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diff --git a/doc/groff.html.node/Assigning-Register-Formats.html b/doc/groff.html.node/Assigning-Register-Formats.html new file mode 100644 index 0000000..ff0ddfa --- /dev/null +++ b/doc/groff.html.node/Assigning-Register-Formats.html @@ -0,0 +1,188 @@ +<!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>Assigning Register Formats (The GNU Troff Manual)</title> + +<meta name="description" content="Assigning Register Formats (The GNU Troff Manual)"> +<meta name="keywords" content="Assigning Register Formats (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="Registers.html" rel="up" title="Registers"> +<link href="Built_002din-Registers.html" rel="next" title="Built-in Registers"> +<link href="Auto_002dincrement.html" rel="prev" title="Auto-increment"> +<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="Assigning-Register-Formats"> +<div class="nav-panel"> +<p> +Next: <a href="Built_002din-Registers.html" accesskey="n" rel="next">Built-in Registers</a>, Previous: <a href="Auto_002dincrement.html" accesskey="p" rel="prev">Auto-increment</a>, Up: <a href="Registers.html" accesskey="u" rel="up">Registers</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="Assigning-Register-Formats-1">5.8.4 Assigning Register Formats</h4> +<a class="index-entry-id" id="index-assign-number-format-to-register-_0028af_0029"></a> +<a class="index-entry-id" id="index-number-formats_002c-assigning-to-register-_0028af_0029"></a> +<a class="index-entry-id" id="index-register_002c-assigning-number-format-to-_0028af_0029"></a> + +<p>A writable register’s value can be interpolated in several number +formats. By default, conventional Arabic numerals are used. +Other formats see use in sectioning and outlining schemes and +alternative page numbering arrangements. +</p> +<dl class="first-deffn"> +<dt class="deffn" id="index-_002eaf"><span class="category-def">Request: </span><span><strong class="def-name"><code class="t">.af</code></strong> <var class="def-var-arguments">reg fmt</var><a class="copiable-link" href='#index-_002eaf'> ¶</a></span></dt> +<dd><a class="index-entry-id" id="index-af"></a> +<p>Use number format <var class="var">fmt</var> when interpolating register <var class="var">reg</var>. +Valid number formats are as follows. +</p> +<dl class="table"> +<dt><code class="code">0<span class="r">…</span></code></dt> +<dd><p>Arabic numerals 0, 1, 2, and so on. +Any decimal digit is equivalent to ‘<samp class="samp">0</samp>’; the formatter merely counts +the digits specified. Multiple Arabic numerals in <var class="var">fmt</var> cause +interpolations to be zero-padded on the left if necessary to at least as +many digits as specified (interpolations never truncate a register +value). A register with format ‘<samp class="samp">00</samp>’ interpolates values 1, 2, 3 as +‘<samp class="samp">01</samp>’, ‘<samp class="samp">02</samp>’, ‘<samp class="samp">03</samp>’. The default format for all writable +registers is ‘<samp class="samp">0</samp>’. +</p> +</dd> +<dt id='index-Roman-numerals'><span><code class="code">I</code><a class="copiable-link" href='#index-Roman-numerals'> ¶</a></span></dt> +<dd><a class="index-entry-id" id="index-numerals_002c-Roman"></a> +<p>Uppercase Roman numerals: 0, I, II, III, IV, <small class="enddots">...</small> +</p> +</dd> +<dt><code class="code">i</code></dt> +<dd><p>Lowercase Roman numerals: 0, i, ii, iii, iv, <small class="enddots">...</small> +</p> +</dd> +<dt><code class="code">A</code></dt> +<dd><p>Uppercase letters: 0, A, B, C, …, Z, AA, AB, <small class="enddots">...</small> +</p> +</dd> +<dt><code class="code">a</code></dt> +<dd><p>Lowercase letters: 0, a, b, c, …, z, aa, ab, <small class="enddots">...</small> +</p></dd> +</dl> + +<p>Omitting <var class="var">fmt</var> causes a warning in category ‘<samp class="samp">missing</samp>’. +See <a class="xref" href="Warnings.html">Warnings</a>, for information about the enablement and suppression of +warnings. Specifying an unrecognized format is an error. +</p> +<p>Zero values are interpolated as ‘<samp class="samp">0</samp>’ in non-Arabic formats. +Negative quantities are prefixed with ‘<samp class="samp">-</samp>’ irrespective of format. +In Arabic formats, the sign supplements the field width. If <var class="var">reg</var> +doesn’t exist, it is created with a zero value. +</p> +<div class="example"> +<div class="group"><pre