class="identifier-syntax">gtr</span><span class="plain-syntax">, </span><span class="constant-syntax">END_ARRAY_MTID</span><span class="plain-syntax">, </span><a href="4-i6c.html#SP4" class="function-link"><span class="function-syntax">I6TargetConstants::end_array</span></a><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">METHOD_ADD</span><span class="plain-syntax">(</span><span class="identifier-syntax">gtr</span><span class="plain-syntax">, </span><span class="constant-syntax">NEW_ACTION_MTID</span><span class="plain-syntax">, </span><a href="4-i6c.html#SP5" class="function-link"><span class="function-syntax">I6TargetConstants::new_action</span></a><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">METHOD_ADD</span><span class="plain-syntax">(</span><span class="identifier-syntax">gtr</span><span class="plain-syntax">, </span><span class="constant-syntax">COMPILE_DICTIONARY_WORD_MTID</span><span class="plain-syntax">, </span><a href="4-i6c.html#SP7" class="function-link"><span class="function-syntax">I6TargetConstants::compile_dictionary_word</span></a><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">METHOD_ADD</span><span class="plain-syntax">(</span><span class="identifier-syntax">gtr</span><span class="plain-syntax">, </span><span class="constant-syntax">COMPILE_LITERAL_NUMBER_MTID</span><span class="plain-syntax">, </span><a href="4-i6c.html#SP6" class="function-link"><span class="function-syntax">I6TargetConstants::compile_literal_number</span></a><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">METHOD_ADD</span><span class="plain-syntax">(</span><span class="identifier-syntax">gtr</span><span class="plain-syntax">, </span><span class="constant-syntax">COMPILE_LITERAL_REAL_MTID</span><span class="plain-syntax">, </span><a href="4-i6c.html#SP6" class="function-link"><span class="function-syntax">I6TargetConstants::compile_literal_real</span></a><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">METHOD_ADD</span><span class="plain-syntax">(</span><span class="identifier-syntax">gtr</span><span class="plain-syntax">, </span><span class="constant-syntax">COMPILE_LITERAL_TEXT_MTID</span><span class="plain-syntax">, </span><a href="4-i6c.html#SP8" class="function-link"><span class="function-syntax">I6TargetConstants::compile_literal_text</span></a><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">METHOD_ADD</span><span class="plain-syntax">(</span><span class="identifier-syntax">gtr</span><span class="plain-syntax">, </span><span class="constant-syntax">COMPILE_LITERAL_SYMBOL_MTID</span><span class="plain-syntax">, </span><a href="4-i6c.html#SP9" class="function-link"><span class="function-syntax">I6TargetConstants::compile_literal_symbol</span></a><span class="plain-syntax">);</span>
<span class="plain-syntax">}</span>
</pre>
<p class="commentary firstcommentary"><a id="SP2" class="paragraph-anchor"></a><b>&#167;2. Constant values. </b>Constants are layered by depth, so that if the initial value for <span class="extract"><span class="extract-syntax">X</span></span> depends
on that for <span class="extract"><span class="extract-syntax">Y</span></span> then the declaration for <span class="extract"><span class="extract-syntax">Y</span></span> will always be placed earlier in the
code than that for <span class="extract"><span class="extract-syntax">X</span></span>. See <a href="2-cg.html" class="internal">Code Generation</a> for how this is done.
</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">I6TargetConstants::declare_constant</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">I6TargetConstants::declare_constant</span></span>:<br/><a href="4-i6c.html#SP1">&#167;1</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">code_generator</span><span class="plain-syntax"> *</span><span class="identifier-syntax">gtr</span><span class="plain-syntax">, </span><span class="reserved-syntax">code_generation</span><span class="plain-syntax"> *</span><span class="identifier-syntax">gen</span><span class="plain-syntax">,</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">inter_symbol</span><span class="plain-syntax"> *</span><span class="identifier-syntax">const_s</span><span class="plain-syntax">, </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">form</span><span class="plain-syntax">, </span><span class="identifier-syntax">text_stream</span><span class="plain-syntax"> *</span><span class="identifier-syntax">val</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">const_name</span><span class="plain-syntax"> = </span><span class="identifier-syntax">InterSymbol::trans</span><span class="plain-syntax">(</span><span class="identifier-syntax">const_s</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="named-paragraph-container code-font"><a href="4-i6c.html#SP2_1" class="named-paragraph-link"><span class="named-paragraph">Leave undeclared any array used as a value of a property</span><span class="named-paragraph-number">2.1</span></a></span><span class="plain-syntax">;</span>
<span class="plain-syntax"> </span><span class="named-paragraph-container code-font"><a href="4-i6c.html#SP2_2" class="named-paragraph-link"><span class="named-paragraph">Leave undeclared any constant auto-declared by the I6 compiler</span><span class="named-paragraph-number">2.2</span></a></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">depth</span><span class="plain-syntax"> = </span><span class="constant-syntax">1</span><span class="plain-syntax">;</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">const_s</span><span class="plain-syntax">) </span><span class="identifier-syntax">depth</span><span class="plain-syntax"> = </span><span class="identifier-syntax">ConstantInstruction::constant_depth</span><span class="plain-syntax">(</span><span class="identifier-syntax">const_s</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">segmentation_pos</span><span class="plain-syntax"> </span><span class="identifier-syntax">saved</span><span class="plain-syntax"> = </span><a href="2-cg.html#SP12" class="function-link"><span class="function-syntax">CodeGen::select_layered</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">gen</span><span class="plain-syntax">, </span><span class="constant-syntax">constants_I7CGS</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">text_stream</span><span class="plain-syntax"> *</span><span class="identifier-syntax">OUT</span><span class="plain-syntax"> = </span><a href="2-cg.html#SP14" class="function-link"><span class="function-syntax">CodeGen::current</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">gen</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::eq</span><span class="plain-syntax">(</span><span class="identifier-syntax">const_name</span><span class="plain-syntax">, </span><span class="identifier-syntax">I</span><span class="string-syntax">"Release"</span><span class="plain-syntax">)) </span><span class="named-paragraph-container code-font"><a href="4-i6c.html#SP2_4" class="named-paragraph-link"><span class="named-paragraph">Declare the Release constant with a directive</span><span class="named-paragraph-number">2.4</span></a></span><span class="plain-syntax">;</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">Str::eq</span><span class="plain-syntax">(</span><span class="identifier-syntax">const_name</span><span class="plain-syntax">, </span><span class="identifier-syntax">I</span><span class="string-syntax">"Serial"</span><span class="plain-syntax">)) </span><span class="named-paragraph-container code-font"><a href="4-i6c.html#SP2_5" class="named-paragraph-link"><span class="named-paragraph">Declare the Serial constant with a directive</span><span class="named-paragraph-number">2.5</span></a></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">ifndef_me</span><span class="plain-syntax"> = </span><span class="identifier-syntax">FALSE</span><span class="plain-syntax">;</span>
<span class="plain-syntax"> </span><span class="named-paragraph-container code-font"><a href="4-i6c.html#SP2_3" class="named-paragraph-link"><span class="named-paragraph">Certain constants should be declared only if I6 has not already declared them</span><span class="named-paragraph-number">2.3</span></a></span><span class="plain-syntax">;</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">ifndef_me</span><span class="plain-syntax">) </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"#ifndef %S;\n"</span><span class="plain-syntax">, </span><span class="identifier-syntax">const_name</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"Constant %S = "</span><span class="plain-syntax">, </span><span class="identifier-syntax">const_name</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><a href="2-vc.html#SP2" class="function-link"><span class="function-syntax">VanillaConstants::definition_value</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">gen</span><span class="plain-syntax">, </span><span class="identifier-syntax">form</span><span class="plain-syntax">, </span><span class="identifier-syntax">const_s</span><span class="plain-syntax">, </span><span class="identifier-syntax">val</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">";\n"</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">ifndef_me</span><span class="plain-syntax">) </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"#endif;\n"</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><a href="2-cg.html#SP12" class="function-link"><span class="function-syntax">CodeGen::deselect</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">gen</span><span class="plain-syntax">, </span><span class="identifier-syntax">saved</span><span class="plain-syntax">);</span>
<span class="plain-syntax">}</span>
</pre>
<p class="commentary firstcommentary"><a id="SP2_1" class="paragraph-anchor"></a><b>&#167;2.1. </b>A curious feature of Inform, going back to the original 1970s design of the
Z-machine VM, is that properties of objects can be small arrays rather than
single values. These are, for some reason, called "inline arrays". The I6
generator is going to take advantage of this feature: if it sees that a
property is actually an address of a small array, it will compile that array
directly into the body of the relevant object or class declaration. It therefore
does not need to declare the name of this small array, and so &mdash;
</p>
<p class="commentary"><span class="named-paragraph-container code-font"><span class="named-paragraph-defn">Leave undeclared any array used as a value of a property</span><span class="named-paragraph-number">2.1</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">ConstantInstruction::is_inline</span><span class="plain-syntax">(</span><span class="identifier-syntax">const_s</span><span class="plain-syntax">))</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax">;</span>
</pre>
<ul class="endnotetexts"><li>This code is used in <a href="4-i6c.html#SP2">&#167;2</a>.</li></ul>
<p class="commentary firstcommentary"><a id="SP2_2" class="paragraph-anchor"></a><b>&#167;2.2. </b>We cannot declare these constants because they exist automatically, and
declaring them will therefore throw an error message calling them duplicates.
