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diff --git a/doc/groff.html.node/Tabs-and-Fields.html b/doc/groff.html.node/Tabs-and-Fields.html new file mode 100644 index 0000000..83c156e --- /dev/null +++ b/doc/groff.html.node/Tabs-and-Fields.html @@ -0,0 +1,276 @@ +<!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>Tabs and Fields (The GNU Troff Manual)</title> + +<meta name="description" content="Tabs and Fields (The GNU Troff Manual)"> +<meta name="keywords" content="Tabs and Fields (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="GNU-troff-Reference.html" rel="up" title="GNU troff Reference"> +<link href="Character-Translations.html" rel="next" title="Character Translations"> +<link href="Manipulating-Spacing.html" rel="prev" title="Manipulating Spacing"> +<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="section-level-extent" id="Tabs-and-Fields"> +<div class="nav-panel"> +<p> +Next: <a href="Character-Translations.html" accesskey="n" rel="next">Character Translations</a>, Previous: <a href="Manipulating-Spacing.html" accesskey="p" rel="prev">Manipulating Spacing</a>, Up: <a href="GNU-troff-Reference.html" accesskey="u" rel="up">GNU <code class="code">troff</code> Reference</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> +<h3 class="section" id="Tabs-and-Fields-1">5.12 Tabs and Fields</h3> +<a class="index-entry-id" id="index-tabs_002c-and-fields"></a> +<a class="index-entry-id" id="index-fields_002c-and-tabs"></a> + +<a class="index-entry-id" id="index-tab-character-encoding"></a> +<p>A tab character (<abbr class="acronym">ISO</abbr> code point 9, <abbr class="acronym">EBCDIC</abbr> +code point 5) causes a horizontal movement to the next tab stop, if +any. +</p> +<dl class="first-deffn"> +<dt class="deffn" id="index-_005ct-1"><span class="category-def">Escape sequence: </span><span><strong class="def-name"><code class="t">\t</code><span class="r"><i class="slanted"></i></span><code class="t"></code></strong><a class="copiable-link" href='#index-_005ct-1'> ¶</a></span></dt> +<dd><a class="index-entry-id" id="index-_005ct"></a> +<a class="index-entry-id" id="index-tab-character_002c-non_002dinterpreted-_0028_005ct_0029"></a> +<a class="index-entry-id" id="index-character_002c-tab_002c-non_002dinterpreted-_0028_005ct_0029"></a> +<a class="index-entry-id" id="index-_005ct_002c-and-copy-mode"></a> +<a class="index-entry-id" id="index-copy-mode_002c-and-_005ct"></a> +<a class="index-entry-id" id="index-mode_002c-copy_002c-and-_005ct"></a> +<p>Interpolate a tab in copy mode; see <a class="ref" href="Copy-Mode.html">Copy Mode</a>. +</p></dd></dl> + +<dl class="first-deffn"> +<dt class="deffn" id="index-_002eta"><span class="category-def">Request: </span><span><strong class="def-name"><code class="t">.ta</code></strong> <var class="def-var-arguments">[[<span class="r"><i class="slanted">n1</i></span> <span class="r"><i class="slanted">n2</i></span> … <span class="r"><i class="slanted">nn</i></span> ]<code class="t">T</code> <span class="r"><i class="slanted">r1</i></span> <span class="r"><i class="slanted">r2</i></span> … <span class="r"><i class="slanted">rn</i></span>]</var><a class="copiable-link" href='#index-_002eta'> ¶</a></span></dt> +<dd><a class="index-entry-id" id="index-ta"></a> +</dd><dt class="deffnx def-cmd-deffn" id="index-_005cn_005b_002etabs_005d"><span class="category-def">Register: </span><span><strong class="def-name"><code class="t">\n[.tabs]</code></strong><a class="copiable-link" href='#index-_005cn_005b_002etabs_005d'> ¶</a></span></dt> +<dd><a class="index-entry-id" id="index-_002etabs"></a> +<p>Change tab stop positions. This request takes a series of tab +specifiers as arguments (optionally divided into two groups with the +letter ‘<samp class="samp">T</samp>’) that indicate where each tab stop is to be, overriding +any previous settings. The default scaling unit is ‘<samp class="samp">m</samp>’. Invoking +<code class="code">ta</code> without an argument removes all tab stops. +<a class="index-entry-id" id="index-default-tab-stops"></a> +<a class="index-entry-id" id="index-tab-stops_002c-default"></a> +GNU <code class="code">troff</code>’s startup value is ‘<samp class="samp">T 0.5i</samp>’<!