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Perl::CriPerl::Critic:UseriContributednPerlrDocumentationireConstantVersion(3)

NAME
       Perl::Critic::Policy::ValuesAndExpressions::RequireConstantVersion -
       Require $VERSION	to be a	constant rather	than a computed	value.

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

DESCRIPTION
       The $VERSION variable of	a module should	be a simple constant - either
       a number, a single-quotish string, or a 'use version' object. In	the
       latter case the 'use version;' must appear on the same line as the
       object construction.

       Computing the version has problems of various severities.

       The most	benign violation is computing the version from (e.g.) a
       Subversion revision number:

	   our ($VERSION) = q$REVISION:	42$ =~ /(\d+)/;

       The problem here	is that	the version is tied to a single	repository.
       The code	can not	be moved to another repository (even of	the same type)
       without changing	its version, possibly in the wrong direction.

       This policy accepts v-strings ("v1.2.3" or just plain 1.2.3), since
       these are already flagged by
       Perl::Critic::Policy::ValuesAndExpressions::ProhibitVersionStrings.

CONFIGURATION
       The proper way to set a module's	$VERSION to a "version"	object is to
       "use version;" on the same line of code that assigns the	value of
       $VERSION.  That way, ExtUtils::MakeMaker	and Module::Build can extract
       the version when	packaging the module for CPAN. By default, this	policy
       declares	an error if this is not	done.

       Should you wish to allow	version	objects	without	loading	the version
       module on the same line,	add the	following to your configuration	file:

	   [ValuesAndExpressions::RequireConstantVersion]
	   allow_version_without_use_on_same_line = 1

CAVEATS
       There will be false negatives if	the $VERSION appears on	the left-hand
       side of a list assignment that assigns to more than one variable, or to
       "undef".

       There may be false positives if the $VERSION is assigned	the value of a
       here document. This will	probably remain	the case until
       PPI::Token::HereDoc acquires the	relevant portions of the
       PPI::Token::Quote interface.

       There will be false positives if	$VERSION is assigned the value of a
       constant	created	by the Readonly	module or the constant pragma, because
       the necessary infrastructure appears not	to exist, and the author of
       the present module lacked the knowledge/expertise/gumption to put it in
       place.

       Currently the idiom

	   our $VERSION	= '1.005_05';
	   $VERSION = eval $VERSION;

       will produce a violation	on the second line of the example.

AUTHOR
       Thomas R. Wyant,	III wyant at cpan dot org

COPYRIGHT
       Copyright (c) 2009-2011 Tom Wyant.

       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 v5.2Perl::Critic::Policy::ValuesAndExpressions::RequireConstantVersion(3)

NAME | AFFILIATION | DESCRIPTION | CONFIGURATION | CAVEATS | AUTHOR | COPYRIGHT

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