(The initial values these have in the Inter tree are perfectly correct, and on
other targets they will be compiled normally.)
</p>
<p class="commentary">The <span class="extract"><span class="extract-syntax">FLOAT_*</span></span> constants are defined only when I6 compiles to the Glulx VM,
but then, they are only present in the Inter tree when we are headed that way
anyway.
</p>
<p class="commentary"><span class="named-paragraph-container code-font"><span class="named-paragraph-defn">Leave undeclared any constant auto-declared by the I6 compiler</span><span class="named-paragraph-number">2.2</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">Str::eq</span><span class="plain-syntax">(</span><span class="identifier-syntax">const_name</span><span class="plain-syntax">, </span><span class="identifier-syntax">I</span><span class="string-syntax">"FLOAT_INFINITY"</span><span class="plain-syntax">)) ||</span>
<span class="plain-syntax"> (</span><span class="identifier-syntax">Str::eq</span><span class="plain-syntax">(</span><span class="identifier-syntax">const_name</span><span class="plain-syntax">, </span><span class="identifier-syntax">I</span><span class="string-syntax">"FLOAT_NINFINITY"</span><span class="plain-syntax">)) ||</span>
<span class="plain-syntax"> (</span><span class="identifier-syntax">Str::eq</span><span class="plain-syntax">(</span><span class="identifier-syntax">const_name</span><span class="plain-syntax">, </span><span class="identifier-syntax">I</span><span class="string-syntax">"FLOAT_NAN"</span><span class="plain-syntax">)) ||</span>
<span class="plain-syntax"> (</span><span class="identifier-syntax">Str::eq</span><span class="plain-syntax">(</span><span class="identifier-syntax">const_name</span><span class="plain-syntax">, </span><span class="identifier-syntax">I</span><span class="string-syntax">"nothing"</span><span class="plain-syntax">)) ||</span>
<span class="plain-syntax"> (</span><span class="identifier-syntax">Str::eq</span><span class="plain-syntax">(</span><span class="identifier-syntax">const_name</span><span class="plain-syntax">, </span><span class="identifier-syntax">I</span><span class="string-syntax">"#dict_par1"</span><span class="plain-syntax">)) ||</span>
<span class="plain-syntax"> (</span><span class="identifier-syntax">Str::eq</span><span class="plain-syntax">(</span><span class="identifier-syntax">const_name</span><span class="plain-syntax">, </span><span class="identifier-syntax">I</span><span class="string-syntax">"#dict_par2"</span><span class="plain-syntax">)))</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax">;</span>
</pre>
<ul class="endnotetexts"><li>This code is used in <a href="4-i6c.html#SP2">&#167;2</a>.</li></ul>
<p class="commentary firstcommentary"><a id="SP2_3" class="paragraph-anchor"></a><b>&#167;2.3. </b>In addition to those are constants which are only sometimes auto-declared,
depending on, for example, the choice of virtual machine I6 is compiling to.
Some of this goes back to the fact that support for the Glulx VM was a retrofit
to the I6 compiler some years after its original design: there was no need for
a <span class="extract"><span class="extract-syntax">TARGET_ZCODE</span></span> constant back when Z-code was the only code it could make,
for example.
</p>
<p class="commentary"><span class="named-paragraph-container code-font"><span class="named-paragraph-defn">Certain constants should be declared only if I6 has not already declared them</span><span class="named-paragraph-number">2.3</span></span><span class="comment-syntax"> =</span>
</p>
<pre class="displayed-code all-displayed-code code-font">
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> ((</span><span class="identifier-syntax">Str::eq</span><span class="plain-syntax">(</span><span class="identifier-syntax">const_name</span><span class="plain-syntax">, </span><span class="identifier-syntax">I</span><span class="string-syntax">"WORDSIZE"</span><span class="plain-syntax">)) ||</span>
<span class="plain-syntax"> (</span><span class="identifier-syntax">Str::eq</span><span class="plain-syntax">(</span><span class="identifier-syntax">const_name</span><span class="plain-syntax">, </span><span class="identifier-syntax">I</span><span class="string-syntax">"TARGET_ZCODE"</span><span class="plain-syntax">)) ||</span>
<span class="plain-syntax"> (</span><span class="identifier-syntax">Str::eq</span><span class="plain-syntax">(</span><span class="identifier-syntax">const_name</span><span class="plain-syntax">, </span><span class="identifier-syntax">I</span><span class="string-syntax">"TARGET_GLULX"</span><span class="plain-syntax">)) ||</span>
<span class="plain-syntax"> (</span><span class="identifier-syntax">Str::eq</span><span class="plain-syntax">(</span><span class="identifier-syntax">const_name</span><span class="plain-syntax">, </span><span class="identifier-syntax">I</span><span class="string-syntax">"DICT_WORD_SIZE"</span><span class="plain-syntax">)) ||</span>
<span class="plain-syntax"> (</span><span class="identifier-syntax">Str::eq</span><span class="plain-syntax">(</span><span class="identifier-syntax">const_name</span><span class="plain-syntax">, </span><span class="identifier-syntax">I</span><span class="string-syntax">"DICT_ENTRY_BYTES"</span><span class="plain-syntax">)) ||</span>
<span class="plain-syntax"> (</span><span class="identifier-syntax">Str::eq</span><span class="plain-syntax">(</span><span class="identifier-syntax">const_name</span><span class="plain-syntax">, </span><span class="identifier-syntax">I</span><span class="string-syntax">"DEBUG"</span><span class="plain-syntax">)) ||</span>
<span class="plain-syntax"> (</span><span class="identifier-syntax">Str::eq</span><span class="plain-syntax">(</span><span class="identifier-syntax">const_name</span><span class="plain-syntax">, </span><span class="identifier-syntax">I</span><span class="string-syntax">"cap_short_name"</span><span class="plain-syntax">))) {</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">ifndef_me</span><span class="plain-syntax"> = </span><span class="identifier-syntax">TRUE</span><span class="plain-syntax">;</span>
<span class="plain-syntax"> }</span>
</pre>
<ul class="endnotetexts"><li>This code is used in <a href="4-i6c.html#SP2">&#167;2</a>.</li></ul>
<p class="commentary firstcommentary"><a id="SP2_4" class="paragraph-anchor"></a><b>&#167;2.4. </b>The release number is just another constant integer, but in I6 it has to be
declared with the <span class="extract"><span class="extract-syntax">Release</span></span> directive, so:
</p>
<p class="commentary"><span class="named-paragraph-container code-font"><span class="named-paragraph-defn">Declare the Release constant with a directive</span><span class="named-paragraph-number">2.4</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">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"Release "</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><a href="2-vc.html#SP2" class="function-link"><span class="function-syntax">VanillaConstants::definition_value</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">gen</span><span class="plain-syntax">, </span><span class="identifier-syntax">form</span><span class="plain-syntax">, </span><span class="identifier-syntax">const_s</span><span class="plain-syntax">, </span><span class="identifier-syntax">val</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">";\n"</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax">;</span>
</pre>
<ul class="endnotetexts"><li>This code is used in <a href="4-i6c.html#SP2">&#167;2</a>.</li></ul>
<p class="commentary firstcommentary"><a id="SP2_5" class="paragraph-anchor"></a><b>&#167;2.5. </b>Likewise the Serial code (e.g., <span class="extract"><span class="extract-syntax">"211010"</span></span>), which must be a double-quoted
literal:
</p>
<p class="commentary"><span class="named-paragraph-container code-font"><span class="named-paragraph-defn">Declare the Serial constant with a directive</span><span class="named-paragraph-number">2.5</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">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"Serial "</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><a href="2-vc.html#SP2" class="function-link"><span class="function-syntax">VanillaConstants::definition_value</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">gen</span><span class="plain-syntax">, </span><span class="identifier-syntax">form</span><span class="plain-syntax">, </span><span class="identifier-syntax">const_s</span><span class="plain-syntax">, </span><span class="identifier-syntax">val</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">";\n"</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax">;</span>
</pre>
<ul class="endnotetexts"><li>This code is used in <a href="4-i6c.html#SP2">&#167;2</a>.</li></ul>
<p class="commentary firstcommentary"><a id="SP3" class="paragraph-anchor"></a><b>&#167;3. Arrays. </b>Now for arrays, which we turn into <span class="extract"><span class="extract-syntax">Verb</span></span> or <span class="extract"><span class="extract-syntax">Array</span></span> directives in I6. We will
return <span class="extract"><span class="extract-syntax">FALSE</span></span> in the Verb case to tell Vanilla that the entire array has now
been declared, so it need do nothing further; <span class="extract"><span class="extract-syntax">TRUE</span></span> in the more typical <span class="extract"><span class="extract-syntax">Array</span></span>
case, whereupon Vanilla will lead us through the rest of the declaration.