-- /@w -->. +</p> +<p>Tab stops can be specified absolutely—as distances from the left +margin. The following example sets six tab stops, one every inch. +</p> +<div class="example"> +<div class="group"><pre class="example-preformatted">.ta 1i 2i 3i 4i 5i 6i +</pre></div></div> + +<p>Tab stops can also be specified using a leading ‘<samp class="samp">+</samp>’, which means +that the specified tab stop is set relative to the previous tab stop. +For example, the following is equivalent to the previous example. +</p> +<div class="example"> +<div class="group"><pre class="example-preformatted">.ta 1i +1i +1i +1i +1i +1i +</pre></div></div> + +<p>GNU <code class="code">troff</code> supports an extended syntax to specify repeating tab +stops. These stops appear after a ‘<samp class="samp">T</samp>’ argument. Their values are +always taken as distances relative to the previous tab stop. This is +the idiomatic way to specify tab stops at equal intervals in +<code class="code">groff</code>. The following is, yet again, the same as the previous +examples. It does more, in fact, since it defines an infinite number of +tab stops at one-inch intervals. +</p> +<div class="example"> +<div class="group"><pre class="example-preformatted">.ta T 1i +</pre></div></div> + +<p>Now we are ready to interpret the full syntax given above. The +<code class="code">ta</code> request sets tabs at positions <var class="var">n1</var>, <var class="var">n2</var>, …, +<var class="var">nn</var>, then at <var class="var">nn</var>+<var class="var">r1</var>, <var class="var">nn</var>+<var class="var">r2</var>, …, +<var class="var">nn</var>+<var class="var">rn</var>, then at <var class="var">nn</var>+<var class="var">rn</var>+<var class="var">r1</var>, +<var class="var">nn</var>+<var class="var">rn</var>+<var class="var">r2</var>, …, <var class="var">nn</var>+<var class="var">rn</var>+<var class="var">rn</var>, and so +on. +</p> +<p>For example, ‘<samp class="samp">4c +6c T 3c 5c 2c</samp>’ is equivalent to ‘<samp class="samp">4c 10c 13c +18c 20c 23c 28c 30c …</samp>’. +</p> +<p>Text written to a tab column (i.e., between two tab stops, or between a +tab stop and an output line boundary) may be aligned to the right or +left, or centered in the column. This alignment is determined by +appending ‘<samp class="samp">R</samp>’, ‘<samp class="samp">L</samp>’, or ‘<samp class="samp">C</samp>’ to the tab specifier. The +default is ‘<samp class="samp">L</samp>’. +</p> +<div class="example"> +<div class="group"><pre class="example-preformatted">.ta 1i 2iC 3iR +</pre></div></div> + +<p>The beginning of an output line is not a tab stop; the text that begins +an output line is placed according to the configured alignment and +indentation; see <a class="ref" href="Manipulating-Filling-and-Adjustment.html">Manipulating Filling and Adjustment</a> and <a class="ref" href="Line-Layout.html">Line Layout</a>. +</p> +<p>A tab stop is converted into a non-breakable horizontal movement that +cannot be adjusted. +</p> +<div class="example"> +<div class="group"><pre class="example-preformatted">.ll 2i +.ds foo a\tb\tc +.ta T 1i +\*[foo] + error→ warning: cannot break line + ⇒ a b c +</pre></div></div> + +<p>The above creates a single output line that is a bit longer than two +inches (we use a string to show exactly where the tab stops are). +Now consider the following. +</p> +<div class="example"> +<div class="group"><pre class="example-preformatted">.ll 2i +.ds bar a\tb c\td +.ta T 1i +\*[bar] + error→ warning: cannot adjust line + ⇒ a b + ⇒ c d +</pre></div></div> + +<p>GNU <code class="code">troff</code> first converts the line’s tab stops into unbreakable +horizontal movements, then breaks after ‘<samp class="samp">b</samp>’. This usually isn’t +what you want. +</p> +<p>Superfluous tab characters—those that do not correspond to a tab +stop—are ignored except for the first, which delimits the characters +belonging to the last tab stop for right-alignment or centering. +</p> +<div class="example"> +<div class="group"><pre class="example-preformatted">.ds Z foo\tbar\tbaz +.ds ZZ foo\tbar\tbazqux +.ds ZZZ foo\tbar\tbaz\tqux +.ta 2i 4iR +\*[Z] +.br +\*[ZZ] +.br +\*[ZZZ] +.br + ⇒ foo bar baz + ⇒ foo bar bazqux + ⇒ foo bar bazqux +</pre></div></div> + +<p>The first line right-aligns “baz” within the second tab stop. The +second line right-aligns “bazqux” within it. The third line +right-aligns only “baz” because of the additional tab character, which +marks the end of the text occupying the last tab stop defined. +</p> +<p>Tab stops are associated with the environment (see <a class="pxref" href="Environments.html">Environments</a>). +</p> +<a class="index-entry-id" id="index-tab-stop-settings-register-_0028_002etabs_0029"></a> +<a class="index-entry-id" id="index-_002eS-register_002c-Plan-9-alias-for-_002etabs"></a> +<a class="index-entry-id" id="index-_002etabs-register_002c-Plan-9-alias-_0028_002eS_0029"></a> +<p>The read-only register <code class="code">.tabs</code> contains a string +representation of the current tab settings suitable for use as an +argument to the <code class="code">ta</code> request.