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diff --git a/doc/groff.html.node/if_002delse.html b/doc/groff.html.node/if_002delse.html new file mode 100644 index 0000000..3c67fa9 --- /dev/null +++ b/doc/groff.html.node/if_002delse.html @@ -0,0 +1,97 @@ +<!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>if-else (The GNU Troff Manual)</title> + +<meta name="description" content="if-else (The GNU Troff Manual)"> +<meta name="keywords" content="if-else (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="Conditionals-and-Loops.html" rel="up" title="Conditionals and Loops"> +<link href="while.html" rel="next" title="while"> +<link href="Operators-in-Conditionals.html" rel="prev" title="Operators in Conditionals"> +<style type="text/css"> +<!-- +a.copiable-link {visibility: hidden; text-decoration: none; line-height: 0em} +div.example {margin-left: 3.2em} +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="if_002delse"> +<div class="nav-panel"> +<p> +Next: <a href="while.html" accesskey="n" rel="next">while</a>, Previous: <a href="Operators-in-Conditionals.html" accesskey="p" rel="prev">Operators in Conditionals</a>, Up: <a href="Conditionals-and-Loops.html" accesskey="u" rel="up">Conditionals and Loops</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="if_002delse-1">5.23.3 if-else</h4> +<a class="index-entry-id" id="index-if_002delse"></a> + +<dl class="first-deffn"> +<dt class="deffn" id="index-_002eie"><span class="category-def">Request: </span><span><strong class="def-name"><code class="t">.ie</code></strong> <var class="def-var-arguments">cond-expr anything</var><a class="copiable-link" href='#index-_002eie'> ¶</a></span></dt> +<dd><a class="index-entry-id" id="index-ie"></a> +</dd><dt class="deffnx def-cmd-deffn" id="index-_002eel"><span class="category-def">Request: </span><span><strong class="def-name"><code class="t">.el</code></strong> <var class="def-var-arguments">anything</var><a class="copiable-link" href='#index-_002eel'> ¶</a></span></dt> +<dd><a class="index-entry-id" id="index-el"></a> +<p>Use the <code class="code">ie</code> and <code class="code">el</code> requests to write an if-then-else. The +first request is the “if” part and the latter is the “else” part. +Unusually among programming languages, any number of non-conditional +requests may be interposed between the <code class="code">ie</code> branch and the +<code class="code">el</code> branch. +</p> +<div class="example"> +<div class="group"><pre class="example-preformatted">.nr a 0 +.ie \na a is non-zero. +.nr a +1 +.el a was not positive but is now \na. + ⇒ a was not positive but is now 1. +</pre></div></div> + +<p>Another way in which <code class="code">el</code> is an ordinary request is that it does +not lexically “bind” more tightly to its <code class="code">ie</code> counterpart than it +does to any other request. This fact can surprise C programmers. +</p> +<div class="example"> +<div class="group"><pre class="example-preformatted">.nr a 1 +.nr z 0 +.ie \nz \ +. ie \na a is true +. el a is false +.el z is false + error→ warning: unbalanced 'el' request + ⇒ a is false +</pre></div></div> + +<p>To conveniently nest conditionals, keep reading. +</p> +</dd></dl> + + +</div> + + + +</body> +</html> |