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


NAME
       Perl::Critic::Policy::InputOutput::ProhibitBarewordDirHandles - Write
       "opendir my $dh, $dirname;" instead of "opendir DH, $dirname;".

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

DESCRIPTION
       Using bareword symbols to refer to directory handles is particularly
       evil because they are global, and you have no idea if that symbol
       already points to some other file or directory 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 file handle or directory handle.
       Alternatively, see the IO::Handle or IO::Dir modules for an object-
       oriented approach.

           opendir DH, $some_dir;            #not ok
           opendir *DH, $some_dir;           #not ok
           opendir \*DH, $some_dir;          #not ok
           opendir local *DH, $some_dir;     #not ok
           opendir $dh, $some_dir;           #ok
           opendir my $dh, $some_dir;        #ok
           opendir our $dh, $some_dir;       #ok
           opendir local $dh, $some_dir;     #ok
           my $dh = IO::Dir->new($some_dir); #ok

       And Perl7 will probably drop support for bareword filehandles.

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

SEE ALSO
       Perl::Critic::Policy::InputOutput::ProhibitBarewordFileHandles::Perl::Critic::Policy::InputOutput::ProhibitBarewordFileHandles

       IO::Handle

       IO::Dir

AUTHOR
       Jeffrey Ryan Thalhammer <jeff@imaginative-software.com>,
       "github.com/pali", "github.com/raforg"

COPYRIGHT
       Copyright (c) 2005-2011, 2021 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::ProhibitBarewordDirHandles(3pm)