NAME
Moose::Cookbook::Meta::Recipe5 - The "table" attribute as a metaclass trait
SYNOPSIS
package MyApp::Meta::Class::Trait::HasTable;
use Moose::Role;
has table =>
( is => 'rw',
isa => 'Str',
);
package Moose::Meta::Class::Custom::Trait::HasTable;
sub register_implementation { 'MyApp::Meta::Class::Trait::HasTable' }
package MyApp::User;
use Moose -traits => 'HasTable';
__PACKAGE__->table('User');DESCRIPTION
This recipe takes the metaclass table attribute and reimplements it as a metaclass trait. Traits are just roles that Moose applies to something for you. In this case, that "something" is the class's metaclass object.
The advantage of using traits is that it's easy to combine multiple traits, whereas combining multiple metaclasses can be tricky (which subclasses which?).
The disadvantage is that it's not easy to combine a trait with some sort of sugar (like our notional has_table sugar).
Using this Metaclass Trait in Practice
Once this trait has been applied to a metaclass, it looks exactly like the example we saw in Moose::Cookbook::Meta::Recipe4:
my $table = MyApp::User->meta()->table();SEE ALSO
Moose::Cookbook::Meta::Recipe3 - Labels implemented via attribute traits
Moose::Cookbook::Meta::Recipe4 - Adding a "table" attribute to the metaclass
AUTHOR
Dave Rolsky <autarch@urth.org>
COPYRIGHT AND LICENSE
Copyright 2006-2008 by Infinity Interactive, Inc.
This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.