</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">I6TargetConstants::begin_array</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">I6TargetConstants::begin_array</span></span>:<br/><a href="4-i6c.html#SP1">&#167;1</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">code_generator</span><span class="plain-syntax"> *</span><span class="identifier-syntax">gtr</span><span class="plain-syntax">, </span><span class="reserved-syntax">code_generation</span><span class="plain-syntax"> *</span><span class="identifier-syntax">gen</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">array_name</span><span class="plain-syntax">, </span><span class="identifier-syntax">inter_symbol</span><span class="plain-syntax"> *</span><span class="identifier-syntax">array_s</span><span class="plain-syntax">, </span><span class="identifier-syntax">inter_tree_node</span><span class="plain-syntax"> *</span><span class="identifier-syntax">P</span><span class="plain-syntax">, </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">format</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">zero_count</span><span class="plain-syntax">, </span><span class="reserved-syntax">segmentation_pos</span><span class="plain-syntax"> *</span><span class="identifier-syntax">saved</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">ConstantInstruction::list_format</span><span class="plain-syntax">(</span><span class="identifier-syntax">P</span><span class="plain-syntax">) == </span><span class="identifier-syntax">CONST_LIST_FORMAT_GRAMMAR</span><span class="plain-syntax">) {</span>
<span class="plain-syntax"> </span><span class="named-paragraph-container code-font"><a href="4-i6c.html#SP3_1" class="named-paragraph-link"><span class="named-paragraph">Write a complete I6 Verb directive</span><span class="named-paragraph-number">3.1</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">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="named-paragraph-container code-font"><a href="4-i6c.html#SP3_2" class="named-paragraph-link"><span class="named-paragraph">Begin an I6 Array directive</span><span class="named-paragraph-number">3.2</span></a></span><span class="plain-syntax">;</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">TRUE</span><span class="plain-syntax">;</span>
<span class="plain-syntax"> }</span>
<span class="plain-syntax">}</span>
</pre>
<p class="commentary firstcommentary"><a id="SP3_1" class="paragraph-anchor"></a><b>&#167;3.1. </b>Here we hijack a command-verb grammar array entirely. <span class="extract"><span class="extract-syntax">Verb</span></span> directives in I6
have a fruity sort of syntax, using reserved words not found elsewhere, and
punctuation markers like <span class="extract"><span class="extract-syntax">*</span></span> and <span class="extract"><span class="extract-syntax">-&gt;</span></span>, and constructs like <span class="extract"><span class="extract-syntax">scope=F</span></span> for functions
<span class="extract"><span class="extract-syntax">F</span></span>, and so on; so it's not really practical to create such directives as if
they were any other arrays. Here goes:
</p>
<p class="commentary"><span class="named-paragraph-container code-font"><span class="named-paragraph-defn">Write a complete I6 Verb directive</span><span class="named-paragraph-number">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">saved</span><span class="plain-syntax">) *</span><span class="identifier-syntax">saved</span><span class="plain-syntax"> = </span><a href="2-cg.html#SP12" class="function-link"><span class="function-syntax">CodeGen::select</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">gen</span><span class="plain-syntax">, </span><span class="constant-syntax">command_grammar_I7CGS</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">OUT</span><span class="plain-syntax"> = </span><a href="2-cg.html#SP14" class="function-link"><span class="function-syntax">CodeGen::current</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">gen</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"Verb"</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">marker</span><span class="plain-syntax"> = </span><span class="identifier-syntax">NOT_APPLICABLE</span><span class="plain-syntax">;</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">for</span><span class="plain-syntax"> (</span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">i</span><span class="plain-syntax">=0; </span><span class="identifier-syntax">i</span><span class="plain-syntax">&lt;</span><span class="identifier-syntax">ConstantInstruction::list_len</span><span class="plain-syntax">(</span><span class="identifier-syntax">P</span><span class="plain-syntax">); </span><span class="identifier-syntax">i</span><span class="plain-syntax">++) {</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">" "</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="identifier-syntax">val</span><span class="plain-syntax"> = </span><span class="identifier-syntax">ConstantInstruction::list_entry</span><span class="plain-syntax">(</span><span class="identifier-syntax">P</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">InterValuePairs::is_symbolic</span><span class="plain-syntax">(</span><span class="identifier-syntax">val</span><span class="plain-syntax">)) {</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">inter_symbol</span><span class="plain-syntax"> *</span><span class="identifier-syntax">A</span><span class="plain-syntax"> = </span><span class="identifier-syntax">InterValuePairs::to_symbol_at</span><span class="plain-syntax">(</span><span class="identifier-syntax">val</span><span class="plain-syntax">, </span><span class="identifier-syntax">P</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">A</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">"bad aliased symbol"</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">S</span><span class="plain-syntax"> = </span><span class="identifier-syntax">InterSymbol::trans</span><span class="plain-syntax">(</span><span class="identifier-syntax">A</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">A</span><span class="plain-syntax"> == </span><span class="identifier-syntax">RunningPipelines::get_symbol</span><span class="plain-syntax">(</span><span class="identifier-syntax">gen</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">from_step</span><span class="plain-syntax">, </span><span class="identifier-syntax">verb_directive_meta_RPSYM</span><span class="plain-syntax">)) </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"meta"</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">else</span><span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">A</span><span class="plain-syntax"> == </span><span class="identifier-syntax">RunningPipelines::get_symbol</span><span class="plain-syntax">(</span><span class="identifier-syntax">gen</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">from_step</span><span class="plain-syntax">, </span><span class="identifier-syntax">verb_directive_divider_RPSYM</span><span class="plain-syntax">)) </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"\n\t*"</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">else</span><span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">A</span><span class="plain-syntax"> == </span><span class="identifier-syntax">RunningPipelines::get_symbol</span><span class="plain-syntax">(</span><span class="identifier-syntax">gen</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">from_step</span><span class="plain-syntax">, </span><span class="identifier-syntax">verb_directive_reverse_RPSYM</span><span class="plain-syntax">)) </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"reverse"</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">else</span><span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">A</span><span class="plain-syntax"> == </span><span class="identifier-syntax">RunningPipelines::get_symbol</span><span class="plain-syntax">(</span><span class="identifier-syntax">gen</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">from_step</span><span class="plain-syntax">, </span><span class="identifier-syntax">verb_directive_slash_RPSYM</span><span class="plain-syntax">)) </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-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="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">A</span><span class="plain-syntax"> == </span><span class="identifier-syntax">RunningPipelines::get_symbol</span><span class="plain-syntax">(</span><span class="identifier-syntax">gen</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">from_step</span><span class="plain-syntax">, </span><span class="identifier-syntax">verb_directive_result_RPSYM</span><span class="plain-syntax">)) </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"-&gt;"</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">else</span><span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">A</span><span class="plain-syntax"> == </span><span class="identifier-syntax">RunningPipelines::get_symbol</span><span class="plain-syntax">(</span><span class="identifier-syntax">gen</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">from_step</span><span class="plain-syntax">, </span><span class="identifier-syntax">verb_directive_special_RPSYM</span><span class="plain-syntax">)) </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"special"</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">else</span><span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">A</span><span class="plain-syntax"> == </span><span class="identifier-syntax">RunningPipelines::get_symbol</span><span