#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