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Perl::CrPerl::Critic::UsercContributedxPerlsDocumentationExtendedFormatting(3)

NAME
       Perl::Critic::Policy::RegularExpressions::RequireExtendedFormatting -
       Always use the "/x" modifier with regular expressions.

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

DESCRIPTION
       Extended	regular	expression formatting allows you mix whitespace	and
       comments	into the pattern, thus making them much	more readable.

	   # Match a single-quoted string efficiently...

	   m{'[^\\']*(?:\\.[^\\']*)*'};	 #Huh?

	   # Same thing	with extended format...

	   m{
	       '	   # an	opening	single quote
	       [^\\']	   # any non-special chars (i.e. not backslash or single quote)
	       (?:	   # then all of...
		   \\ .	   #	any explicitly backslashed char
		   [^\\']* #	followed by an non-special chars
	       )*	   # ...repeated zero or more times
	       '	   # a closing single quote
	   }x;

CONFIGURATION
       You might find that putting a "/x" on short regular expressions to be
       excessive.  An exception	can be made for	them by	setting
       "minimum_regex_length_to_complain_about"	to the minimum match length
       you'll allow without a "/x".  The length	only counts the	regular
       expression, not the braces or operators.

	   [RegularExpressions::RequireExtendedFormatting]
	   minimum_regex_length_to_complain_about = 5

	   $num	=~ m<(\d+)>;		  # ok,	only 5 characters
	   $num	=~ m<\d\.(\d+)>;	  # not	ok, 9 characters

       This option defaults to 0.

       Because using "/x" on a regex which has whitespace in it	can make it
       harder to read (you have	to escape all that innocent whitespace), by
       default,	you can	have a regular expression that only contains
       whitespace and word characters without the modifier.  If	you want to
       restrict	this, turn on the "strict" option.

	   [RegularExpressions::RequireExtendedFormatting]
	   strict = 1

	   $string =~ m/Basset hounds got long ears/;  # no longer ok

       This option defaults to false.

NOTES
       For common regular expressions like e-mail addresses, phone numbers,
       dates, etc., have a look	at the Regexp::Common module.  Also, be
       cautions	about slapping modifier	flags onto existing regular
       expressions, as they can	drastically alter their	meaning.  See
       <http://www.perlmonks.org/?node_id=484238> for an interesting
       discussion on the effects of blindly modifying regular expression
       flags.

TO DO
       Add an exemption	for regular expressions	that contain "\Q" at the front
       and don't use "\E" until	the very end, if at all.

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.Perl::Critic::Policy::RegularExpressions::RequireExtendedFormatting(3)

NAME | AFFILIATION | DESCRIPTION | CONFIGURATION | NOTES | TO DO | AUTHOR | COPYRIGHT

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