vars.html

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<title>vars - Perl pragma to predeclare global variable names</title>
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<h1><a>vars - Perl pragma to predeclare global variable names</a></h1>
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<h1><a name="name">NAME</a></h1>
<p>vars - Perl pragma to predeclare global variable names (obsolete)</p>
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<h1><a name="synopsis">SYNOPSIS</a></h1>
<pre>
    <span class="keyword">use</span> <span class="variable">vars</span> <span class="string">qw($frob @mung %seen)</span><span class="operator">;</span>
</pre>
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<h1><a name="description">DESCRIPTION</a></h1>
<p>NOTE: For variables in the current package, the functionality provided
by this pragma has been superseded by <a href="../lib/Pod/perlfunc.html#item_our"><code>our</code></a> declarations, available
in Perl v5.6.0 or later.  See <a href="../lib/Pod/perlfunc.html#our">our in the perlfunc manpage</a>.</p>
<p>This will predeclare all the variables whose names are 
in the list, allowing you to use them under &quot;use strict&quot;, and
disabling any typo warnings.</p>
<p>Unlike pragmas that affect the <a href="../lib/Pod/perlvar.html#item___h"><code>$^H</code></a> hints variable, the <code>use vars</code> and
<code>use subs</code> declarations are not BLOCK-scoped.  They are thus effective
for the entire file in which they appear.  You may not rescind such
declarations with <code>no vars</code> or <code>no subs</code>.</p>
<p>Packages such as the <strong>AutoLoader</strong> and <strong>SelfLoader</strong> that delay
loading of subroutines within packages can create problems with
package lexicals defined using <a href="../lib/Pod/perlfunc.html#item_my"><code>my()</code></a>. While the <strong>vars</strong> pragma
cannot duplicate the effect of package lexicals (total transparency
outside of the package), it can act as an acceptable substitute by
pre-declaring global symbols, ensuring their availability to the
later-loaded routines.</p>
<p>See <a href="../lib/Pod/perlmodlib.html#pragmatic_modules">Pragmatic Modules in the perlmodlib manpage</a>.</p>

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