NAME¶

Mouse::Util::MetaRole - Apply roles to any metaclass, as well as the object base class

SYNOPSIS¶

  package MyApp::Mouse;
  use Mouse ();
  use Mouse::Exporter;
  use Mouse::Util::MetaRole;
  use MyApp::Role::Meta::Class;
  use MyApp::Role::Meta::Method::Constructor;
  use MyApp::Role::Object;
  Mouse::Exporter->setup_import_methods( also => 'Mouse' );
  sub init_meta {
      shift;
      my %args = @_;
      Mouse->init_meta(%args);
      Mouse::Util::MetaRole::apply_metaroles(
          for             => $args{for_class},
          class_metaroles => {
              class       => ['MyApp::Role::Meta::Class'],
              constructor => ['MyApp::Role::Meta::Method::Constructor'],
          },
      );
      Mouse::Util::MetaRole::apply_base_class_roles(
          for   => $args{for_class},
          roles => ['MyApp::Role::Object'],
      );
      return $args{for_class}->meta();
  }

DESCRIPTION¶

This utility module is designed to help authors of Mouse extensions write extensions that are able to cooperate with other Mouse extensions. To do this, you must write your extensions as roles, which can then be dynamically applied to the caller's metaclasses.

This module makes sure to preserve any existing superclasses and roles already set for the meta objects, which means that any number of extensions can apply roles in any order.

USAGE¶

It is very important that you only call this module's functions when your module is imported by the caller. The process of applying roles to the metaclass reinitializes the metaclass object, which wipes out any existing attributes already defined. However, as long as you do this when your module is imported, the caller should not have any attributes defined yet.

The easiest way to ensure that this happens is to use Mouse::Exporter, which can generate the appropriate "init_meta" method for you, and make sure it is called when imported.

FUNCTIONS¶

This module provides two functions.

SEE ALSO¶

Moose::Util::MetaRole