Perl::Critic::Policy::ValuesAndExpressions::RequireInterpolationOfMetachars3pm
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.
Overview
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
- •
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Variable names to
"use vars":use vars '$x'; # okuse vars ('$y', '$z'); # okuse vars qw< $a $b >; # ok
- •
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Things that look like e-mail addresses:
print '[email protected]'; # ok$address = '[email protected]'; # 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.
Releases
10 releases since Debian 5.0 (Lenny); the text changed 9 times.