s/constraint/coercion/

[gitmo/Moose.git] / lib / Moose / Cookbook.pod

=pod

=head1 NAME

Moose::Cookbook - How to cook a Moose

=head1 DESCRIPTION

The Moose cookbook is a series of recipes showing various Moose
features. Most recipes present some code demonstrating some feature,
and then explain the details of the code.

You should probably read the L<Moose::Manual> first. The manual
explains Moose concepts without being too code-heavy.

=head1 RECIPES

=head2 Basic Moose

These recipes will give you a good idea of what Moose is capable,
starting with simple attribute declaration, and moving on to more
powerful features like laziness, types, type coercion, method
modifiers, and more.

=over 4

=item L<Moose::Cookbook::Basics::Recipe1> - The (always classic) B<Point> example

A simple Moose-based class. Demonstrated Moose attributes and subclassing.

=item L<Moose::Cookbook::Basics::Recipe2> - A simple B<BankAccount> example

A slightly more complex Moose class. Demonstrates using a method
modifier in a subclass.

=item L<Moose::Cookbook::Basics::Recipe3> - A lazy B<BinaryTree> example

Demonstrates several attribute features, including types, weak
references, predicates ("does this object have a foo?"), defaults,
laziness, and triggers.

=item L<Moose::Cookbook::Basics::Recipe4> - Subtypes, and modeling a simple B<Company> class hierarchy

Introduces the creation and use of custom types, a C<BUILD> method,
and the use of C<override> in a subclass.

=item L<Moose::Cookbook::Basics::Recipe5> - More subtypes, coercion in a B<Request> class

More type examples, including the use of type coercions.

=item L<Moose::Cookbook::Basics::Recipe6> - The augment/inner example

Demonstrates the use of C<augment> method modifiers, a way of turning
the usual method overriding style "inside-out".

=item L<Moose::Cookbook::Basics::Recipe7> - Making Moose fast with immutable

Making a class immutable greatly increases the speed of accessors and
object construction.

=item L<Moose::Cookbook::Basics::Recipe8> - Managing complex relations with trigger (TODO)

I<abstract goes here>

Work off of this http://code2.0beta.co.uk/moose/svn/Moose/trunk/t/200_examples/007_Child_Parent_attr_inherit.t

=item L<Moose::Cookbook::Basics::Recipe9> - Builder methods and lazy_build

The builder feature provides an inheritable and role-composable way to
provide a default attribute value.

=item L<Moose::Cookbook::Basics::Recipe10> - Operator overloading, subtypes, and coercion

Demonstrates using operator overloading, coercion, and subtypes to
model how eye color is determined during reproduction.

=item L<Moose::Cookbook::Basics::Recipe11> - Using BUILDARGS and BUILD to hook into object construction

This recipe demonstrates the use of C<BUILDARGS> and C<BUILD> to hook
into object construction.

=back

=head2 Moose Roles

These recipes will show you how to use Moose roles.

=over 4

=item L<Moose::Cookbook::Roles::Recipe1> - The Moose::Role example

Demonstrates roles, which are also sometimes known as traits or
mix-ins. Roles provide a method of code re-use which is orthogonal to
subclassing.

=item L<Moose::Cookbook::Roles::Recipe2> - Advanced Role Composition - method exclusion and aliasing

Sometimes you just want to include part of a role in your
class. Sometimes you want the whole role but one if its methods
conflicts with one in your class. With method exclusion and aliasing,
you can work around these problems.

=item L<Moose::Cookbook::Roles::Recipe3> - Applying a role to an object instance

In this recipe, we apply a role to an existing object instance.

=back

=head2 Meta Moose

These recipes show you how to write your own meta classes, which lets
you extend the object system provide by Moose.

=over 4

=item L<Moose::Cookbook::Meta::Recipe1> - Welcome to the meta-world (Why Go Meta?)

If you're wondering what all this "meta" stuff is, and why you should
care about it, read this "recipe".

=item L<Moose::Cookbook::Meta::Recipe2> - A meta-attribute, attributes with labels

One way to extend Moose is to provide your own attribute
metaclasses. Attribute metaclasses let you extend attribute
declarations (with C<has>) and behavior to provide additional
attribute functionality.

=item L<Moose::Cookbook::Meta::Recipe3> - Labels implemented via attribute traits

Extending Moose's attribute metaclass is a great way to add
functionality. However, attributes can only have one metaclass.
Applying roles to the attribute metaclass lets you provide
composable attribute functionality.

=item L<Moose::Cookbook::Meta::Recipe4> - Adding a "table" attribute to the metaclass

If you want to store more information about your classes, you'll have
to extend C<Moose::Meta::Class>. Doing so is simple, but you'll
probably also want to provide some sugar, so see
L<Moose::Cookbook::Extending::Recipe2> as well.

=item L<Moose::Cookbook::Meta::Recipe5> - The "table" attribute implemented as a metaclass trait

This example takes the class metaclass we saw in the previous recipe
and reimplements it as a metaclass trait.

=item L<Moose::Cookbook::Meta::Recipe6> - Hooking into the immutabilization system (TODO)

Moose has a feature known as "immutabilization". By calling C<<
__PACKAGE__->meta()->make_immutable() >> after defining your class
(attributes, roles, etc), you tell Moose to optimize things like
object creation, attribute access, and so on.

If you are creating your own metaclasses, you may need to hook into
the immutabilization system. This cuts across a number of spots,
including the metaclass class, meta method classes, and possibly the
meta-instance class as well.

This recipe shows you how to write extensions which immutabilize
properly.

=item L<Moose::Cookbook::Meta::Recipe7> - Using a blessed array reference as an object instance

This recipe shows an example of how you create your own meta-instance
class. The meta-instance determines the internal structure of object
instances and provide access to attribute slots.

=back

=head2 Extending Moose

These recipes cover some more ways to extend Moose, and will be useful
if you plan to write your own C<MooseX> module.

=over 4

=item L<Moose::Cookbook::Extending::Recipe1> - Moose extension overview

There are quite a number of ways to extend Moose. This recipe explains
provides an overview of each method, and provides recommendations for
when each is appropriate.

=item L<Moose::Cookbook::Extending::Recipe2> - Providing a base object class role

Many base object class extensions can be implemented as roles. This
example shows how to provide a base object class debugging role that
is applied to any class that uses a notional C<MooseX::Debugging>
module.

=item L<Moose::Cookbook::Extending::Recipe3> - Providing an alternate base object class

You may find that you want to provide an alternate base object class
along with a meta extension, or maybe you just want to add some
functionality to all your classes without typing C<extends
'MyApp::Base'> over and over.

=item L<Moose::Cookbook::Extending::Recipe4> - Acting like Moose.pm and providing sugar Moose-style

This recipe shows how to provide a replacement for C<Moose.pm>. You
may want to do this as part of the API for a C<MooseX> module,
especially if you want to default to a new metaclass class or base
object class.

=back

=head1 SNACKS

=over 4

=item L<Moose::Cookbook::Snack::Keywords>

=item L<Moose::Cookbook::Snack::Types>

=back

=head1 SEE ALSO

=over 4

=item L<http://www.gsph.com/index.php?Lang=En&ID=291>

=back

=head1 AUTHOR

Stevan Little E<lt>stevan@iinteractive.comE<gt>

=head1 COPYRIGHT AND LICENSE

Copyright 2006-2009 by Infinity Interactive, Inc.

L<http://www.iinteractive.com>

This library is free software; you can redistribute it and/or modify
it under the same terms as Perl itself.

=cut