--- /dev/null
+##############################################################################
+# $URL: http://perlcritic.tigris.org/svn/perlcritic/trunk/Perl-Critic/lib/Perl/Critic/Policy/InputOutput/ProhibitReadlineInForLoop.pm $
+# $Date: 2008-07-03 10:19:10 -0500 (Thu, 03 Jul 2008) $
+# $Author: clonezone $
+# $Revision: 2489 $
+##############################################################################
+
+package Perl::Critic::Policy::InputOutput::ProhibitReadlineInForLoop;
+
+use 5.006001;
+use strict;
+use warnings;
+use Readonly;
+
+use Perl::Critic::Utils qw{ :severities };
+use base 'Perl::Critic::Policy';
+
+our $VERSION = '1.088';
+
+#-----------------------------------------------------------------------------
+
+Readonly::Scalar my $DESC => q{Readline inside "for" loop};
+Readonly::Scalar my $EXPL => [ 211 ];
+
+#-----------------------------------------------------------------------------
+
+sub supported_parameters { return () }
+sub default_severity { return $SEVERITY_HIGH }
+sub default_themes { return qw( core bugs pbp ) }
+sub applies_to { return qw( PPI::Structure::ForLoop) }
+
+#-----------------------------------------------------------------------------
+
+sub violates {
+ my ( $self, $elem, undef ) = @_;
+
+ if ( my $rl = $elem->find_first('PPI::Token::QuoteLike::Readline') ) {
+ return $self->violation( $DESC, $EXPL, $rl );
+ }
+
+ return; #ok!
+}
+
+1;
+
+__END__
+
+#-----------------------------------------------------------------------------
+
+=pod
+
+=head1 NAME
+
+Perl::Critic::Policy::InputOutput::ProhibitReadlineInForLoop - Write C<< while( $line = <> ){...} >> instead of C<< for(<>){...} >>.
+
+=head1 AFFILIATION
+
+This Policy is part of the core L<Perl::Critic> distribution.
+
+
+=head1 DESCRIPTION
+
+Using the readline operator in a C<for> or C<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 C<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
+
+
+=head1 CONFIGURATION
+
+This Policy is not configurable except for the standard options.
+
+
+=head1 AUTHOR
+
+Jeffrey Ryan Thalhammer <thaljef@cpan.org>
+
+=head1 COPYRIGHT
+
+Copyright (c) 2005-2008 Jeffrey Ryan Thalhammer. 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.
+
+=cut
+
+# Local Variables:
+# mode: cperl
+# cperl-indent-level: 4
+# fill-column: 78
+# indent-tabs-mode: nil
+# c-indentation-style: bsd
+# End:
+# ex: set ts=8 sts=4 sw=4 tw=78 ft=perl expandtab shiftround :