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 <h3 class="section" id="g_t_0040alias-new_003dexisting">16.4 &lsquo;<samp class="samp">@alias <var class="var">new</var>=<var class="var">existing</var></samp>&rsquo;</h3>

 <a class="anchor" id="alias"></a><a class="index-entry-id" id="index-Aliases_002c-command"></a>
 <a class="index-entry-id" id="index-Command-aliases"></a>
 <a class="index-entry-id" id="index-alias"></a>

 <p>The &lsquo;<samp class="samp">@alias</samp>&rsquo; command defines a new command to be just like an
 existing one.  This is useful for defining additional markup names,
 thus preserving additional semantic information in the input even
 though the output result may be the same.
 </p>
 <p>Write the &lsquo;<samp class="samp">@alias</samp>&rsquo; command on a line by itself, followed by the
 new command name, an equals sign, and the existing command name.
 Whitespace around the equals sign is optional and ignored if present.
 Thus:
 </p>
 <div class="example">
 <pre class="example-preformatted">@alias <var class="var">new</var> = <var class="var">existing</var>
 </pre></div>

 <p>For example, if your document contains citations for both books and
 some other media (movies, for example), you might like to define a
 macro <code class="code">@moviecite{}</code> that does the same thing as an ordinary
 <code class="code">@cite{}</code> but conveys the extra semantic information as well.
 You&rsquo;d do this as follows:
 </p>
 <div class="example">
 <pre class="example-preformatted">@alias moviecite = cite
 </pre></div>

 <p>Macros do not always have the same effect as aliases, due to vagaries
 of argument parsing.  Also, aliases are much simpler to define than
 macros.  So the command is not redundant.
 </p>
 <p>Unfortunately, it&rsquo;s not possible to alias Texinfo environments; for
 example, <code class="code">@alias lang=example</code> is an error.
 </p>
 <p>Aliases must not be recursive, directly or indirectly.
 </p>
 <p>It is not advisable to redefine any TeX primitive, plain TeX, or
 Texinfo command name as an alias.  Unfortunately this is a very large
 set of names, and the possible resulting errors from TeX are
 unpredictable.
 </p>
 <p><code class="command">makeinfo</code> will accept the same identifiers for aliases as it
 does for macro names, that is, alphanumerics and (except as the first
 character) &lsquo;<samp class="samp">-</samp>&rsquo;.
 </p>

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 <p>
 Next: <a href="_0040definfoenclose.html"><code class="code">@definfoenclose</code>: Customized Highlighting</a>, Previous: <a href="Macro-Details.html">Macro Details and Caveats</a>, Up: <a href="Defining-New-Texinfo-Commands.html">Defining New Texinfo Commands</a> &nbsp; [<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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	Permission is granted to copy, distribute and/or modify this document
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	<p>
	Next: <a href="_0040definfoenclose.html" accesskey="n" rel="next"><code class="code">@definfoenclose</code>: Customized Highlighting</a>, Previous: <a href="Macro-Details.html" accesskey="p" rel="prev">Macro Details and Caveats</a>, Up: <a href="Defining-New-Texinfo-Commands.html" accesskey="u" rel="up">Defining New Texinfo Commands</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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	<hr>
	<h3 class="section" id="g_t_0040alias-new_003dexisting">16.4 ‘<samp class="samp">@alias <var class="var">new</var>=<var class="var">existing</var></samp>’</h3>

	<a class="anchor" id="alias"></a><a class="index-entry-id" id="index-Aliases_002c-command"></a>
	<a class="index-entry-id" id="index-Command-aliases"></a>
	<a class="index-entry-id" id="index-alias"></a>

	<p>The ‘<samp class="samp">@alias</samp>’ command defines a new command to be just like an
	existing one. This is useful for defining additional markup names,
	thus preserving additional semantic information in the input even
	though the output result may be the same.
	</p>
	<p>Write the ‘<samp class="samp">@alias</samp>’ command on a line by itself, followed by the
	new command name, an equals sign, and the existing command name.
	Whitespace around the equals sign is optional and ignored if present.
	Thus:
	</p>
	<div class="example">
	<pre class="example-preformatted">@alias <var class="var">new</var> = <var class="var">existing</var>
	</pre></div>

	<p>For example, if your document contains citations for both books and
	some other media (movies, for example), you might like to define a
	macro <code class="code">@moviecite{}</code> that does the same thing as an ordinary
	<code class="code">@cite{}</code> but conveys the extra semantic information as well.
	You’d do this as follows:
	</p>
	<div class="example">
	<pre class="example-preformatted">@alias moviecite = cite
	</pre></div>

	<p>Macros do not always have the same effect as aliases, due to vagaries
	of argument parsing. Also, aliases are much simpler to define than
	macros. So the command is not redundant.
	</p>
	<p>Unfortunately, it’s not possible to alias Texinfo environments; for
	example, <code class="code">@alias lang=example</code> is an error.
	</p>
	<p>Aliases must not be recursive, directly or indirectly.
	</p>
	<p>It is not advisable to redefine any TeX primitive, plain TeX, or
	Texinfo command name as an alias. Unfortunately this is a very large
	set of names, and the possible resulting errors from TeX are
	unpredictable.
	</p>
	<p><code class="command">makeinfo</code> will accept the same identifiers for aliases as it
	does for macro names, that is, alphanumerics and (except as the first
	character) ‘<samp class="samp">-</samp>’.
	</p>

	</div>
	<hr>
	<div class="nav-panel">
	<p>
	Next: <a href="_0040definfoenclose.html"><code class="code">@definfoenclose</code>: Customized Highlighting</a>, Previous: <a href="Macro-Details.html">Macro Details and Caveats</a>, Up: <a href="Defining-New-Texinfo-Commands.html">Defining New Texinfo Commands</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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