# NAME

Joose.Manual.MetaRoles - Yet another special kind of Roles in Joose.

# WHAT IS A META-ROLE?

Meta-role is a usual role, applied to a meta-class instance. Because of that, meta-role is also a trait.

Like any other Role, meta-role modifies the class, adding some re-usable behavior to it. Most probably this behaviour will be related to the constructing of the class being modified, for example it will provide additional builders for class.

# APPLYING META-ROLE

Meta roles can be added to class using the `metaRole` or `trait` builders:

        Class('Person', {

            trait : JooseX.Storable,

            has : {
                firstName : {},
                lastName  : {}
            }
        })

Here we declared a class `Person`, which metaclass instance (`Person.meta`) will have trait `JooseX.Storable` applied.

This trait probably provides the facilities to serialize the current state of the class and later restore it.

See this Cookbook recipe on how to create custom meta-role.

# REMOVING META-ROLE

For symmetry, its possible to remove the meta-role, using `removeMetaRole` builder:

        Person.meta.extend({
            removeMetaRole : JooseX.Storable
        })

# AUTHOR

Nickolay Platonov nickolay8@gmail.com

Heavily based on the original content of Moose::Manual, by Dave Rolsky autarch@urth.org

# COPYRIGHT AND LICENSE

Copyright (c) 2008-2011, Malte Ubl, Nickolay Platonov

All rights reserved.

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

- Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
- Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
- Neither the name of Malte Ubl nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.

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