NAME

       Perl::Critic::Policy::ValuesAndExpressions::RequireInterpolationOfMetachars - Warns that
       you might have used single quotes when you really wanted double-quotes.

AFFILIATION

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

DESCRIPTION

       This policy warns you if you use single-quotes or "q//" with a string that has unescaped
       metacharacters that may need interpolation. Its hard to know for sure if a string really
       should be interpolated without looking into the symbol table.  This policy just makes an
       educated guess by looking for metacharacters and sigils which usually indicate that the
       string should be interpolated.

   Exceptions
       •   Variable names to "use vars":

               use vars '$x';          # ok
               use vars ('$y', '$z');  # ok
               use vars qw< $a $b >;   # ok

       •   Things that look like e-mail addresses:

               print 'john@foo.com';           # ok
               $address = 'suzy.bar@baz.net';  # ok

CONFIGURATION

       The "rcs_keywords" option allows you to stop this policy from complaining about things
       that look like RCS variables, for example, in deriving values for $VERSION variables.

       For example, if you've got code like

           our ($VERSION) = (q<$Revision$> =~ m/(\d+)/mx);

       You can specify

           [ValuesAndExpressions::RequireInterpolationOfMetachars]
           rcs_keywords = Revision

       in your .perlcriticrc to provide an exemption.

NOTES

       Perl's own "warnings" pragma also warns you about this.

SEE ALSO

       Perl::Critic::Policy::ValuesAndExpressions::ProhibitInterpolationOfLiterals

AUTHOR

       Jeffrey Ryan Thalhammer <jeff@imaginative-software.com>

COPYRIGHT

       Copyright (c) 2005-2011 Imaginative Software Systems.  All 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 v5.20.2     Perl::Critic::Policy::ValuesAndExpressions::RequireInterpolationOfMetachars(3pm)