class="plain-syntax">(</span><span class="identifier-syntax">gen</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">from_step</span><span class="plain-syntax">, </span><span class="identifier-syntax">verb_directive_number_RPSYM</span><span class="plain-syntax">)) </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"number"</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">else</span><span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">A</span><span class="plain-syntax"> == </span><span class="identifier-syntax">RunningPipelines::get_symbol</span><span class="plain-syntax">(</span><span class="identifier-syntax">gen</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">from_step</span><span class="plain-syntax">, </span><span class="identifier-syntax">verb_directive_noun_RPSYM</span><span class="plain-syntax">)) </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"noun"</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">else</span><span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">A</span><span class="plain-syntax"> == </span><span class="identifier-syntax">RunningPipelines::get_symbol</span><span class="plain-syntax">(</span><span class="identifier-syntax">gen</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">from_step</span><span class="plain-syntax">, </span><span class="identifier-syntax">verb_directive_multi_RPSYM</span><span class="plain-syntax">)) </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"multi"</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">else</span><span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">A</span><span class="plain-syntax"> == </span><span class="identifier-syntax">RunningPipelines::get_symbol</span><span class="plain-syntax">(</span><span class="identifier-syntax">gen</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">from_step</span><span class="plain-syntax">, </span><span class="identifier-syntax">verb_directive_multiinside_RPSYM</span><span class="plain-syntax">)) </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"multiinside"</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">else</span><span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">A</span><span class="plain-syntax"> == </span><span class="identifier-syntax">RunningPipelines::get_symbol</span><span class="plain-syntax">(</span><span class="identifier-syntax">gen</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">from_step</span><span class="plain-syntax">, </span><span class="identifier-syntax">verb_directive_multiheld_RPSYM</span><span class="plain-syntax">)) </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"multiheld"</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">else</span><span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">A</span><span class="plain-syntax"> == </span><span class="identifier-syntax">RunningPipelines::get_symbol</span><span class="plain-syntax">(</span><span class="identifier-syntax">gen</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">from_step</span><span class="plain-syntax">, </span><span class="identifier-syntax">verb_directive_held_RPSYM</span><span class="plain-syntax">)) </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"held"</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">else</span><span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">A</span><span class="plain-syntax"> == </span><span class="identifier-syntax">RunningPipelines::get_symbol</span><span class="plain-syntax">(</span><span class="identifier-syntax">gen</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">from_step</span><span class="plain-syntax">, </span><span class="identifier-syntax">verb_directive_creature_RPSYM</span><span class="plain-syntax">)) </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"creature"</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">else</span><span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">A</span><span class="plain-syntax"> == </span><span class="identifier-syntax">RunningPipelines::get_symbol</span><span class="plain-syntax">(</span><span class="identifier-syntax">gen</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">from_step</span><span class="plain-syntax">, </span><span class="identifier-syntax">verb_directive_topic_RPSYM</span><span class="plain-syntax">)) </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"topic"</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">else</span><span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">A</span><span class="plain-syntax"> == </span><span class="identifier-syntax">RunningPipelines::get_symbol</span><span class="plain-syntax">(</span><span class="identifier-syntax">gen</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">from_step</span><span class="plain-syntax">, </span><span class="identifier-syntax">verb_directive_multiexcept_RPSYM</span><span class="plain-syntax">)) </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"multiexcept"</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">else</span><span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">A</span><span class="plain-syntax"> == </span><span class="identifier-syntax">RunningPipelines::get_symbol</span><span class="plain-syntax">(</span><span class="identifier-syntax">gen</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">from_step</span><span class="plain-syntax">, </span><span class="identifier-syntax">verb_directive_noun_filter_RPSYM</span><span class="plain-syntax">)) </span><span class="identifier-syntax">marker</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="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">A</span><span class="plain-syntax"> == </span><span class="identifier-syntax">RunningPipelines::get_symbol</span><span class="plain-syntax">(</span><span class="identifier-syntax">gen</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">from_step</span><span class="plain-syntax">, </span><span class="identifier-syntax">verb_directive_scope_filter_RPSYM</span><span class="plain-syntax">)) </span><span class="identifier-syntax">marker</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="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">Str::begins_with_wide_string</span><span class="plain-syntax">(</span><span class="identifier-syntax">S</span><span class="plain-syntax">, </span><span class="identifier-syntax">L</span><span class="string-syntax">"##"</span><span class="plain-syntax">)) </span><span class="named-paragraph-container code-font"><a href="4-i6c.html#SP3_1_1" class="named-paragraph-link"><span class="named-paragraph">Write without sharps</span><span class="named-paragraph-number">3.1.1</span></a></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">marker</span><span class="plain-syntax"> == </span><span class="identifier-syntax">FALSE</span><span class="plain-syntax">) </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"scope="</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">marker</span><span class="plain-syntax"> == </span><span class="identifier-syntax">TRUE</span><span class="plain-syntax">) </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"noun="</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><a href="4-i6c.html#SP9" class="function-link"><span class="function-syntax">I6TargetConstants::compile_literal_symbol</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">gtr</span><span class="plain-syntax">, </span><span class="identifier-syntax">gen</span><span class="plain-syntax">, </span><span class="identifier-syntax">A</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">marker</span><span class="plain-syntax"> = </span><span class="identifier-syntax">NOT_APPLICABLE</span><span class="plain-syntax">;</span>
<span class="plain-syntax"> }</span>
<span class="plain-syntax"> } </span><span class="reserved-syntax">else</span><span class="plain-syntax"> {</span>
<span class="plain-syntax"> </span><a href="2-cg.html#SP18" class="function-link"><span class="function-syntax">CodeGen::pair</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">gen</span><span class="plain-syntax">, </span><span class="identifier-syntax">P</span><span class="plain-syntax">, </span><span class="identifier-syntax">val</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> }</span>
<span class="plain-syntax"> }</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">";\n"</span><span class="plain-syntax">);</span>
</pre>
<ul class="endnotetexts"><li>This code is used in <a href="4-i6c.html#SP3">&#167;3</a>.</li></ul>
<p class="commentary firstcommentary"><a id="SP3_1_1" class="paragraph-anchor"></a><b>&#167;3.1.1. </b>When an action is named in a <span class="extract"><span class="extract-syntax">Verb</span></span> directive, it appears without its <span class="extract"><span class="extract-syntax">##</span></span> prefix;
so the following ensures that we write, say,
</p>
<pre class="displayed-code all-displayed-code code-font">
<span class="plain-syntax"> </span><span class="identifier-syntax">Verb</span><span class="plain-syntax"> </span><span class="character-syntax">'help'</span><span class="plain-syntax"> * -&gt; </span><span class="identifier-syntax">Help</span><span class="plain-syntax">;</span>
</pre>
<p class="commentary">rather than
</p>
<pre class="displayed-code all-displayed-code code-font">
<span class="plain-syntax"> </span><span class="identifier-syntax">Verb</span><span class="plain-syntax"> </span><span class="character-syntax">'help'</span><span class="plain-syntax"> * -&gt; ##</span><span class="identifier-syntax">Help</span><span class="plain-syntax">;</span>
</pre>
<p class="commentary">which would be a more consistent design, but is a syntax error in I6.
