NAME

       Perl::Critic::Policy::InputOutput::ProhibitJoinedReadline - Use "local $/ = undef" or
       File::Slurp instead of joined readline.

AFFILIATION

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

DESCRIPTION

       It's really easy to slurp a whole filehandle in at once with "join q{}, <$fh">, but that's
       inefficient -- Perl goes to the trouble of splitting the file into lines only to have that
       work thrown away.

       To save performance, either slurp the filehandle without splitting like so:

         do { local $/ = undef; <$fh> }

       or use File::Slurp, which is even faster.

       Note that if the "ProhibitPunctuationVars" policy is also in effect, it will complain
       about the use of $/ in the line above.  In that case, write this instead:

         use English '-no_match_vars';

         do { local $INPUT_RECORD_SEPARATOR = undef; <$fh> };

CONFIGURATION

       This Policy is not configurable except for the standard options.

CAVEATS

       Due to a bug in the current version of PPI (v1.119_03) and earlier, the readline operator
       is often misinterpreted as less-than and greater-than operators after a comma.  Therefore,
       this policy only works well on the empty filehandle, "<>".  When PPI is fixed, this should
       just start working.

CREDITS

       Initial development of this policy was supported by a grant from the Perl Foundation.

AUTHOR

       Chris Dolan <cdolan@cpan.org>

COPYRIGHT

       Copyright (c) 2007-2011 Chris Dolan.  Many 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::ProhibitJoinedReadline(3pm)