Perl::Critic::Policy::BuiltinFunctions::ProhibitBooleanGrep - Use
"List::MoreUtils::any" instead of "grep" in boolean
context.
This Policy is part of the core Perl::Critic distribution.
Using "grep" in boolean context is a common
idiom for checking if any elements in a list match a condition. This works
because boolean context is a subset of scalar context, and grep returns the
number of matches in scalar context. A non-zero number of matches means a
match.
But consider the case of a long array where the first element is a
match. Boolean "grep" still checks all of
the rest of the elements needlessly. Instead, a better solution is to use
the "any" function from List::MoreUtils,
which short-circuits after the first successful match to save time.
This Policy is not configurable except for the standard options.
The algorithm for detecting boolean context takes a LOT of shortcuts. There are
lots of known false negatives. But, I was conservative in writing this, so I
hope there are no false positives.
Chris Dolan <cdolan@cpan.org>
Initial development of this policy was supported by a grant from the Perl
Foundation.
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.