class="example-preformatted">.nr a 10 +.af a 0 \" the default format +\na, +.af a I +\na, +.af a 321 +.nr a (-\na) +\na, +.af a a +\na + ⇒ 10, X, -010, -j +</pre></div></div> + +<a class="index-entry-id" id="index-Roman-numerals_002c-extrema-_0028maximum-and-minimum_0029"></a> +<a class="index-entry-id" id="index-extreme-values-representable-with-Roman-numerals"></a> +<a class="index-entry-id" id="index-maximum-value-representable-with-Roman-numerals"></a> +<a class="index-entry-id" id="index-minimum-value-representable-with-Roman-numerals"></a> +<p>The representable extrema in the ‘<samp class="samp">i</samp>’ and ‘<samp class="samp">I</samp>’ formats +correspond to Arabic ±39,999. GNU <code class="code">troff</code> uses ‘<samp class="samp">w</samp>’ and +‘<samp class="samp">z</samp>’ to represent 5,000 and 10,000 in Roman numerals, respectively, +following the convention of <abbr class="acronym">AT&T</abbr> <code class="code">troff</code>—currently, the +correct glyphs for Roman numerals five thousand (<code class="code">U+2181</code>) and ten +thousand (<code class="code">U+2182</code>) are not used. +</p> +<a class="index-entry-id" id="index-read_002donly-register_002c-changing-format"></a> +<a class="index-entry-id" id="index-changing-format_002c-and-read_002donly-registers"></a> +<p>Assigning the format of a read-only register is an error. Instead, copy +the read-only register’s value to, and assign the format of, a writable +register. +</p></dd></dl> + +<dl class="first-deffn"> +<dt class="deffn" id="index-_005cgr"><span class="category-def">Escape sequence: </span><span><strong class="def-name"><code class="t">\g</code><span class="r"><i class="slanted">r</i></span><code class="t"></code></strong><a class="copiable-link" href='#index-_005cgr'> ¶</a></span></dt> +<dd><a class="index-entry-id" id="index-_005cg"></a> +</dd><dt class="deffnx def-cmd-deffn" id="index-_005cg_0028rg"><span class="category-def">Escape sequence: </span><span><strong class="def-name"><code class="t">\g(</code><span class="r"><i class="slanted">rg</i></span><code class="t"></code></strong><a class="copiable-link" href='#index-_005cg_0028rg'> ¶</a></span></dt> +<dt class="deffnx def-cmd-deffn" id="index-_005cg_005breg_005d"><span class="category-def">Escape sequence: </span><span><strong class="def-name"><code class="t">\g[</code><span class="r"><i class="slanted">reg</i></span><code class="t">]</code></strong><a class="copiable-link" href='#index-_005cg_005breg_005d'> ¶</a></span></dt> +<dd><a class="index-entry-id" id="index-format-of-register-_0028_005cg_0029"></a> +<a class="index-entry-id" id="index-register_002c-format-_0028_005cg_0029"></a> +<p>Interpolate the format of the register <var class="var">reg</var> (one-character +name <var class="var">r</var>, two-character name <var class="var">rg</var>). Zeroes represent +Arabic formats. If <var class="var">reg</var> is not defined, <var class="var">reg</var> is not created +and nothing is interpolated. <code class="code">\g</code> is interpreted even in copy mode +(see <a class="pxref" href="Copy-Mode.html">Copy Mode</a>). +</p></dd></dl> + +<a class="index-entry-id" id="index-register-format_002c-in-expressions"></a> +<a class="index-entry-id" id="index-expressions_002c-and-register-format"></a> +<p>GNU <code class="code">troff</code> interprets only Arabic numerals. The Roman numeral or +alphabetic formats cannot be used as operands to arithmetic operators in +expressions (see <a class="pxref" href="Numeric-Expressions.html">Numeric Expressions</a>). For instance, it may be +desirable to test the page number independently of its format. +</p> +<div class="example"> +<div class="group"><pre class="example-preformatted">.af % i \" front matter +.de header-trap +. \" To test the page number, we need it in Arabic. +. ds saved-page-number-format \\g%\" +. af % 0 +. nr page-number-in-decimal \\n% +. af % \\*[saved-page-number-format] +. ie \\n[page-number-in-decimal]=1 .do-first-page-stuff +. el \{\ +. ie o .do-odd-numbered-page-stuff +. el .do-even-numbered-page-stuff +. \} +. rm saved-page-number-format +.. +.wh 0 header-trap +</pre></div></div> + + +</div> +<hr> +<div class="nav-panel"> +<p> +Next: <a href="Built_002din-Registers.html">Built-in Registers</a>, Previous: <a href="Auto_002dincrement.html">Auto-increment</a>, Up: <a href="Registers.html">Registers</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> |