</p>
<p class="commentary"><span class="named-paragraph-container code-font"><span class="named-paragraph-defn">Write without sharps</span><span class="named-paragraph-number">3.1.1</span></span><span class="comment-syntax"> =</span>
</p>
<pre class="displayed-code all-displayed-code code-font">
<span class="plain-syntax"> </span><span class="identifier-syntax">LOOP_THROUGH_TEXT</span><span class="plain-syntax">(</span><span class="identifier-syntax">pos</span><span class="plain-syntax">, </span><span class="identifier-syntax">S</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">pos</span><span class="plain-syntax">.</span><span class="identifier-syntax">index</span><span class="plain-syntax"> &gt;= </span><span class="constant-syntax">2</span><span class="plain-syntax">)</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">PUT</span><span class="plain-syntax">(</span><span class="identifier-syntax">Str::get</span><span class="plain-syntax">(</span><span class="identifier-syntax">pos</span><span class="plain-syntax">));</span>
</pre>
<ul class="endnotetexts"><li>This code is used in <a href="4-i6c.html#SP3_1">&#167;3.1</a>.</li></ul>
<p class="commentary firstcommentary"><a id="SP3_2" class="paragraph-anchor"></a><b>&#167;3.2. </b>Enough of verbs. A general array is more straightforward, except for a quirk
(read: blunder) in I6 syntax. In I6,
</p>
<pre class="displayed-code all-displayed-code code-font">
<span class="plain-syntax"> </span><span class="reserved-syntax">Array</span><span class="plain-syntax"> </span><span class="identifier-syntax">X</span><span class="plain-syntax"> </span><span class="identifier-syntax">table</span><span class="plain-syntax"> </span><span class="constant-syntax">10</span><span class="plain-syntax"> </span><span class="constant-syntax">20</span><span class="plain-syntax"> </span><span class="constant-syntax">30</span><span class="plain-syntax">;</span>
</pre>
<p class="commentary">makes a table array with three entries, so that <span class="extract"><span class="extract-syntax">X</span></span> ends up as a pointer to a
block of four words in memory: <span class="extract"><span class="extract-syntax">3, 10, 20, 30</span></span>. However,
</p>
<pre class="displayed-code all-displayed-code code-font">
<span class="plain-syntax"> </span><span class="reserved-syntax">Array</span><span class="plain-syntax"> </span><span class="identifier-syntax">X</span><span class="plain-syntax"> </span><span class="identifier-syntax">table</span><span class="plain-syntax"> </span><span class="constant-syntax">10</span><span class="plain-syntax">;</span>
</pre>
<p class="commentary">makes a table with 10 entries, initially zeroes, so that <span class="extract"><span class="extract-syntax">X</span></span> points to the
block <span class="extract"><span class="extract-syntax">10, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0</span></span>. We do not want this: there are times
when we genuinely need a 1-entry table array. So we use the alternate syntax,
provided by Inform 6 since at least 2000 but for some reason not documented in
the DM4:
</p>
<pre class="displayed-code all-displayed-code code-font">
<span class="plain-syntax"> </span><span class="reserved-syntax">Array</span><span class="plain-syntax"> </span><span class="identifier-syntax">X</span><span class="plain-syntax"> </span><span class="identifier-syntax">table</span><span class="plain-syntax"> [ </span><span class="constant-syntax">10</span><span class="plain-syntax"> ];</span>
</pre>
<p class="commentary"><span class="named-paragraph-container code-font"><span class="named-paragraph-defn">Begin an I6 Array directive</span><span class="named-paragraph-number">3.2</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">saved</span><span class="plain-syntax">) *</span><span class="identifier-syntax">saved</span><span class="plain-syntax"> = </span><a href="2-cg.html#SP12" class="function-link"><span class="function-syntax">CodeGen::select</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">gen</span><span class="plain-syntax">, </span><span class="constant-syntax">arrays_I7CGS</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">OUT</span><span class="plain-syntax"> = </span><a href="2-cg.html#SP14" class="function-link"><span class="function-syntax">CodeGen::current</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">gen</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"Array %S "</span><span class="plain-syntax">, </span><span class="identifier-syntax">array_name</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">format</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">WORD_ARRAY_FORMAT:</span><span class="plain-syntax"> </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"--&gt;"</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">BYTE_ARRAY_FORMAT:</span><span class="plain-syntax"> </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"-&gt;"</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">TABLE_ARRAY_FORMAT:</span><span class="plain-syntax"> </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"table"</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">BUFFER_ARRAY_FORMAT:</span><span class="plain-syntax"> </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"buffer"</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="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">zero_count</span><span class="plain-syntax"> &gt;= </span><span class="constant-syntax">0</span><span class="plain-syntax">) {</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">" %d"</span><span class="plain-syntax">, </span><span class="identifier-syntax">zero_count</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">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">" ["</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> }</span>
</pre>
<ul class="endnotetexts"><li>This code is used in <a href="4-i6c.html#SP3">&#167;3</a>.</li></ul>
<p class="commentary firstcommentary"><a id="SP4" class="paragraph-anchor"></a><b>&#167;4. </b>A further quirk (again, blunder) is that I6 has no delimiter syntax to mark
off one entry from the next &mdash; in most languages, such as C, a comma would be
used, but I6 uses only white space.
</p>
<p class="commentary">That's fine until entries begin with operators which are ambiguously unary
or binary &mdash; in other words, with minus signs. In I6, this:
</p>
<pre class="displayed-code all-displayed-code code-font">
<span class="plain-syntax"> </span><span class="reserved-syntax">Array</span><span class="plain-syntax"> </span><span class="identifier-syntax">X</span><span class="plain-syntax"> --&gt; [ </span><span class="constant-syntax">2</span><span class="plain-syntax"> </span><span class="constant-syntax">4</span><span class="plain-syntax"> -5 ];</span>
</pre>
<p class="commentary">makes a two-element array, with <span class="extract"><span class="extract-syntax">X</span></span> pointing to <span class="extract"><span class="extract-syntax">2, -1</span></span>, because <span class="extract"><span class="extract-syntax">4 -5</span></span> is
read as a binary operation (subtraction), not as 4 followed by a unary
operation (negation) applied to 5.
</p>
<p class="commentary">We avoid this by placing semicolons after every entry, just in case:
</p>
<pre class="displayed-code all-displayed-code code-font">
<span class="plain-syntax"> </span><span class="reserved-syntax">Array</span><span class="plain-syntax"> </span><span class="identifier-syntax">X</span><span class="plain-syntax"> --&gt; [ </span><span class="constant-syntax">2</span><span class="plain-syntax">; </span><span class="constant-syntax">4</span><span class="plain-syntax">; -5; ];</span>
</pre>
<p class="commentary">Again, though undocumented in the DM4, this is a long-established syntax in I6.
