Perl::Critic::Policy::Modules::RequireExplicitPackage - Always make the package explicit.


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


In general, the first statement of any Perl module or library should be a package statement. Otherwise, all the code that comes before the package statement is getting executed in the caller's package, and you have no idea who that is. Good encapsulation and common decency require your module to keep its innards to itself.

There are some valid reasons for not having a package statement at all. But make sure you understand them before assuming that you should do it too.

The maximum number of violations per document for this policy defaults to 1.


As for programs, most people understand that the default package is main, so this Policy doesn't apply to files that begin with a perl shebang. If you want to require an explicit package declaration in all files, including programs, then add the following to your .perlcriticrc file

    exempt_scripts = 0

Some users may find it desirable to exempt the load of specific modules from this policy. For example, Perl does not support Unicode module names because of portability problems. Users who are not concerned about this and intend to use UTF-8 module names will need to specify use utf8; before the package declaration. To do this, add the following to your .perlcriticrc file

    allow_import_of = utf8

The allow_import_of configuration option takes multiple module names, separated by spaces.


This policy was formerly called ProhibitUnpackagedCode which sounded a bit odd. If you get lots of "Cannot load policy module" errors, then you probably need to change ProhibitUnpackagedCode to RequireExplicitPackage in your .perlcriticrc file.


Jeffrey Ryan Thalhammer <>


Copyright (c) 2005-2011 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. The full text of this license can be found in the LICENSE file included with this module.