ad4f267b7a
search.cpan.org is shutting down. It will redirect to metacpan.org after June 25, 2018. With hat: perl
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989 B
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19 lines
989 B
Text
Starting with Perl 5.10, it is possible to create a lexical version of the Perl
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default variable $_. Certain Perl constructs like the given keyword
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automatically use a lexical $_ rather than the global $_.
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It is occasionallly useful for a sub to be able to access its caller's $_
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variable regardless of whether it was lexical or not. The (_) sub prototype is
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the official way to do so, however there are sometimes disadvantages to this; in
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particular it can only appear as the final required argument in a prototype, and
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there is no way of the sub differentiating between an explicitly passed argument
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and $_.
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The lexical::underscore function returns a scalar reference to either a lexical
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$_ variable somewhere up the call stack (using PadWalker magic), or to the
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global $_ if there was no lexical version.
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Wrapping lexical::underscore in ${ ... } dereferences the scalar reference,
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allowing you to access (and even assign to) it.
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WWW: https://metacpan.org/release/lexical-underscore
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