Perl::Critic::Policy::RegularExpressions::ProhibitSingleCharAlternation - Use
"[abc]" instead of "a|b|c".
This Policy is part of the core Perl::Critic distribution.
Character classes (like "[abc]") are
significantly faster than single character alternations (like
"(?:a|b|c)"). This policy complains if you
have more than one instance of a single character in an alternation. So
"(?:a|the)" is allowed, but
"(?:a|e|i|o|u)" is not.
NOTE: Perl 5.10 (not released as of this writing) has major regexp
optimizations which may mitigate the performance penalty of alternations,
which will be rewritten behind the scenes as something like character
classes. Consequently, if you are deploying exclusively on 5.10, yo might
consider ignoring this policy.
This Policy is not configurable except for the standard options.
Initial development of this policy was supported by a grant from the Perl
Foundation.
Chris Dolan <cdolan@cpan.org>
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