NAME

Perl::Critic::Policy::ValuesAndExpressions::ProhibitInterpolationOfLiterals - Always use single quotes for literal strings.

AFFILIATION

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

DESCRIPTION

Don't use double-quotes or qq// if your string doesn't require interpolation. This saves the interpreter a bit of work and it lets the reader know that you really did intend the string to be literal.

  print "foobar";     #not ok
  print 'foobar';     #ok
  print qq/foobar/;   #not ok
  print q/foobar/;    #ok

  print "$foobar";    #ok
  print "foobar\n";   #ok
  print qq/$foobar/;  #ok
  print qq/foobar\n/; #ok

  print qq{$foobar};  #preferred
  print qq{foobar\n}; #preferred

CONFIGURATION

The types of quoting styles to exempt from this policy can be configured via the allow option. This must be a whitespace-delimited combination of some or all of the following styles: qq{}, qq(), qq[], and qq//.

This is useful because some folks have configured their editor to apply special syntax highlighting within certain styles of quotes. For example, you can tweak vim to use SQL highlighting for everything that appears within qq{} or qq[] quotes. But if those strings are literal, Perl::Critic will complain. To prevent this, put the following in your .perlcriticrc file:

  [ValuesAndExpressions::ProhibitInterpolationOfLiterals]
  allow = qq{} qq[]

AUTHOR

Jeffrey Ryan Thalhammer <thaljef@cpan.org>

COPYRIGHT