Perl::Critic::Policy::Variables::RequireLocalizedPunctuationVars(3pm)
                                           User Contributed Perl Documentation


NAME
       Perl::Critic::Policy::Variables::RequireLocalizedPunctuationVars -
       Magic variables should be assigned as "local".

AFFILIATION
       This Policy is part of the core Perl::Critic distribution.

DESCRIPTION
       Punctuation variables (and their English.pm equivalents) are global
       variables.  Messing with globals is dangerous in a complex program as
       it can lead to very subtle and hard to fix bugs.  If you must change a
       magic variable in a non-trivial program, do it in a local scope.

       For example, to slurp a filehandle into a scalar, it's common to set
       the record separator to undef instead of a newline.  If you choose to
       do this (instead of using Path::Tiny!) then be sure to localize the
       global and change it for as short a time as possible.

           # BAD:
           $/ = undef;
           my $content = <$fh>;

           # BETTER:
           my $content;
           {
               local $/ = undef;
               $content = <$fh>;
           }

           # A popular idiom:
           my $content = do { local $/ = undef; <$fh> };

       This policy also allows the use of "my".  Perl prevents using "my" with
       "proper" punctuation variables, but allows $a, @ARGV, the names
       declared by English, etc.  This is not a good coding practice, however
       it is not the concern of this specific policy to complain about that.

       There are exemptions for $_ and @_, and the English equivalent $ARG.

CONFIGURATION
       You can configure your own exemptions using the "allow" option:

           [Variables::RequireLocalizedPunctuationVars]
           allow = @ARGV $ARGV

       These are added to the default exemptions.

CREDITS
       Initial development of this policy was supported by a grant from the
       Perl Foundation.

AUTHOR
       Chris Dolan <cdolan@cpan.org>

COPYRIGHT
       Copyright (c) 2007-2011 Chris Dolan.  Many rights reserved.

       This program is free software; you can redistribute it and/or modify it
       under the same terms as Perl itself.  The full text of this license can
       be found in the LICENSE file included with this module.

perl v5.38.0                      2023-07-26
         Perl::Critic::Policy::Variables::RequireLocalizedPunctuationVars(3pm)