/ 
Version-Requirements-0.100520
River stage zero No dependents
/ Version::Requirements

NAME

Version::Requirements - a set of version requirements for a CPAN dist

VERSION

version 0.100520

SYNOPSIS

use Version::Requirements;

my $build_requires = Version::Requirements->new;

$build_requires->add_minimum('Library::Foo' => 1.208);

$build_requires->add_minimum('Library::Foo' => 2.602);

$build_requires->add_minimum('Module::Bar'  => 'v1.2.3');

$METAyml->{build_requires} = $build_requires->as_string_hash;

DESCRIPTION

A Version::Requirements object models a set of version constraints like those specified in the META.yml or META.json files in CPAN distributions. It can be built up by adding more and more constraints, and it will reduce them to the simplest representation.

Logically impossible constraints will be identified immediately by thrown exceptions.

METHODS

new

my $req = Version::Requirements->new;

This returns a new Version::Requirements object. It ignores any arguments given.

add_minimum

$req->add_minimum( $module => $version );

This adds a new minimum version requirement. If the new requirement is redundant to the existing specification, this has no effect.

Minimum requirements are inclusive. $version is required, along with any greater version number.

add_maximum

$req->add_minimum( $module => $version );

This adds a new maximum version requirement. If the new requirement is redundant to the existing specification, this has no effect.

Maximum requirements are inclusive. No version strictly greater than the given version is allowed.

add_exclusion

$req->add_exclusion( $module => $version );

This adds a new excluded version. For example, you might use these three method calls:

$req->add_minimum( $module => '1.00' );
$req->add_maximum( $module => '1.82' );

$req->add_exclusion( $module => '1.75' );

Any version between 1.00 and 1.82 inclusive would be acceptable, except for 1.75.

exact_version

$req->exact_version( $module => $version );

This sets the version required for the given module to exactly the given version. No other version would be considered acceptable.

add_requirements

$req->add_requirements( $another_req_object );

This method adds all the requirements in the given Version::Requirements object to the requirements object on which it was called. If there are any conflicts, an exception is thrown.

clear_requirement

$req->clear_requirement( $module );

This removes the requirement for a given module from the object.

required_modules

This method returns a list of all the modules for which requirements have been specified.

clone

$req->clone;

This method returns a clone of the invocant. The clone and the original object can then be changed independent of one another.

as_string_hash

This returns a reference to a hash describing the requirements using the strings in the META.yml specification.

For example after the following program:

my $req = Version::Requirements->new;

$req->add_minimum('Version::Requirements' => 0.102);

$req->add_minimum('Library::Foo' => 1.208);

$req->add_maximum('Library::Foo' => 2.602);

$req->add_minimum('Module::Bar'  => 'v1.2.3');

$req->add_exclusion('Module::Bar'  => 'v1.2.8');

$req->exact_version('Xyzzy'  => '6.01');

my $hashref = $req->as_string_hash;

$hashref would contain:

{
  'Version::Requirements' => '0.102',
  'Library::Foo' => '>= 1.208, <= 2.206',
  'Module::Bar'  => '>= v1.2.3, != v1.2.8',
  'Xyzzy'        => '== 6.01',
}

from_string_hash

my $req = Version::Requirements->from_string_hash( \%hash );

This is an alternate constructor for a Version::Requirements object. It takes a hash of module names and version requirement strings and returns a new Version::Requirements object.

AUTHOR

Ricardo Signes <rjbs@cpan.org>

COPYRIGHT AND LICENSE

This software is copyright (c) 2010 by Ricardo Signes.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.