<a class="footnote" id="DOCF66" href="groff.html_fot.html#FOOT66"><sup>66</sup></a> +</p> +<div class="example"> +<div class="group"><pre class="example-preformatted">.ds tab-string \n[.tabs] +\*[tab-string] + ⇒ T120u +</pre></div></div> +</dd></dl> + +<dl class="first-deffn"> +<dt class="deffn" id="index-_002etc"><span class="category-def">Request: </span><span><strong class="def-name"><code class="t">.tc</code></strong> <var class="def-var-arguments">[<span class="r"><i class="slanted">c</i></span>]</var><a class="copiable-link" href='#index-_002etc'> ¶</a></span></dt> +<dd><a class="index-entry-id" id="index-tc"></a> +<a class="index-entry-id" id="index-tab-repetition-character-_0028tc_0029"></a> +<a class="index-entry-id" id="index-character_002c-tab-repetition-_0028tc_0029"></a> +<a class="index-entry-id" id="index-glyph_002c-tab-repetition-_0028tc_0029"></a> +<p>Set the tab repetition character to the ordinary or special character +<var class="var">c</var>; normally, no glyph is written when moving to a tab stop (and +some output devices may output space characters to achieve this motion). +A <em class="dfn">tab repetition character</em> causes the formatter to write as many +instances of <var class="var">c</var> as are necessary to occupy the interval from the +horizontal drawing position to the next tab stop. With no argument, GNU +<code class="code">troff</code> reverts to the default behavior. The tab repetition +character is associated with the environment (see <a class="pxref" href="Environments.html">Environments</a>). +Only a single character of <var class="var">c</var> is recognized; any excess is ignored. +</p></dd></dl> + +<dl class="first-deffn"> +<dt class="deffn" id="index-_002elinetabs"><span class="category-def">Request: </span><span><strong class="def-name"><code class="t">.linetabs</code></strong> <var class="def-var-arguments">n</var><a class="copiable-link" href='#index-_002elinetabs'> ¶</a></span></dt> +<dd><a class="index-entry-id" id="index-linetabs"></a> +</dd><dt class="deffnx def-cmd-deffn" id="index-_005cn_005b_002elinetabs_005d"><span class="category-def">Register: </span><span><strong class="def-name"><code class="t">\n[.linetabs]</code></strong><a class="copiable-link" href='#index-_005cn_005b_002elinetabs_005d'> ¶</a></span></dt> +<dd><a class="index-entry-id" id="index-_002elinetabs-1"></a> +<a class="index-entry-id" id="index-tab_002c-line_002dtabs-mode"></a> +<a class="index-entry-id" id="index-line_002dtabs-mode"></a> +<a class="index-entry-id" id="index-mode_002c-line_002dtabs"></a> +<p>If <var class="var">n</var> is missing or non-zero, activate <em class="dfn">line-tabs</em>; deactivate +it otherwise (the default). Active line-tabs cause GNU <code class="code">troff</code> +to compute tab distances relative to the start of the output line +instead of the input line. +</p> +<div class="example"> +<div class="group"><pre class="example-preformatted">.de Tabs +. ds x a\t\c +. ds y b\t\c +. ds z c +. ta 1i 3i +\\*x +\\*y +\\*z +.. +.Tabs +.br +.linetabs +.Tabs + ⇒ a b c + ⇒ a b c +</pre></div></div> + +<p>Line-tabs activation is associated with the environment +(see <a class="pxref" href="Environments.html">Environments</a>). The read-only register <code class="code">.linetabs</code> +interpolates 1 if line-tabs are active, and 0 otherwise. +</p></dd></dl> + + + +<ul class="mini-toc"> +<li><a href="Leaders.html" accesskey="1">Leaders</a></li> +<li><a href="Fields.html" accesskey="2">Fields</a></li> +</ul> +</div> +<hr> +<div class="nav-panel"> +<p> +Next: <a href="Character-Translations.html">Character Translations</a>, Previous: <a href="Manipulating-Spacing.html">Manipulating Spacing</a>, Up: <a href="GNU-troff-Reference.html">GNU <code class="code">troff</code> Reference</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> |