Perl::Critic::Policy::InputOutput::ProhibitBarewordFileHandles(3pm)
                                           User Contributed Perl Documentation


NAME
       Perl::Critic::Policy::InputOutput::ProhibitBarewordFileHandles - Write
       "open my $fh, q{<}, $filename;" instead of "open FH, q{<}, $filename;".

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

DESCRIPTION
       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 "local"izing 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.

           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 also applies to the "sysopen" function as well.

CONFIGURATION
       This Policy is not configurable except for the standard options.

SEE ALSO
       IO::Handle

       IO::File

AUTHOR
       Jeffrey Ryan Thalhammer <jeff@imaginative-software.com>

COPYRIGHT
       Copyright (c) 2005-2022 Imaginative Software Systems.  All rights
       reserved.

       This program is free software; you can redistribute it and/or modify it
       under the same terms as Perl itself.

perl v5.38.0                      2023-07-26
           Perl::Critic::Policy::InputOutput::ProhibitBarewordFileHandles(3pm)