perl::critic::policy::inputoutput::prohibitjoinedreadline(3pm) [debian man page]

Perl::Critic::Policy::InputOutput::ProhibitJoinedReadlinUsermContributed Perl DocumePerl::Critic::Policy::InputOutput::ProhibitJoinedReadline(3pm)

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 v5.14.2							    2012-06-07	    Perl::Critic::Policy::InputOutput::ProhibitJoinedReadline(3pm)

Perl::Critic::Policy::Variables::RequireLocalizedPunctuaUserVContributed PerlPerl::Critic::Policy::Variables::RequireLocalizedPunctuationVars(3pm)

NAME

       Perl::Critic::Policy::Variables::RequireLocalizedPunctuationVars - Magic variables should be assigned as "local".

AFFILIATION

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

DESCRIPTION

       Punctuation variables (and their English.pm equivalents) are global variables.  Messing with globals is dangerous in a complex program as
       it can lead to very subtle and hard to fix bugs.  If you must change a magic variable in a non-trivial program, do it in a local scope.

       For example, to slurp a filehandle into a scalar, it's common to set the record separator to undef instead of a newline.  If you choose to
       do this (instead of using File::Slurp!) then be sure to localize the global and change it for as short a time as possible.

	   # BAD:
	   $/ = undef;
	   my $content = <$fh>;

	   # BETTER:
	   my $content;
	   {
	       local $/ = undef;
	       $content = <$fh>;
	   }

	   # A popular idiom:
	   my $content = do { local $/ = undef; <$fh> };

       This policy also allows the use of "my".  Perl prevents using "my" with "proper" punctuation variables, but allows $a, @ARGV, the names
       declared by English, etc.  This is not a good coding practice, however it is not the concern of this specific policy to complain about
       that.

       There are exemptions for $_ and @_, and the English equivalent $ARG.

CONFIGURATION

       You can configure your own exemptions using the "allow" option:

	   [Variables::RequireLocalizedPunctuationVars]
	   allow = @ARGV $ARGV

       These are added to the default exemptions.

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 v5.14.2							    2012-06-0Perl::Critic::Policy::Variables::RequireLocalizedPunctuationVars(3pm)