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Moose::Cookbook::LegacUseraCMoose::Cookbook::Legacy::Table_ClassMetaclass(3pm)

NAME
       Moose::Cookbook::Legacy::Table_ClassMetaclass - Adding a "table"
       attribute to the metaclass

VERSION
       version 2.2200

SYNOPSIS
         package MyApp::Meta::Class;
         use Moose;
         extends 'Moose::Meta::Class';

         has table => (
             is  => 'rw',
             isa => 'Str',
         );

DESCRIPTION
       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.

THE METACLASS
       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
       named "MyApp::User", 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
             if MyApp::User->meta->isa('MyApp::Meta::Class');

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.

SEE ALSO
       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

AUTHORS
       o   Stevan Little <stevan AT cpan.org>

       o   Dave Rolsky <autarch AT urth.org>

       o   Jesse Luehrs <doy AT cpan.org>

       o   Shawn M Moore <sartak AT cpan.org>

       o    ' (Yuval Kogman) <nothingmuch AT woobling.org>

       o   Karen Etheridge <ether AT cpan.org>

       o   Florian Ragwitz <rafl AT debian.org>

       o   Hans Dieter Pearcey <hdp AT cpan.org>

       o   Chris Prather <chris AT prather.org>

       o   Matt S Trout <mstrout AT cpan.org>

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.

perl v5.34.0                Moose::Cookbook::Legacy::Table_ClassMetaclass(3pm)