/ 
Moose-2.1208
River stage four • 2934 direct dependents • 4029 total dependents
/ Moose::Meta::Role

NAME

Moose::Meta::Role - The Moose Role metaclass

VERSION

version 2.1208

DESCRIPTION

This class is a subclass of Class::MOP::Module that provides additional Moose-specific functionality.

Its API looks a lot like Moose::Meta::Class, but internally it implements many things differently. This may change in the future.

INHERITANCE

Moose::Meta::Role is a subclass of Class::MOP::Module.

METHODS

Construction

Moose::Meta::Role->initialize($role_name)

This method creates a new role object with the provided name.

Moose::Meta::Role->combine( [ $role => { ... } ], [ $role ], ... )

This method accepts a list of array references. Each array reference should contain a role name or Moose::Meta::Role object as its first element. The second element is an optional hash reference. The hash reference can contain -excludes and -alias keys to control how methods are composed from the role.

The return value is a new Moose::Meta::Role::Composite that represents the combined roles.

$metarole->composition_class_roles

When combining multiple roles using combine, this method is used to obtain a list of role names to be applied to the Moose::Meta::Role::Composite instance returned by combine. The default implementation returns an empty list. Extensions that need to hook into role combination may wrap this method to return additional role names.

Moose::Meta::Role->create($name, %options)

This method is identical to the Moose::Meta::Class create method.

Moose::Meta::Role->create_anon_role

This method is identical to the Moose::Meta::Class create_anon_class method.

$metarole->is_anon_role

Returns true if the role is an anonymous role.

$metarole->consumers

Returns a list of names of classes and roles which consume this role.

Role application

$metarole->apply( $thing, @options )

This method applies a role to the given $thing. That can be another Moose::Meta::Role, object, a Moose::Meta::Class object, or a (non-meta) object instance.

The options are passed directly to the constructor for the appropriate Moose::Meta::Role::Application subclass.

Note that this will apply the role even if the $thing in question already does this role. "does_role" in Moose::Util is a convenient wrapper for finding out if role application is necessary.

Roles and other roles

$metarole->get_roles

This returns an array reference of roles which this role does. This list may include duplicates.

$metarole->calculate_all_roles

This returns a unique list of all roles that this role does, and all the roles that its roles do.

$metarole->does_role($role)

Given a role name or Moose::Meta::Role object, returns true if this role does the given role.

$metarole->add_role($role)

Given a Moose::Meta::Role object, this adds the role to the list of roles that the role does.

$metarole->get_excluded_roles_list

Returns a list of role names which this role excludes.

$metarole->excludes_role($role_name)

Given a role name, returns true if this role excludes the named role.

$metarole->add_excluded_roles(@role_names)

Given one or more role names, adds those roles to the list of excluded roles.

Methods

The methods for dealing with a role's methods are all identical in API and behavior to the same methods in Class::MOP::Class.

$metarole->method_metaclass

Returns the method metaclass name for the role. This defaults to Moose::Meta::Role::Method.

$metarole->get_method($name)
$metarole->has_method($name)
$metarole->add_method( $name, $body )
$metarole->get_method_list
$metarole->find_method_by_name($name)

These methods are all identical to the methods of the same name in Class::MOP::Package

Attributes

As with methods, the methods for dealing with a role's attribute are all identical in API and behavior to the same methods in Class::MOP::Class.

However, attributes stored in this class are not stored as objects. Rather, the attribute definition is stored as a hash reference. When a role is composed into a class, this hash reference is passed directly to the metaclass's add_attribute method.

This is quite likely to change in the future.

$metarole->get_attribute($attribute_name)
$metarole->has_attribute($attribute_name)
$metarole->get_attribute_list
$metarole->add_attribute($name, %options)
$metarole->remove_attribute($attribute_name)

Overload introspection and creation

The methods for dealing with a role's overloads are all identical in API and behavior to the same methods in Class::MOP::Class. Note that these are not particularly useful (yet), because overloads do not participate in role composition.

$metarole->is_overloaded
$metarole->get_overloaded_operator($op)
$metarole->has_overloaded_operator($op)
$metarole->get_overload_list
$metarole->get_all_overloaded_operators
$metarole->add_overloaded_operator($op, $impl)
$metarole->remove_overloaded_operator($op)

Required methods

$metarole->get_required_method_list

Returns the list of methods required by the role.

$metarole->requires_method($name)

Returns true if the role requires the named method.

$metarole->add_required_methods(@names)

Adds the named methods to the role's list of required methods.

$metarole->remove_required_methods(@names)

Removes the named methods from the role's list of required methods.

$metarole->add_conflicting_method(%params)

Instantiate the parameters as a Moose::Meta::Role::Method::Conflicting object, then add it to the required method list.

Method modifiers

These methods act like their counterparts in Class::MOP::Class and Moose::Meta::Class.

However, method modifiers are simply stored internally, and are not applied until the role itself is applied to a class.

$metarole->add_after_method_modifier($method_name, $method)
$metarole->add_around_method_modifier($method_name, $method)
$metarole->add_before_method_modifier($method_name, $method)
$metarole->add_override_method_modifier($method_name, $method)

These methods all add an appropriate modifier to the internal list of modifiers.

$metarole->has_after_method_modifiers
$metarole->has_around_method_modifiers
$metarole->has_before_method_modifiers
$metarole->has_override_method_modifier

Return true if the role has any modifiers of the given type.

$metarole->get_after_method_modifiers($method_name)
$metarole->get_around_method_modifiers($method_name)
$metarole->get_before_method_modifiers($method_name)

Given a method name, returns a list of the appropriate modifiers for that method.

$metarole->get_override_method_modifier($method_name)

Given a method name, returns the override method modifier for that method, if it has one.

Introspection

Moose::Meta::Role->meta

This will return a Class::MOP::Class instance for this class.

BUGS

See "BUGS" in Moose for details on reporting bugs.

AUTHORS

  • Stevan Little <stevan.little@iinteractive.com>

  • Dave Rolsky <autarch@urth.org>

  • Jesse Luehrs <doy@tozt.net>

  • Shawn M Moore <code@sartak.org>

  • יובל קוג'מן (Yuval Kogman) <nothingmuch@woobling.org>

  • Karen Etheridge <ether@cpan.org>

  • Florian Ragwitz <rafl@debian.org>

  • Hans Dieter Pearcey <hdp@weftsoar.net>

  • Chris Prather <chris@prather.org>

  • Matt S Trout <mst@shadowcat.co.uk>

COPYRIGHT AND LICENSE

This software is copyright (c) 2006 by Infinity Interactive, Inc..

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