perl::critic::policy::valuesandexpressions::prohibitcomplexversi(3pm) [debian man page]

Perl::Critic::Policy::ValuesAndExpressions::ProhibitCompUsereContributed PePerl::Critic::Policy::ValuesAndExpressions::ProhibitComplexVersion(3pm)

NAME

       Perl::Critic::Policy::ValuesAndExpressions::ProhibitComplexVersion - Prohibit version values from outside the module.

AFFILIATION

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

DESCRIPTION

       One tempting way to keep a group of related modules at the same version number is to have all of them import the version number from a
       designated module. For example, module "Foo::Master" could be the version master for the "Foo" package, and all other modules could use its
       $VERSION by

	   use Foo::Master; our $VERSION = $Foo::Master::VERSION;

       This turns out not to be a good idea, because all sorts of unintended things can happen - anything from unintended version number changes
       to denial-of-service attacks (since "Foo::Master" is executed by the 'use').

       This policy examines statements that assign to $VERSION, and declares a violation under two circumstances: first, if that statement uses a
       fully-qualified symbol that did not originate in a package declared in the file; second if there is a "use" statement on the same line that
       makes the assignment.

       By default, an exception is made for "use version;" because of its recommendation by Perl Best Practices. See the "forbid_use_version"
       configuration variable if you do not want an exception made for "use version;".

CONFIGURATION

       The construction

	   use version; our $VERSION = qv('1.2.3');

       is exempt from this policy by default, because it is recommended by Perl Best Practices. Should you wish to identify "use version;" as a
       violation, add the following to your perlcriticrc file:

	   [ValuesAndExpressions::ProhibitComplexVersion]
	   forbid_use_version = 1

CAVEATS

       This code assumes that the hallmark of a violation is a 'use' on the same line as the $VERSION assignment, because that is the way to have
       it seen by ExtUtils::MakeMaker->parse_version(). Other ways to get a version value from outside the module can be imagined, and this policy
       is currently oblivious to them.

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 v5.14.2							    2012-06Perl::Critic::Policy::ValuesAndExpressions::ProhibitComplexVersion(3pm)

Perl::Critic::Policy::ValuesAndExpressions::RequireConstUsereContributed PerlPerl::Critic::Policy::ValuesAndExpressions::RequireConstantVersion(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 v5.16.3							    2014-06-0Perl::Critic::Policy::ValuesAndExpressions::RequireConstantVersion(3)