1Moose::Cookbook::LegacyU:s:eTrabCloen_tMCrolioabssuest:Me:edCtoaPoceklrbalososDk(o:3c:)uLmeegnatcayt:i:oTnable_ClassMetaclass(3)
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NAME

6       Moose::Cookbook::Legacy::Table_ClassMetaclass - Adding a "table"
7       attribute to the metaclass
8

VERSION

10       version 2.2015
11

SYNOPSIS

13         package MyApp::Meta::Class;
14         use Moose;
15         extends 'Moose::Meta::Class';
16
17         has table => (
18             is  => 'rw',
19             isa => 'Str',
20         );
21

DESCRIPTION

23       WARNING: Subclassing metaclasses (as opposed to providing metaclass
24       traits) is strongly discouraged. This recipe is provided solely for
25       reference when encountering older code that does this.
26
27       In this recipe, we'll create a new metaclass which has a "table"
28       attribute. This metaclass is for classes associated with a DBMS table,
29       as one might do for an ORM.
30
31       In this example, the table name is just a string, but in a real ORM the
32       table might be an object describing the table.
33

THE METACLASS

35       This really is as simple as the recipe "SYNOPSIS" shows. The trick is
36       getting your classes to use this metaclass, and providing some sort of
37       sugar for declaring the table. This is covered in
38       Moose::Cookbook::Extending::Recipe2, which shows how to make a module
39       like "Moose.pm" itself, with sugar like "has_table()".
40
41   Using this Metaclass in Practice
42       Accessing this new "table" attribute is quite simple. Given a class
43       named "MyApp::User", we could simply write the following:
44
45         my $table = MyApp::User->meta->table;
46
47       As long as "MyApp::User" has arranged to use "MyApp::Meta::Class" as
48       its metaclass, this method call just works. If we want to be more
49       careful, we can check the metaclass's class:
50
51         $table = MyApp::User->meta->table
52             if MyApp::User->meta->isa('MyApp::Meta::Class');
53

CONCLUSION

55       Creating custom metaclass is trivial. Using it is a little harder, and
56       is covered in other recipes. We will also talk about applying traits to
57       a class metaclass, which is a more flexible and cooperative
58       implementation.
59

SEE ALSO

61       Moose::Cookbook::Meta::Recipe5 - The "table" attribute implemented as a
62       metaclass trait
63
64       Moose::Cookbook::Extending::Recipe2 - Acting like Moose.pm and
65       providing sugar Moose-style
66

AUTHORS

68       •   Stevan Little <stevan@cpan.org>
69
70       •   Dave Rolsky <autarch@urth.org>
71
72       •   Jesse Luehrs <doy@cpan.org>
73
74       •   Shawn M Moore <sartak@cpan.org>
75
76       •   יובל קוג'מן (Yuval Kogman) <nothingmuch@woobling.org>
77
78       •   Karen Etheridge <ether@cpan.org>
79
80       •   Florian Ragwitz <rafl@debian.org>
81
82       •   Hans Dieter Pearcey <hdp@cpan.org>
83
84       •   Chris Prather <chris@prather.org>
85
86       •   Matt S Trout <mstrout@cpan.org>
87

89       This software is copyright (c) 2006 by Infinity Interactive, Inc.
90
91       This is free software; you can redistribute it and/or modify it under
92       the same terms as the Perl 5 programming language system itself.
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96perl v5.34.0                  Moos2e0:2:1C-o0o7k-b2o2ok::Legacy::Table_ClassMetaclass(3)
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