NAME

       Perl::Critic::Policy::InputOutput::ProhibitReadlineInForLoop - Write "while( $line = <>
       ){...}" instead of "for(<>){...}".

AFFILIATION

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

DESCRIPTION

       Using the readline operator in a "for" or "foreach" loop is very slow.  The iteration list
       of the loop creates a list context, which causes the readline operator to read the entire
       input stream before iteration even starts.  Instead, just use a "while" loop, which only
       reads one line at a time.

         for my $line ( <$file_handle> ){ do_something($line) }      #not ok
         while ( my $line = <$file_handle> ){ do_something($line) }  #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 v5.18.1                    Perl::Critic::Policy::InputOutput::ProhibitReadlineInForLoop(3pm)