Section: User Contributed Perl Documentation (3)
Moose::Cookbook::Legacy::Table_ClassMetaclass - Adding a "table" attribute to the metaclass
has table => (
is => 'rw',
isa => 'Str',
WARNING: Subclassing metaclasses (as opposed to providing metaclass traits)
is strongly discouraged. This recipe is provided solely for reference when
encountering older code that does this.
In this recipe, we'll create a new metaclass which has a ``table''
attribute. This metaclass is for classes associated with a DBMS table,
as one might do for an ORM.
In this example, the table name is just a string, but in a real ORM
the table might be an object describing the table.
This really is as simple as the recipe ``SYNOPSIS''
shows. The trick
is getting your classes to use this metaclass, and providing some sort
of sugar for declaring the table. This is covered in
Moose::Cookbook::Extending::Recipe2, which shows how to make a
module like "Moose.pm"
itself, with sugar like "has_table()"
Using this Metaclass in Practice
Accessing this new "table"
attribute is quite simple. Given a class
, we could simply write the following:
my $table = MyApp::User->meta->table;
As long as "MyApp::User" has arranged to use "MyApp::Meta::Class" as
its metaclass, this method call just works. If we want to be more
careful, we can check the metaclass's class:
$table = MyApp::User->meta->table
Creating custom metaclass is trivial. Using it is a little harder, and
is covered in other recipes. We will also talk about applying traits
to a class metaclass, which is a more flexible and cooperative
Moose::Cookbook::Meta::Recipe5 - The ``table'' attribute implemented
as a metaclass trait
Moose::Cookbook::Extending::Recipe2 - Acting like Moose.pm and
providing sugar Moose-style
Stevan Little <firstname.lastname@example.org>
Dave Rolsky <email@example.com>
Jesse Luehrs <firstname.lastname@example.org>
Shawn M Moore <email@example.com>
יובל קוג'מן (Yuval Kogman) <firstname.lastname@example.org>
Karen Etheridge <email@example.com>
Florian Ragwitz <firstname.lastname@example.org>
Hans Dieter Pearcey <email@example.com>
Chris Prather <firstname.lastname@example.org>
Matt S Trout <email@example.com>
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.