Perl::Critic::Policy::InputOutput::ProhibitBarewordFileHandles - Write open my $fh, q{<}, $filename; instead of open FH, q{<}, $filename;.
open my $fh, q{<}, $filename;
open FH, q{<}, $filename;
This Policy is part of the core Perl::Critic distribution.
Using bareword symbols to refer to file handles is particularly evil because they are global, and you have no idea if that symbol already points to some other file handle. You can mitigate some of that risk by localizing the symbol first, but that's pretty ugly. Since Perl 5.6, you can use an undefined scalar variable as a lexical reference to an anonymous filehandle. Alternatively, see the IO::Handle or IO::File or FileHandle modules for an object-oriented approach.
local
open FH, '<', $some_file; #not ok open my $fh, '<', $some_file; #ok my $fh = IO::File->new($some_file); #ok
There are three exceptions: STDIN, STDOUT and STDERR. These three standard filehandles are always package variables.
This Policy is not configurable except for the standard options.
IO::Handle
IO::File
Jeffrey Ryan Thalhammer <thaljef@cpan.org>
Copyright (C) 2005-2007 Jeffrey Ryan Thalhammer. All rights reserved.
This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.
To install Perl::Critic, copy and paste the appropriate command in to your terminal.
cpanm
cpanm Perl::Critic
CPAN shell
perl -MCPAN -e shell install Perl::Critic
For more information on module installation, please visit the detailed CPAN module installation guide.