</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">I6TargetConstants::array_entry</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">I6TargetConstants::array_entry</span></span>:<br/><a href="4-i6c.html#SP1">&#167;1</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">code_generator</span><span class="plain-syntax"> *</span><span class="identifier-syntax">gtr</span><span class="plain-syntax">, </span><span class="reserved-syntax">code_generation</span><span class="plain-syntax"> *</span><span class="identifier-syntax">gen</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">entry</span><span class="plain-syntax">, </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">format</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">OUT</span><span class="plain-syntax"> = </span><a href="2-cg.html#SP14" class="function-link"><span class="function-syntax">CodeGen::current</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">gen</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">" %S;"</span><span class="plain-syntax">, </span><span class="identifier-syntax">entry</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">I6TargetConstants::end_array</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">I6TargetConstants::end_array</span></span>:<br/><a href="4-i6c.html#SP1">&#167;1</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">code_generator</span><span class="plain-syntax"> *</span><span class="identifier-syntax">gtr</span><span class="plain-syntax">, </span><span class="reserved-syntax">code_generation</span><span class="plain-syntax"> *</span><span class="identifier-syntax">gen</span><span class="plain-syntax">, </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">format</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">zero_count</span><span class="plain-syntax">, </span><span class="reserved-syntax">segmentation_pos</span><span class="plain-syntax"> *</span><span class="identifier-syntax">saved</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">OUT</span><span class="plain-syntax"> = </span><a href="2-cg.html#SP14" class="function-link"><span class="function-syntax">CodeGen::current</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">gen</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">zero_count</span><span class="plain-syntax"> &lt; </span><span class="constant-syntax">0</span><span class="plain-syntax">) </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">" ];\n"</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">else</span><span class="plain-syntax"> </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"; ! blank with extent %d\n"</span><span class="plain-syntax">, </span><span class="identifier-syntax">zero_count</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">saved</span><span class="plain-syntax">) </span><a href="2-cg.html#SP12" class="function-link"><span class="function-syntax">CodeGen::deselect</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">gen</span><span class="plain-syntax">, *</span><span class="identifier-syntax">saved</span><span class="plain-syntax">);</span>
<span class="plain-syntax">}</span>
</pre>
<p class="commentary firstcommentary"><a id="SP5" class="paragraph-anchor"></a><b>&#167;5. Actions. </b>In I6, actions are implicitly created when they are used in command-grammar
syntax (i.e. in <span class="extract"><span class="extract-syntax">Verb</span></span> directives); so if <span class="extract"><span class="extract-syntax">true_action</span></span> is set, we do nothing.
</p>
<p class="commentary">Fake actions, where <span class="extract"><span class="extract-syntax">true_action</span></span> is not set, are those which are valid actions
in principle but which never occur in any command grammar. It follows that these
must be explicitly declared, which we do with the I6 <span class="extract"><span class="extract-syntax">Fake_Action</span></span> directive:
</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">I6TargetConstants::new_action</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">I6TargetConstants::new_action</span></span>:<br/><a href="4-i6c.html#SP1">&#167;1</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">code_generator</span><span class="plain-syntax"> *</span><span class="identifier-syntax">gtr</span><span class="plain-syntax">, </span><span class="reserved-syntax">code_generation</span><span class="plain-syntax"> *</span><span class="identifier-syntax">gen</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">name</span><span class="plain-syntax">, </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">true_action</span><span class="plain-syntax">, </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">N</span><span class="plain-syntax">) {</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">true_action</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">segmentation_pos</span><span class="plain-syntax"> </span><span class="identifier-syntax">saved</span><span class="plain-syntax"> = </span><a href="2-cg.html#SP12" class="function-link"><span class="function-syntax">CodeGen::select</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">gen</span><span class="plain-syntax">, </span><span class="constant-syntax">fake_actions_I7CGS</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">OUT</span><span class="plain-syntax"> = </span><a href="2-cg.html#SP14" class="function-link"><span class="function-syntax">CodeGen::current</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">gen</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"Fake_Action %S;\n"</span><span class="plain-syntax">, </span><span class="identifier-syntax">name</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><a href="2-cg.html#SP12" class="function-link"><span class="function-syntax">CodeGen::deselect</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">gen</span><span class="plain-syntax">, </span><span class="identifier-syntax">saved</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> }</span>
<span class="plain-syntax">}</span>
</pre>
<p class="commentary firstcommentary"><a id="SP6" class="paragraph-anchor"></a><b>&#167;6. Literals. </b>Integer literals are written in the obvious way. In hexadecimal, I6 uses a
single <span class="extract"><span class="extract-syntax">$</span></span> prefix. Real literals also begin with a <span class="extract"><span class="extract-syntax">$</span></span>, but then continue with
a real-number notation including a decimal point. The same notation is used
by Inter, so we need do nothing to modify it here.
</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">I6TargetConstants::compile_literal_number</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">I6TargetConstants::compile_literal_number</span></span>:<br/><a href="4-i6c.html#SP1">&#167;1</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">code_generator</span><span class="plain-syntax"> *</span><span class="identifier-syntax">gtr</span><span class="plain-syntax">,</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">code_generation</span><span class="plain-syntax"> *</span><span class="identifier-syntax">gen</span><span class="plain-syntax">, </span><span class="identifier-syntax">inter_ti</span><span class="plain-syntax"> </span><span class="identifier-syntax">val</span><span class="plain-syntax">, </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">hex_mode</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">OUT</span><span class="plain-syntax"> = </span><a href="2-cg.html#SP14" class="function-link"><span class="function-syntax">CodeGen::current</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">gen</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">hex_mode</span><span class="plain-syntax">) </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"$%x"</span><span class="plain-syntax">, </span><span class="identifier-syntax">val</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">else</span><span class="plain-syntax"> </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"%d"</span><span class="plain-syntax">, </span><span class="identifier-syntax">val</span><span class="plain-syntax">);</span>
<span class="plain-syntax">}</span>
<span class="reserved-syntax">void</span><span class="plain-syntax"> </span><span class="function-syntax">I6TargetConstants::compile_literal_real</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">I6TargetConstants::compile_literal_real</span></span>:<br/><a href="4-i6c.html#SP1">&#167;1</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">code_generator</span><span class="plain-syntax"> *</span><span class="identifier-syntax">gtr</span><span class="plain-syntax">,</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">code_generation</span><span class="plain-syntax"> *</span><span class="identifier-syntax">gen</span><span class="plain-syntax">, </span><span class="identifier-syntax">text_stream</span><span class="plain-syntax"> *</span><span class="identifier-syntax">textual</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">OUT</span><span class="plain-syntax"> = </span><a href="2-cg.html#SP14" class="function-link"><span class="function-syntax">CodeGen::current</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">gen</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::get_first_char</span><span class="plain-syntax">(</span><span class="identifier-syntax">textual</span><span class="plain-syntax">) != </span><span class="character-syntax">'-'</span><span class="plain-syntax">) &amp;&amp; (</span><span class="identifier-syntax">Str::get_first_char</span><span class="plain-syntax">(</span><span class="identifier-syntax">textual</span><span class="plain-syntax">) != </span><span class="character-syntax">'+'</span><span class="plain-syntax">))</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"$+%S"</span><span class="plain-syntax">, </span><span class="identifier-syntax">textual</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">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"$%S"</span><span class="plain-syntax">, </span><span class="identifier-syntax">textual</span><span class="plain-syntax">);</span>
<span class="plain-syntax">}</span>
</pre>
<p class="commentary firstcommentary"><a id="SP7" class="paragraph-anchor"></a><b>&#167;7. </b>Dictionary words &mdash; those used in the command parser grammar &mdash; are written in
single quotation marks and have their own peculiar syntax: see the Inform
Designer's Manual, 4th edition, for more. In particular note that we compile
a one-character dword to, say, <span class="extract"><span class="extract-syntax">'z//'</span></span> not <span class="extract"><span class="extract-syntax">'z'</span></span>: the double-slash is meaningless
there, but distinguishes this from the character constant <span class="extract"><span class="extract-syntax">'z'</span></span>, which evaluates
to the ZSCII code for lower-case Z.
