Perl::Critic::Policy::Modules::RequireVersionVar(3pm)	User Contributed Perl Documentation  Perl::Critic::Policy::Modules::RequireVersionVar(3pm)

NAME

       Perl::Critic::Policy::Modules::RequireVersionVar - Give every module a "$VERSION" number.

AFFILIATION

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

DESCRIPTION

       Every Perl file (modules, libraries, and programs) should have a package-scoped $VERSION variable.  The $VERSION allows clients to insist
       on a particular revision of your file like this:

	   use SomeModule 2.4;	#Only loads version 2.4

       This Policy scans your file for any package variable named $VERSION.  I'm assuming that you are using "strict", so you'll have to declare
       it like one of these:

	   our $VERSION = 1.0611;
	   $MyPackage::VERSION = 1.061;
	   use vars qw($VERSION);
	   use version; our $VERSION = qv(1.0611);

       Perl's version system does not recognize lexical variables such as

	   my $VERSION = 1.0611;

       so they are not accepted by this policy.

       A common practice is to use the "$Revision: 4106 $" keyword to automatically define the $VERSION variable like this:

	   our ($VERSION) = '$Revision: 4106 $' =~ m{ $Revision: s+ (S+) }x;

CONFIGURATION

       This Policy is not configurable except for the standard options.

NOTES

       Conway recommends using the "version" pragma instead of raw numbers or 'v-strings.'  However, this Policy only insists that the $VERSION be
       defined somehow.  I may try to extend this in the future.

TO DO

       Add check that $VERSION is independently evaluatable.  In particular, prohibit this:

	   our $VERSION = $Other::Module::VERSION;

       This doesn't work because PAUSE and other tools literally copy your version declaration out of your module and evaluates it in isolation,
       at which point there's nothing in "Other::Module", and so the $VERSION is undefined.

AUTHOR

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

COPYRIGHT

       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.

perl v5.14.2							    2012-06-07		     Perl::Critic::Policy::Modules::RequireVersionVar(3pm)