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Moose::Cookbook::Meta::WhyMeta(3)    User Contributed Perl Documentation   Moose::Cookbook::Meta::WhyMeta(3)



NAME
       Moose::Cookbook::Meta::WhyMeta - Welcome to the meta world (Why Go Meta?)

VERSION
       version 2.0604

SUMMARY
       You might want to read Moose::Manual::MOP if you haven't done so yet.

       If you've ever thought "Moose is great, but I wish it did X differently", then you've gone meta. The
       meta recipes demonstrate how to change and extend the way Moose works by extending and overriding how
       the meta classes (Moose::Meta::Class, Moose::Meta::Attribute, etc) work.

       The metaclass API is a set of classes that describe classes, roles, attributes, etc. The metaclass
       API lets you ask questions about a class, like "what attributes does it have?", or "what roles does
       the class do?"

       The metaclass system also lets you make changes to a class, for example by adding new methods or
       attributes.

       The interface presented by Moose.pm ("has", "with", "extends") is just a thin layer of syntactic
       sugar over the underlying metaclass system.

       By extending and changing how this metaclass system works, you can create your own Moose variant.

   Examples
       Let's say that you want to add additional properties to attributes. Specifically, we want to add a
       "label" property to each attribute, so we can write
       "My::Class->meta()->get_attribute('size')->label()". The first recipe shows how to do this using an
       attribute trait.

       You might also want to add additional properties to your metaclass. For example, if you were writing
       an ORM based on Moose, you could associate a table name with each class via the class's metaclass
       object, letting you write "My::Class->meta()->table_name()".

SEE ALSO
       Many of the MooseX modules on CPAN implement metaclass extensions. A couple good examples include
       MooseX::Aliases and MooseX::UndefTolerant. For a more complex example see Fey::ORM or
       Bread::Board::Declare.

AUTHOR
       Moose is maintained by the Moose Cabal, along with the help of many contributors. See "CABAL" in
       Moose and "CONTRIBUTORS" in Moose for details.

COPYRIGHT AND LICENSE
       This software is copyright (c) 2012 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 v5.16.2                                     2012-09-19                Moose::Cookbook::Meta::WhyMeta(3)