NAME

       Perl::Critic::Policy::InputOutput::ProhibitExplicitStdin - Use "<>" or "<ARGV>" or a
       prompting module instead of "<STDIN>".

AFFILIATION

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

DESCRIPTION

       Perl has a useful magic filehandle called *ARGV that checks the command line and if there
       are any arguments, opens and reads those as files.  If there are no arguments, *ARGV
       behaves like *STDIN instead.  This behavior is almost always what you want if you want to
       create a program that reads from "STDIN".  This is often written in one of the following
       two equivalent forms:

         while (<ARGV>) {
           # ... do something with each input line ...
         }
         # or, equivalently:
         while (<>) {
           # ... do something with each input line ...
         }

       If you want to prompt for user input, try special purpose modules like IO::Prompt.

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 misses important cases like

         my $content = join '', <STDIN>;

       because it interprets that line as the nonsensical statement:

         my $content = join '', < STDIN >;

       When that PPI bug is fixed, this policy should start catching those violations
       automatically.

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::ProhibitExplicitStdin(3pm)