| Perl::Critic::Policy::InputOutput::ProhibitReadlineInForLoop(3pm) | User Contributed Perl Documentation | Perl::Critic::Policy::InputOutput::ProhibitReadlineInForLoop(3pm) |
Perl::Critic::Policy::InputOutput::ProhibitReadlineInForLoop - Write "while( $line = <> ){...}" instead of "for(<>){...}".
This Policy is part of the core Perl::Critic distribution.
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
This Policy is not configurable except for the standard options.
Jeffrey Ryan Thalhammer <jeff@imaginative-software.com>
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.
| 2023-01-15 | perl v5.36.0 |