Perl::Critic::Policy::InputOutput::ProhibitBarewordDirHandles - Write opendir my $dh, $dirname; instead of opendir DH, $dirname;.
opendir my $dh, $dirname;
opendir DH, $dirname;
This Policy is part of the core Perl::Critic distribution.
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 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 file handle or directory handle. Alternatively, see the IO::Handle or IO::Dir modules for an object-oriented approach.
local
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.
This Policy is not configurable except for the standard options.
Perl::Critic::Policy::InputOutput::ProhibitBarewordFileHandles::Perl::Critic::Policy::InputOutput::ProhibitBarewordFileHandles
IO::Handle
IO::Dir
Jeffrey Ryan Thalhammer <jeff@imaginative-software.com>, github.com/pali, github.com/raforg
github.com/pali
github.com/raforg
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cpanm
cpanm Perl::Critic
CPAN shell
perl -MCPAN -e shell install Perl::Critic
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