</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">I6TargetConstants::compile_dictionary_word</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">I6TargetConstants::compile_dictionary_word</span></span>:<br/><a href="4-i6c.html#SP1">&#167;1</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">code_generator</span><span class="plain-syntax"> *</span><span class="identifier-syntax">gtr</span><span class="plain-syntax">, </span><span class="reserved-syntax">code_generation</span><span class="plain-syntax"> *</span><span class="identifier-syntax">gen</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">S</span><span class="plain-syntax">, </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">pluralise</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">OUT</span><span class="plain-syntax"> = </span><a href="2-cg.html#SP14" class="function-link"><span class="function-syntax">CodeGen::current</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">gen</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">n</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">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"'"</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">LOOP_THROUGH_TEXT</span><span class="plain-syntax">(</span><span class="identifier-syntax">pos</span><span class="plain-syntax">, </span><span class="identifier-syntax">S</span><span class="plain-syntax">) {</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">wchar_t</span><span class="plain-syntax"> </span><span class="identifier-syntax">c</span><span class="plain-syntax"> = </span><span class="identifier-syntax">Str::get</span><span class="plain-syntax">(</span><span class="identifier-syntax">pos</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">c</span><span class="plain-syntax"> &gt;= </span><span class="constant-syntax">0x100</span><span class="plain-syntax">) </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"@{%04x}"</span><span class="plain-syntax">, </span><span class="identifier-syntax">c</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">switch</span><span class="plain-syntax">(</span><span class="identifier-syntax">c</span><span class="plain-syntax">) {</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">case</span><span class="plain-syntax"> </span><span class="character-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">S</span><span class="plain-syntax">) == </span><span class="constant-syntax">1</span><span class="plain-syntax">) </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"@{2F}"</span><span class="plain-syntax">); </span><span class="reserved-syntax">else</span><span class="plain-syntax"> </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"/"</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="character-syntax">'\''</span><span class="plain-syntax">: </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-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="character-syntax">'^'</span><span class="plain-syntax">: </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"@{5E}"</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="character-syntax">'~'</span><span class="plain-syntax">: </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"@{7E}"</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="character-syntax">'@'</span><span class="plain-syntax">: </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"@{40}"</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">PUT</span><span class="plain-syntax">(</span><span class="identifier-syntax">c</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> }</span>
<span class="plain-syntax"> }</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">n</span><span class="plain-syntax">++ &gt; </span><span class="constant-syntax">32</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="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">pluralise</span><span class="plain-syntax">) </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"//p"</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">else</span><span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">Str::len</span><span class="plain-syntax">(</span><span class="identifier-syntax">S</span><span class="plain-syntax">) == </span><span class="constant-syntax">1</span><span class="plain-syntax">) </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"//"</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">WRITE</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="SP8" class="paragraph-anchor"></a><b>&#167;8. </b>Literal texts, written in double quotation marks, are more of a slog to get
right, and have subtly different escape-character syntax: again, see the DM4.
</p>
<p class="commentary">Note that the <span class="extract"><span class="extract-syntax">PRINTING_LTM</span></span> literal text mode is enabled when the following
is used for text appearing in an I6 <span class="extract"><span class="extract-syntax">print</span></span> statement, rather than as an I6
value.
</p>
<p class="commentary">The <span class="extract"><span class="extract-syntax">BOX_LTM</span></span> mode is used for quotation text appearing in the I6 <span class="extract"><span class="extract-syntax">box</span></span> statement.
</p>
<p class="commentary">If you think it surprising that the escape characters would need to use
different syntaxes in these three cases, I won't argue.
</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">I6TargetConstants::compile_literal_text</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">I6TargetConstants::compile_literal_text</span></span>:<br/><a href="4-i6c.html#SP1">&#167;1</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">code_generator</span><span class="plain-syntax"> *</span><span class="identifier-syntax">gtr</span><span class="plain-syntax">, </span><span class="reserved-syntax">code_generation</span><span class="plain-syntax"> *</span><span class="identifier-syntax">gen</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">S</span><span class="plain-syntax">, </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">escape_mode</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">OUT</span><span class="plain-syntax"> = </span><a href="2-cg.html#SP14" class="function-link"><span class="function-syntax">CodeGen::current</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">gen</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-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">escape_mode</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">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"%S"</span><span class="plain-syntax">, </span><span class="identifier-syntax">S</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> } </span><span class="reserved-syntax">else</span><span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">gen</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">literal_text_mode</span><span class="plain-syntax"> == </span><span class="constant-syntax">BOX_LTM</span><span class="plain-syntax">) {</span>
<span class="plain-syntax"> </span><span class="named-paragraph-container code-font"><a href="4-i6c.html#SP8_1" class="named-paragraph-link"><span class="named-paragraph">Compile literal text in box mode</span><span class="named-paragraph-number">8.1</span></a></span><span class="plain-syntax">;</span>
<span class="plain-syntax"> } </span><span class="reserved-syntax">else</span><span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">gen</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">literal_text_mode</span><span class="plain-syntax"> == </span><span class="constant-syntax">PRINTING_LTM</span><span class="plain-syntax">) {</span>
<span class="plain-syntax"> </span><span class="named-paragraph-container code-font"><a href="4-i6c.html#SP8_3" class="named-paragraph-link"><span class="named-paragraph">Compile literal text in print-statement mode</span><span class="named-paragraph-number">8.3</span></a></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="named-paragraph-container code-font"><a href="4-i6c.html#SP8_2" class="named-paragraph-link"><span class="named-paragraph">Compile literal text in value mode</span><span class="named-paragraph-number">8.2</span></a></span><span class="plain-syntax">;</span>
<span class="plain-syntax"> }</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">WRITE</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="SP8_1" class="paragraph-anchor"></a><b>&#167;8.1. </b>Box mode and value mode are the same except for their handling of newlines.
Note that the two-digit hex values in braces are the ASCII values of the
characters being written.
</p>
<p class="commentary"><span class="named-paragraph-container code-font"><span class="named-paragraph-defn">Compile literal text in box mode</span><span class="named-paragraph-number">8.1</span></span><span class="comment-syntax"> =</span>
</p>
<pre class="displayed-code all-displayed-code code-font">
<span class="plain-syntax"> </span><span class="identifier-syntax">LOOP_THROUGH_TEXT</span><span class="plain-syntax">(</span><span class="identifier-syntax">pos</span><span class="plain-syntax">, </span><span class="identifier-syntax">S</span><span class="plain-syntax">) {</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">wchar_t</span><span class="plain-syntax"> </span><span class="identifier-syntax">c</span><span class="plain-syntax"> = </span><span class="identifier-syntax">Str::get</span><span class="plain-syntax">(</span><span class="identifier-syntax">pos</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">c</span><span class="plain-syntax"> &gt;= </span><span class="constant-syntax">0x100</span><span class="plain-syntax">) </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"@{%04x}"</span><span class="plain-syntax">, </span><span class="identifier-syntax">c</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">switch</span><span class="plain-syntax">(</span><span class="identifier-syntax">c</span><span class="plain-syntax">) {</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">case</span><span class="plain-syntax"> </span><span class="character-syntax">'@'</span><span class="plain-syntax">: </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"@{40}"</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="character-syntax">'"'</span><span class="plain-syntax">: </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-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="character-syntax">'^'</span><span class="plain-syntax">: </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"@{5E}"</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="character-syntax">'~'</span><span class="plain-syntax">: </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"@{7E}"</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="character-syntax">'\\'</span><span class="plain-syntax">: </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"@{5C}"</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="character-syntax">'\t'</span><span class="plain-syntax">: </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-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="character-syntax">'\n'</span><span class="plain-syntax">: </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"\"\n\""</span><span class="plain-syntax">); </span><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">NEWLINE_IN_STRING:</span><span class="plain-syntax"> </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"\"\n\""</span><span class="plain-syntax">); </span><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">PUT</span><span class="plain-syntax">(</span><span class="identifier-syntax">c</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> }</span>
<span class="plain-syntax"> }</span>
<span class="plain-syntax"> }</span>
</pre>
<ul class="endnotetexts"><li>This code is used in <a href="4-i6c.html#SP8">&#167;8</a>.</li></ul>
<p class="commentary firstcommentary"><a id="SP8_2" class="paragraph-anchor"></a><b>&#167;8.2. </b><span class="named-paragraph-container code-font"><span class="named-paragraph-defn">Compile literal text in value mode</span><span class="named-paragraph-number">8.2</span></span><span class="comment-syntax"> =</span>
</p>
<pre class="displayed-code all-displayed-code code-font">
<span class="plain-syntax"> </span><span class="identifier-syntax">LOOP_THROUGH_TEXT</span><span class="plain-syntax">(</span><span class="identifier-syntax">pos</span><span class="plain-syntax">, </span><span class="identifier-syntax">S</span><span class="plain-syntax">) {</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">wchar_t</span><span class="plain-syntax"> </span><span class="identifier-syntax">c</span><span class="plain-syntax"> = </span><span class="identifier-syntax">Str::get</span><span class="plain-syntax">(</span><span class="identifier-syntax">pos</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">c</span><span class="plain-syntax"> &gt;= </span><span class="constant-syntax">0x100</span><span class="plain-syntax">) </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"@{%04x}"</span><span class="plain-syntax">, </span><span class="identifier-syntax">c</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">switch</span><span class="plain-syntax">(</span><span class="identifier-syntax">c</span><span class="plain-syntax">) {</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">case</span><span class="plain-syntax"> </span><span class="character-syntax">'@'</span><span class="plain-syntax">: </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"@{40}"</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="character-syntax">'"'</span><span class="plain-syntax">: </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-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="character-syntax">'^'</span><span class="plain-syntax">: </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"@{5E}"</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="character-syntax">'~'</span><span class="plain-syntax">: </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"@{7E}"</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="character-syntax">'\\'</span><span class="plain-syntax">: </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"@{5C}"</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="character-syntax">'\t'</span><span class="plain-syntax">: </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-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="character-syntax">'\n'</span><span class="plain-syntax">: </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-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">NEWLINE_IN_STRING:</span><span class="plain-syntax"> </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-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="identifier-syntax">default:</span><span class="plain-syntax"> </span><span class="identifier-syntax">PUT</span><span class="plain-syntax">(</span><span class="identifier-syntax">c</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> }</span>
<span class="plain-syntax"> }</span>
<span class="plain-syntax"> }</span>
</pre>
<ul class="endnotetexts"><li>This code is used in <a href="4-i6c.html#SP8">&#167;8</a>.</li></ul>
<p class="commentary firstcommentary"><a id="SP8_3" class="paragraph-anchor"></a><b>&#167;8.3. </b>Print mode is like value mode except that, for obscure implementation reasons
inside the I6 compiler, <span class="extract"><span class="extract-syntax">@{40}</span></span>, <span class="extract"><span class="extract-syntax">@{5E}</span></span> and <span class="extract"><span class="extract-syntax">@{7E}</span></span> cannot be used to escape
those character codes, and instead the <span class="extract"><span class="extract-syntax">@@</span></span> decimal notation has to be used
instead. But that can take a decimal value of arbitrary length and has no
brace delimiters; so we must be careful not to encode <span class="extract"><span class="extract-syntax">^1</span></span> as <span class="extract"><span class="extract-syntax">"@@941"</span></span> because
that would ask for character 941, not for character 94 and then a <span class="extract"><span class="extract-syntax">1</span></span>. Instead
we encode it as <span class="extract"><span class="extract-syntax">"@@94@{31}"</span></span>, since the ASCII code for a digit 1 is 31 in
hexadecimal.
