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Perl::Critic::Policy::BuiltinFunctions::ProhibitBooleanGrep

NAME

Perl::Critic::Policy::BuiltinFunctions::ProhibitBooleanGrep − Use "List::MoreUtils::any" instead of "grep" in boolean context.

AFFILIATION

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

DESCRIPTION

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.

CONFIGURATION

This Policy is not configurable except for the standard options.

CAVEATS

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.

AUTHOR

Chris Dolan <cdolan AT cpan DOT org>

CREDITS

Initial development of this policy was supported by a grant from the Perl Foundation.

COPYRIGHT

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.

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