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diff --git a/doc/groff.html.node/Character-Classes.html b/doc/groff.html.node/Character-Classes.html new file mode 100644 index 0000000..6e315dd --- /dev/null +++ b/doc/groff.html.node/Character-Classes.html @@ -0,0 +1,140 @@ +<!DOCTYPE html> +<html> +<!-- Created by GNU Texinfo 7.0.3, https://www.gnu.org/software/texinfo/ --> +<head> +<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"> +<!-- This manual documents GNU troff version 1.23.0. + +Copyright © 1994-2023 Free Software Foundation, Inc. + +Permission is granted to copy, distribute and/or modify this document +under the terms of the GNU Free Documentation License, Version 1.3 or +any later version published by the Free Software Foundation; with no +Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A +copy of the license is included in the section entitled "GNU Free +Documentation License". --> +<title>Character Classes (The GNU Troff Manual)</title> + +<meta name="description" content="Character Classes (The GNU Troff Manual)"> +<meta name="keywords" content="Character Classes (The GNU Troff Manual)"> +<meta name="resource-type" content="document"> +<meta name="distribution" content="global"> +<meta name="Generator" content="makeinfo"> +<meta name="viewport" content="width=device-width,initial-scale=1"> + +<link href="index.html" rel="start" title="Top"> +<link href="Request-Index.html" rel="index" title="Request Index"> +<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents"> +<link href="Using-Fonts.html" rel="up" title="Using Fonts"> +<link href="Special-Fonts.html" rel="next" title="Special Fonts"> +<link href="Using-Symbols.html" rel="prev" title="Using Symbols"> +<style type="text/css"> +<!-- +a.copiable-link {visibility: hidden; text-decoration: none; line-height: 0em} +div.example {margin-left: 3.2em} +span.r {font-family: initial; font-weight: normal; font-style: normal} +span:hover a.copiable-link {visibility: visible} +strong.def-name {font-family: monospace; font-weight: bold; font-size: larger} +--> +</style> + + +</head> + +<body lang="en"> +<div class="subsection-level-extent" id="Character-Classes"> +<div class="nav-panel"> +<p> +Next: <a href="Special-Fonts.html" accesskey="n" rel="next">Special Fonts</a>, Previous: <a href="Using-Symbols.html" accesskey="p" rel="prev">Using Symbols</a>, Up: <a href="Using-Fonts.html" accesskey="u" rel="up">Using Fonts</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Request-Index.html" title="Index" rel="index">Index</a>]</p> +</div> +<hr> +<h4 class="subsection" id="Character-Classes-1">5.19.5 Character Classes</h4> +<a class="index-entry-id" id="index-character-classes"></a> +<a class="index-entry-id" id="index-classes_002c-character"></a> + +<p>Classes are particularly useful for East Asian languages such as +Chinese, Japanese, and Korean, where the number of needed characters is +much larger than in European languages, and where large sets of +characters share the same properties. +</p> +<dl class="first-deffn"> +<dt class="deffn" id="index-_002eclass"><span class="category-def">Request: </span><span><strong class="def-name"><code class="t">.class</code></strong> <var class="def-var-arguments">name c1 c2 …</var><a class="copiable-link" href='#index-_002eclass'> ¶</a></span></dt> +<dd><a class="index-entry-id" id="index-class"></a> +<a class="index-entry-id" id="index-character-class-_0028class_0029"></a> +<a class="index-entry-id" id="index-defining-character-class-_0028class_0029"></a> +<a class="index-entry-id" id="index-class-of-characters-_0028class_0029"></a> +<p>Define a character class (or simply “class”) <var class="var">name</var> comprising +the characters <var class="var">c1</var>, <var class="var">c2</var>, and so on. +</p> +<p>A class thus defined can then be referred to in lieu of listing all the +characters within it. Currently, only the <code class="code">cflags</code> request can +handle references to character classes. +</p> +<p>In the request’s simplest form, each <var class="var">cn</var> is a character (or special +character). +</p> +<div class="example"> +<div class="group"><pre class="example-preformatted">.class [quotes] ' \[aq] \[dq] \[oq] \[cq] \[lq] \[rq] +</pre></div></div> + +<p>Since class and glyph names share the same name space, it is recommended +to start and end the class name with <code class="code">[</code> and <code class="code">]</code>, +respectively, to avoid collisions with existing character names defined +by GNU <code class="code">troff</code> or the user (with <code class="code">char</code> and related requests). +This practice applies the presence of <code class="code">]</code> in the class name to +prevent the use of the special character escape form +<code class="code">\[<span class="r">…</span>]</code>, thus you must use the <code class="code">\C</code> escape to access +a class with such a name. +</p> +<a class="index-entry-id" id="index-GGL-_0028groff-glyph-list_0029-1"></a> +<a class="index-entry-id" id="index-groff-glyph-list-_0028GGL_0029-1"></a> +<p>You can also use a character range notation consisting of a +start character followed by ‘<samp class="samp">-</samp>’ and then an end character. +Internally, GNU <code class="code">troff</code> converts these two symbol names to +Unicode code points (according to the <code class="code">groff</code> glyph list [GGL]), +which then give the start and end value of the range. If that fails, +the class definition is skipped. +</p> +<p>Furthermore, classes can be nested. +</p> +<div class="example"> +<div class="group"><pre class="example-preformatted">.class [prepunct] , : ; > } +.class [prepunctx] \C'[prepunct]' \[u2013]-\[u2016] +</pre></div></div> + +<p>The class ‘<samp class="samp">[prepunctx]</samp>’ thus contains the contents of the class +<code class="code">[prepunct]</code> as defined above (the set ‘<samp class="samp">, : ; > }</samp>’), and +characters in the range between <code class="code">U+2013</code> and <code class="code">U+2016</code>. +</p> +<p>If you want to include ‘<samp class="samp">-</samp>’ in a class, it must be the first +character value in the argument list, otherwise it gets misinterpreted +as part of the range syntax. +</p> +<p>It is not possible to use class names as end points of range +definitions. +</p> +<p>A typical use of the <code class="code">class</code> request is to control line-breaking +and hyphenation rules as defined by the <code class="code">cflags</code> request. For +example, to inhibit line breaks before the characters belonging to the +<code class="code">prepunctx</code> class defined in the previous example, you can write +the following. +</p> +<div class="example"> +<div class="group"><pre class="example-preformatted">.cflags 2 \C'[prepunctx]' +</pre></div></div> + +<p>See the <code class="code">cflags</code> request in <a class="ref" href="Using-Symbols.html">Using Symbols</a>, for more details. +</p></dd></dl> + + +</div> +<hr> +<div class="nav-panel"> +<p> +Next: <a href="Special-Fonts.html">Special Fonts</a>, Previous: <a href="Using-Symbols.html">Using Symbols</a>, Up: <a href="Using-Fonts.html">Using Fonts</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Request-Index.html" title="Index" rel="index">Index</a>]</p> +</div> + + + +</body> +</html> |