</p>
<p class="commentary"><span class="named-paragraph-container code-font"><span class="named-paragraph-defn">Compile literal text in print-statement mode</span><span class="named-paragraph-number">8.3</span></span><span class="comment-syntax"> =</span>
</p>
<pre class="displayed-code all-displayed-code code-font">
<span class="plain-syntax"> </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">esc_char</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">LOOP_THROUGH_TEXT</span><span class="plain-syntax">(</span><span class="identifier-syntax">pos</span><span class="plain-syntax">, </span><span class="identifier-syntax">S</span><span class="plain-syntax">) {</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">wchar_t</span><span class="plain-syntax"> </span><span class="identifier-syntax">c</span><span class="plain-syntax"> = </span><span class="identifier-syntax">Str::get</span><span class="plain-syntax">(</span><span class="identifier-syntax">pos</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">c</span><span class="plain-syntax"> &gt;= </span><span class="constant-syntax">0x100</span><span class="plain-syntax">) </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"@{%04x}"</span><span class="plain-syntax">, </span><span class="identifier-syntax">c</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">switch</span><span class="plain-syntax">(</span><span class="identifier-syntax">c</span><span class="plain-syntax">) {</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">case</span><span class="plain-syntax"> </span><span class="character-syntax">'@'</span><span class="plain-syntax">: </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"@@64"</span><span class="plain-syntax">); </span><span class="identifier-syntax">esc_char</span><span class="plain-syntax"> = </span><span class="identifier-syntax">TRUE</span><span class="plain-syntax">; </span><span class="reserved-syntax">continue</span><span class="plain-syntax">;</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">case</span><span class="plain-syntax"> </span><span class="character-syntax">'"'</span><span class="plain-syntax">: </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-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="character-syntax">'^'</span><span class="plain-syntax">: </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"@@94"</span><span class="plain-syntax">); </span><span class="identifier-syntax">esc_char</span><span class="plain-syntax"> = </span><span class="identifier-syntax">TRUE</span><span class="plain-syntax">; </span><span class="reserved-syntax">continue</span><span class="plain-syntax">;</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">case</span><span class="plain-syntax"> </span><span class="character-syntax">'~'</span><span class="plain-syntax">: </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"@@126"</span><span class="plain-syntax">); </span><span class="identifier-syntax">esc_char</span><span class="plain-syntax"> = </span><span class="identifier-syntax">TRUE</span><span class="plain-syntax">; </span><span class="reserved-syntax">continue</span><span class="plain-syntax">;</span>
<span class="plain-syntax"> </span><span class="reserved-syntax">case</span><span class="plain-syntax"> </span><span class="character-syntax">'\\'</span><span class="plain-syntax">: </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"@{5C}"</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="character-syntax">'\t'</span><span class="plain-syntax">: </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-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="character-syntax">'\n'</span><span class="plain-syntax">: </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-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">NEWLINE_IN_STRING:</span><span class="plain-syntax"> </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-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="identifier-syntax">default:</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">esc_char</span><span class="plain-syntax">) </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"@{%02x}"</span><span class="plain-syntax">, </span><span class="identifier-syntax">c</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">PUT</span><span class="plain-syntax">(</span><span class="identifier-syntax">c</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> }</span>
<span class="plain-syntax"> }</span>
<span class="plain-syntax"> }</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">esc_char</span><span class="plain-syntax"> = </span><span class="identifier-syntax">FALSE</span><span class="plain-syntax">;</span>
<span class="plain-syntax"> }</span>
</pre>
<ul class="endnotetexts"><li>This code is used in <a href="4-i6c.html#SP8">&#167;8</a>.</li></ul>
<p class="commentary firstcommentary"><a id="SP9" class="paragraph-anchor"></a><b>&#167;9. </b>Finally, names of constants are compiled just as themselves:
</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">I6TargetConstants::compile_literal_symbol</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">I6TargetConstants::compile_literal_symbol</span></span>:<br/><a href="4-i6c.html#SP1">&#167;1</a>, <a href="4-i6c.html#SP3_1">&#167;3.1</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">code_generator</span><span class="plain-syntax"> *</span><span class="identifier-syntax">gtr</span><span class="plain-syntax">, </span><span class="reserved-syntax">code_generation</span><span class="plain-syntax"> *</span><span class="identifier-syntax">gen</span><span class="plain-syntax">,</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">inter_symbol</span><span class="plain-syntax"> *</span><span class="identifier-syntax">A</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">OUT</span><span class="plain-syntax"> = </span><a href="2-cg.html#SP14" class="function-link"><span class="function-syntax">CodeGen::current</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">gen</span><span class="plain-syntax">);</span>
<span class="plain-syntax"> </span><span class="identifier-syntax">WRITE</span><span class="plain-syntax">(</span><span class="string-syntax">"%S"</span><span class="plain-syntax">, </span><span class="identifier-syntax">InterSymbol::trans</span><span class="plain-syntax">(</span><span class="identifier-syntax">A</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-fi6.html">&#10094;</a></li><li class="progresschapter"><a href="P-wtmd.html">P</a></li><li class="progresschapter"><a href="1-fm.html">1</a></li><li class="progresschapter"><a href="2-cg.html">2</a></li><li class="progresschapter"><a href="3-fti.html">3</a></li><li class="progresscurrentchapter">4</li><li class="progresssection"><a href="4-fi6.html">fi6</a></li><li class="progresscurrent">i6c</li><li class="progresssection"><a href="4-i6gv.html">i6gv</a></li><li class="progresssection"><a href="4-i6o.html">i6o</a></li><li class="progresssection"><a href="4-i6c2.html">i6c2</a></li><li class="progresschapter"><a href="5-fnc.html">5</a></li><li class="progressnext"><a href="4-i6gv.html">&#10095;</a></li></ul></div>
</nav><!--End of weave-->
</main>
</body>
</html>
Reference in a new issue View git blame Copy permalink