Perl::Critic::Policy::BuiltinFunctions::ProhibitVoidMap(User Contributed Perl DocumentPerl::Critic::Policy::BuiltinFunctions::ProhibitVoidMap(3pm)

NAME

       Perl::Critic::Policy::BuiltinFunctions::ProhibitVoidMap - Don't use "map" in void contexts.

AFFILIATION

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

DESCRIPTION

       "map" and "grep" are intended to be pure functions, not mutators.  If you want to iterate with side-effects, then you should use a proper
       "for" or "foreach" loop.

	   grep{ print frobulate($_) } @list;		#not ok
	   print map{ frobulate($_) } @list;		#ok

	   grep{ $_ = lc $_ } @list;			#not ok
	   for( @list ){ $_ = lc $_  }; 		#ok

	   map{ push @frobbed, frobulate($_) } @list;	#not ok
	   @frobbed = map { frobulate($_) } @list;	#ok

CONFIGURATION

       This Policy is not configurable except for the standard options.

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 v5.14.2							    2012-06-07	      Perl::Critic::Policy::BuiltinFunctions::ProhibitVoidMap(3pm)