Perl::Critic::Policy::ControlStructures::ProhibitNegativeExpressionsInUnlessAndUntilConditions - Don't use operators like not, !~, and le within until and unless.
not
!~
le
until
unless
This Policy is part of the core Perl::Critic distribution.
until ($foo ne 'blah') { #not ok ... } while ($foo eq 'blah') { #ok ... }
A number of people have problems figuring out the meaning of doubly negated expressions. unless and until are both negative constructs, so any negative (e.g. !~) or reversible operators (e.g. le) included in their conditional expressions are double negations. Conway considers the following operators to be difficult to understand within unless and until:
! not !~ ne != < > <= >= <=> lt gt le ge cmp
This Policy is not configurable except for the standard options.
Perl::Critic::Policy::ControlStructures::ProhibitUnlessBlocks
Elliot Shank <perl@galumph.com>
<perl@galumph.com>
Copyright (c) 2007-2011 Elliot Shank.
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.
To install Perl::Critic, copy and paste the appropriate command in to your terminal.
cpanm
cpanm Perl::Critic
CPAN shell
perl -MCPAN -e shell install Perl::Critic
For more information on module installation, please visit the detailed CPAN module installation guide.