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|
# PODNAME: Moose::Cookbook::Legacy::Table_ClassMetaclass
# ABSTRACT: Adding a "table" attribute to the metaclass
__END__
=pod
=encoding UTF-8
=head1 NAME
Moose::Cookbook::Legacy::Table_ClassMetaclass - Adding a "table" attribute to the metaclass
=head1 VERSION
version 2.1405
=head1 SYNOPSIS
package MyApp::Meta::Class;
use Moose;
extends 'Moose::Meta::Class';
has table => (
is => 'rw',
isa => 'Str',
);
=head1 DESCRIPTION
B<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.
=head1 THE METACLASS
This really is as simple as the recipe L</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
L<Moose::Cookbook::Extending::Recipe2>, which shows how to make a
module like C<Moose.pm> itself, with sugar like C<has_table()>.
=head2 Using this Metaclass in Practice
Accessing this new C<table> attribute is quite simple. Given a class
named C<MyApp::User>, we could simply write the following:
my $table = MyApp::User->meta->table;
As long as C<MyApp::User> has arranged to use C<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
if MyApp::User->meta->isa('MyApp::Meta::Class');
=head1 CONCLUSION
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
implementation.
=head1 SEE ALSO
L<Moose::Cookbook::Meta::Recipe5> - The "table" attribute implemented
as a metaclass trait
L<Moose::Cookbook::Extending::Recipe2> - Acting like Moose.pm and
providing sugar Moose-style
=head1 AUTHORS
=over 4
=item *
Stevan Little <stevan.little@iinteractive.com>
=item *
Dave Rolsky <autarch@urth.org>
=item *
Jesse Luehrs <doy@tozt.net>
=item *
Shawn M Moore <code@sartak.org>
=item *
יובל קוג'מן (Yuval Kogman) <nothingmuch@woobling.org>
=item *
Karen Etheridge <ether@cpan.org>
=item *
Florian Ragwitz <rafl@debian.org>
=item *
Hans Dieter Pearcey <hdp@weftsoar.net>
=item *
Chris Prather <chris@prather.org>
=item *
Matt S Trout <mst@shadowcat.co.uk>
=back
=head1 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.
=cut
|
