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<span id="g_t_0040ifset-_0040ifclear"></span><div class="header">
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<hr>
<span id="g_t_0040ifset-and-_0040ifclear"></span><h4 class="subsection">16.5.2 <code>@ifset</code> and <code>@ifclear</code></h4>
<span id="ifset-ifclear"></span><span id="index-ifset"></span>
<p>When a <var>flag</var> is set, the Texinfo formatting commands format text
between subsequent pairs of <code>@ifset <var>flag</var></code> and <code>@end
ifset</code> commands. When the <var>flag</var> is cleared, the Texinfo formatting
commands do <em>not</em> format the text. <code>@ifclear</code> operates
analogously.
</p>
<p>Write the conditionally formatted text between <code>@ifset <var>flag</var></code>
and <code>@end ifset</code> commands, like this:
</p>
<div class="example">
<pre class="example">@ifset <var>flag</var>
<var>conditional-text</var>
@end ifset
</pre></div>
<p>For example, you can create one document that has two variants, such as
a manual for a ‘large’ and ‘small’ model:
</p>
<span id="index-Shrubbery"></span>
<div class="example">
<pre class="example">You can use this machine to dig up shrubs
without hurting them.
@set large
@ifset large
It can also dig up fully grown trees.
@end ifset
Remember to replant promptly …
</pre></div>
<p>In the example, the formatting commands will format the text between
<code>@ifset large</code> and <code>@end ifset</code> because the <code>large</code>
flag is set.
</p>
<p>When <var>flag</var> is cleared, the Texinfo formatting commands do
<em>not</em> format the text between <code>@ifset <var>flag</var></code> and
<code>@end ifset</code>; that text is ignored and does not appear in either
printed or Info output.
</p>
<p>For example, if you clear the flag of the preceding example by writing
an <code>@clear large</code> command after the <code>@set large</code> command
(but before the conditional text), then the Texinfo formatting commands
ignore the text between the <code>@ifset large</code> and <code>@end ifset</code>
commands. In the formatted output, that text does not appear; in both
printed and Info output, you see only the lines that say, “You can use
this machine to dig up shrubs without hurting them. Remember to replant
promptly …”.
</p>
<span id="index-ifclear"></span>
<p>If a flag is cleared with a <code>@clear <var>flag</var></code> command, then
the formatting commands format text between subsequent pairs of
<code>@ifclear</code> and <code>@end ifclear</code> commands. But if the flag
is set with <code>@set <var>flag</var></code>, then the formatting commands do
<em>not</em> format text between an <code>@ifclear</code> and an <code>@end
ifclear</code> command; rather, they ignore that text. An <code>@ifclear</code>
command looks like this:
</p>
<div class="example">
<pre class="example">@ifclear <var>flag</var>
</pre></div>
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Next: <a href="_0040inlineifset-_0040inlineifclear.html" accesskey="n" rel="next"><code>@inlineifset @inlineifclear</code></a>, Previous: <a href="_0040set-_0040value.html" accesskey="p" rel="prev"><code>@set @value</code></a>, Up: <a href="_0040set-_0040clear-_0040value.html" accesskey="u" rel="up"><code>@set @clear @value</code></a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Command-and-Variable-Index.html" title="Index" rel="index">Index</a>]</p>
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