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    <p>The dollar sign here is a sigil that indicates that the named variable is a scalar.</p> <p>If there is no preceding <code>package</code> declaration, the use of <code>$var_name</code> contains an implied namespace of <code>main</code>, i.e. it is short for <code>$main::var_name</code>. In the case of your example, where you have <code>package main;</code> first, you need to stipulate that the namespace is <code>test</code>, rather than <code>main</code>, so <code>$test::testVar</code> is required.</p> <p>For a function call, you do not need to use a sigil. If you did, you would use the ampersand (<code>&amp;</code>), but using ampersands when calling functions has fallen out of favour with many programmers.*</p> <p>As before, <code>sub_name()</code> is a shortened version of <code>main::sub_name()</code>... in the same way, no sigil is needed to call <code>package::sub()</code>.</p> <p>*References as to the use of <code>&amp;</code>:</p> <ul> <li><a href="http://www.perlmonks.org/?node_id=428024" rel="nofollow">Perl Monks discussion</a></li> <li><a href="http://kobesearch.cpan.org/htdocs/Perl-Critic/Perl/Critic/Policy/Subroutines/ProhibitAmpersandSigils.pm.html" rel="nofollow">Perl::Critic</a> dislikes it, following on from <a href="http://oreilly.com/catalog/9780596001735" rel="nofollow">Perl Best Practices</a></li> <li>Per <a href="http://perldoc.perl.org/perlsub.html" rel="nofollow">perldoc</a>, using <code>&amp;</code> with a function name allows you to deviate from the <strong>usual</strong> behaviour. This can result in subtle bugs.</li> </ul>
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    1. COAmpersands are not deprecated in any way, shape or form. Some people just dislike them and they are often unnecessary, and using & without also using () creates a special kind of sub call that isn't usually intended. That last bit is sometimes used as an argument against using & in general, but I don't find it compelling.
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    2. CO@ysth fair comment. I've reworded and added some links to expand on that bit.
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    3. COI sort of, understand. I thought you were going to say, in the case of the module, the script isn't in the same main:: symbol table. I am very new to Perl to be honest and it's given me some issues.
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      1. USMike Thornley
 

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