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Moose::Role(3)                       User Contributed Perl Documentation                      Moose::Role(3)



NAME
       Moose::Role - The Moose Role

VERSION
       version 2.0604

SYNOPSIS
         package Eq;
         use Moose::Role; # automatically turns on strict and warnings

         requires 'equal';

         sub no_equal {
             my ($self, $other) = @_;
             !$self->equal($other);
         }

         # ... then in your classes

         package Currency;
         use Moose; # automatically turns on strict and warnings

         with 'Eq';

         sub equal {
             my ($self, $other) = @_;
             $self->as_float == $other->as_float;
         }

         # ... and also

         package Comparator;
         use Moose;

         has compare_to => (
             is      => 'ro',
             does    => 'Eq',
             handles => 'Eq',
         );

         # ... which allows

         my $currency1 = Currency->new(...);
         my $currency2 = Currency->new(...);
         Comparator->new(compare_to => $currency1)->equal($currency2);

DESCRIPTION
       The concept of roles is documented in Moose::Manual::Roles. This document serves as API
       documentation.

EXPORTED FUNCTIONS
       Moose::Role currently supports all of the functions that Moose exports, but differs slightly in how
       some items are handled (see "CAVEATS" below for details).

       Moose::Role also offers two role-specific keyword exports:

       requires (@method_names)
           Roles can require that certain methods are implemented by any class which "does" the role.

           Note that attribute accessors also count as methods for the purposes of satisfying the
           requirements of a role.

       excludes (@role_names)
           Roles can "exclude" other roles, in effect saying "I can never be combined with these
           @role_names". This is a feature which should not be used lightly.

   unimport
       Moose::Role offers a way to remove the keywords it exports, through the "unimport" method. You simply
       have to say "no Moose::Role" at the bottom of your code for this to work.

METACLASS
       When you use Moose::Role, you can specify traits which will be applied to your role metaclass:

           use Moose::Role -traits => 'My::Trait';

       This is very similar to the attribute traits feature. When you do this, your class's "meta" object
       will have the specified traits applied to it. See "Metaclass and Trait Name Resolution" in Moose for
       more details.

APPLYING ROLES
       In addition to being applied to a class using the 'with' syntax (see Moose::Manual::Roles) and using
       the Moose::Util 'apply_all_roles' method, roles may also be applied to an instance of a class using
       Moose::Util 'apply_all_roles' or the role's metaclass:

          MyApp::Test::SomeRole->meta->apply( $instance );

       Doing this creates a new, mutable, anonymous subclass, applies the role to that, and reblesses. In a
       debugger, for example, you will see class names of the form " Moose::Meta::Class::__ANON__::SERIAL::6
       ", which means that doing a 'ref' on your instance may not return what you expect. See Moose::Object
       for 'DOES'.

       Additional params may be added to the new instance by providing 'rebless_params'. See
       Moose::Meta::Role::Application::ToInstance.

CAVEATS
       Role support has only a few caveats:

       •   Roles cannot use the "extends" keyword; it will throw an exception for now.  The same is true of
           the "augment" and "inner" keywords (not sure those really make sense for roles). All other Moose
           keywords will be deferred so that they can be applied to the consuming class.

       •   Role composition does its best to not be order-sensitive when it comes to conflict resolution and
           requirements detection. However, it is order-sensitive when it comes to method modifiers. All
           before/around/after modifiers are included whenever a role is composed into a class, and then
           applied in the order in which the roles are used. This also means that there is no conflict for
           before/around/after modifiers.

           In most cases, this will be a non-issue; however, it is something to keep in mind when using
           method modifiers in a role. You should never assume any ordering.

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

AUTHOR
       Moose is maintained by the Moose Cabal, along with the help of many contributors. See "CABAL" in
       Moose and "CONTRIBUTORS" in Moose for details.

COPYRIGHT AND LICENSE
       This software is copyright (c) 2012 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.



perl v5.16.2                                     2012-09-19                                   Moose::Role(3)