Perl::Critic::Policy::InputOutput::ProhibitReadlineInForLoop3pm
Write "while( $line = <> ){...}" instead of "for(<>){...}".
Affiliation
This Policy is part of the core Perl::Critic distribution.
Overview
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 okwhile ( my $line = <$file_handle> ){ do_something($line) } #ok
Configuration
This Policy is not configurable except for the standard options.
Releases
10 releases since Debian 5.0 (Lenny); the text changed 9 times.