NAME

       Perl::Critic::Policy::Miscellanea::TextDomainUnused - check for Locale::TextDomain imported but unused

DESCRIPTION

       This policy is part of the "Perl::Critic::Pulp" add-on.  It reports when you have "Locale::TextDomain"
       like

           use Locale::TextDomain ('MyMessageDomain');

       but then don't use any of its functions or variables

           __ __x __n __nx __xn
           __p __px __np __npx
           N__ N__n N__p N__np
           %__ $__

       "Locale::TextDomain" is not needed when not used, but it's also not actively harmful so this policy is
       only low severity and under the "cosmetic" theme (see "POLICY THEMES" in Perl::Critic).

       The check is good if you've got "Locale::TextDomain" as boilerplate code in most of your program, but in
       some modules it's unused.  You can remove it entirely from non-interactive modules, or comment it out
       from modules which might have messages but don't yet.  The best thing picked up is when your boilerplate
       has got into a programmatic module which shouldn't say anything at the user level.

       The saving from removing unused "Locale::TextDomain" is modest, just some imports and a hash entry
       holding the "textdomain" for the package.

       It's easy to imagine a general kind of "module imported but unused" policy check, but in practice its
       hard for perlcritic to know the automatic imports of every module, and quite a few modules have side-
       effects, so this TextDomainUnused policy just starts with one case of an unused include.

   Interpolated Variables
       The variables "%__" and "$__" are recognised in double-quote interpolated strings just by looking for a
       "$__" somewhere in the string, eg.

           print "*** $__{'A Message'} ***\n";  # ok

       It's not hard to trick the recognition with escapes, or a hash slice style, but in general taking any
       "$__" to be a TextDomain use is close enough.  (Perhaps in the future PPI will do a full parse of
       interpolated expressions.)

SEE ALSO

       Perl::Critic::Pulp, Perl::Critic, Locale::TextDomain,
       Perl::Critic::Policy::Miscellanea::TextDomainPlaceholders

HOME PAGE

       <http://user42.tuxfamily.org/perl-critic-pulp/index.html>

COPYRIGHT

       Copyright 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2019, 2021 Kevin Ryde

       Perl-Critic-Pulp is free software; you can redistribute it and/or modify it under the terms of the GNU
       General Public License as published by the Free Software Foundation; either version 3, or (at your
       option) any later version.

       Perl-Critic-Pulp is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without
       even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General
       Public License for more details.

       You should have received a copy of the GNU General Public License along with Perl-Critic-Pulp.  If not,
       see <http://www.gnu.org/licenses/>.

perl v5.32.1                                       2021-02-28              Perl::Critic::...extDomainUnused(3pm)