CPAN::...ements(3perl) Perl Programmers Reference Guide CPAN::...ements(3perl)
NAME
CPAN::Meta::Requirements - a set of version requirements for a CPAN dist
VERSION
version 2.143
SYNOPSIS
use CPAN::Meta::Requirements;
my $build_requires = CPAN::Meta::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 CPAN::Meta::Requirements object models a set of version constraints
like those specified in the META.yml or META.json files in CPAN
distributions, and as defined by CPAN::Meta::Spec. 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 = CPAN::Meta::Requirements->new;
This returns a new CPAN::Meta::Requirements object. It takes an
optional hash reference argument. Currently, only one key is supported:
• "bad_version_hook" -- if provided, when a version cannot be parsed
into a version object, this code reference will be called with the
invalid version string as first argument, and the module name as
second argument. It must return a valid version object.
All other keys are ignored.
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.
This method returns the requirements object.
add_maximum
$req->add_maximum( $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.
This method returns the requirements object.
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.
This method returns the requirements object.
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.
This method returns the requirements object.
version_range_for_module
$req->version_range_for_module( $another_req_object );
add_requirements
$req->add_requirements( $another_req_object );
This method adds all the requirements in the given
CPAN::Meta::Requirements object to the requirements object on which it
was called. If there are any conflicts, an exception is thrown.
This method returns the requirements object.
accepts_module
my $bool = $req->accepts_module($module => $version);
Given an module and version, this method returns true if the version
specification for the module accepts the provided version. In other
words, given:
Module => '>= 1.00, < 2.00'
We will accept 1.00 and 1.75 but not 0.50 or 2.00.
For modules that do not appear in the requirements, this method will
return true.
clear_requirement
$req->clear_requirement( $module );
This removes the requirement for a given module from the object.
This method returns the requirements object.
requirements_for_module
$req->requirements_for_module( $module );
This returns a string containing the version requirements for a given
module in the format described in CPAN::Meta::Spec or undef if the given
module has no requirements. This should only be used for informational
purposes such as error messages and should not be interpreted or used
for comparison (see "accepts_module" instead).
structured_requirements_for_module
$req->structured_requirements_for_module( $module );
This returns a data structure containing the version requirements for a
given module or undef if the given module has no requirements. This
should not be used for version checks (see "accepts_module" instead).
Added in version 2.134.
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.
is_simple
This method returns true if and only if all requirements are inclusive
minimums -- that is, if their string expression is just the version
number.
is_finalized
This method returns true if the requirements have been finalized by
having the "finalize" method called on them.
finalize
This method marks the requirements finalized. Subsequent attempts to
change the requirements will be fatal, if they would result in a change.
If they would not alter the requirements, they have no effect.
If a finalized set of requirements is cloned, the cloned requirements
are not also finalized.
as_string_hash
This returns a reference to a hash describing the requirements using the
strings in the CPAN::Meta::Spec specification.
For example after the following program:
my $req = CPAN::Meta::Requirements->new;
$req->add_minimum('CPAN::Meta::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:
{
'CPAN::Meta::Requirements' => '0.102',
'Library::Foo' => '>= 1.208, <= 2.206',
'Module::Bar' => '>= v1.2.3, != v1.2.8',
'Xyzzy' => '== 6.01',
}
add_string_requirement
$req->add_string_requirement('Library::Foo' => '>= 1.208, <= 2.206');
$req->add_string_requirement('Library::Foo' => v1.208);
This method parses the passed in string and adds the appropriate
requirement for the given module. A version can be a Perl "v-string".
It understands version ranges as described in the "Version Ranges" in
CPAN::Meta::Spec. For example:
1.3
>= 1.3
<= 1.3
== 1.3
!= 1.3
> 1.3
< 1.3
>= 1.3, != 1.5, <= 2.0
A version number without an operator is equivalent to specifying a
minimum (">="). Extra whitespace is allowed.
from_string_hash
my $req = CPAN::Meta::Requirements->from_string_hash( \%hash );
my $req = CPAN::Meta::Requirements->from_string_hash( \%hash, \%opts );
This is an alternate constructor for a CPAN::Meta::Requirements object.
It takes a hash of module names and version requirement strings and
returns a new CPAN::Meta::Requirements object. As with
add_string_requirement, a version can be a Perl "v-string". Optionally,
you can supply a hash-reference of options, exactly as with the "new"
method.
SUPPORT
Bugs / Feature Requests
Please report any bugs or feature requests through the issue tracker at
<https://github.com/Perl-Toolchain-Gang/CPAN-Meta-Requirements/issues>.
You will be notified automatically of any progress on your issue.
Source Code
This is open source software. The code repository is available for
public review and contribution under the terms of the license.
<https://github.com/Perl-Toolchain-Gang/CPAN-Meta-Requirements>
git clone https://github.com/Perl-Toolchain-Gang/CPAN-Meta-Requirements.git
AUTHORS
• David Golden <dagolden@cpan.org>
• Ricardo Signes <rjbs@cpan.org>
CONTRIBUTORS
• Ed J <mohawk2@users.noreply.github.com>
• Graham Knop <haarg@haarg.org>
• Karen Etheridge <ether@cpan.org>
• Leon Timmermans <fawaka@gmail.com>
• Paul Howarth <paul@city-fan.org>
• Ricardo Signes <rjbs@semiotic.systems>
• robario <webmaster@robario.com>
• Tatsuhiko Miyagawa <miyagawa@bulknews.net>
• Tatsuhiko Miyagawa <miyagawa@gmail.com>
COPYRIGHT AND LICENSE
This software is copyright (c) 2010 by David Golden and 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.
perl v5.40.1 2026-08-30 CPAN::...ements(3perl)
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