moosex::role::parameterized::meta::role::parameterizable(3) [osx man page]
MooseX::Role::Parameterized::Meta::Role::ParameterizableUser Contributed Perl DocumentaMooseX::Role::Parameterized::Meta::Role::Parameterizable(3) NAME
MooseX::Role::Parameterized::Meta::Role::Parameterizable - metaclass for parameterizable roles DESCRIPTION
This is the metaclass for parameterizable roles, roles that have their parameters currently unbound. These are the roles that you use "with" in Moose, but instead of composing the parameterizable role, we construct a new parameterized role (MooseX::Role::Parameterized::Meta::Role::Parameterized) and use that new parameterized instead. ATTRIBUTES
parameterized_role_metaclass The name of the class that will be used to construct the parameterized role. parameters_class The name of the class that will be used to construct the parameters object. parameters_metaclass A metaclass representing this roles's parameters. It will be an anonymous subclass of "parameters_class". Each call to "parameter" in MooseX::Role::Parameters adds an attribute to this metaclass. When this role is consumed, the parameters object will be instantiated using this metaclass. role_generator A code reference that is used to generate a role based on the parameters provided by the consumer. The user usually specifies it using the "role" in MooseX::Role::Parameterized keyword. METHODS
add_parameter $name, %options Delegates to "add_attribute" in Moose::Meta::Class on the "parameters_metaclass" object. construct_parameters %arguments Creates a new MooseX::Role::Parameterized::Parameters object using metaclass "parameters_metaclass". The arguments are those specified by the consumer as parameter values. generate_role %arguments This method generates and returns a new instance of "parameterized_role_metaclass". It can take any combination of three named parameters: arguments A hashref of parameters for the role, same as would be passed in at a "with" statement. package A package name that, if present, we will use for the generated role; if not, we generate an anonymous role. consumer A consumer metaobject, if available. apply Overrides "apply" in Moose::Meta::Role to automatically generate the parameterized role. perl v5.16.2 2012-01-12 MooseX::Role::Parameterized::Meta::Role::Parameterizable(3)
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MooseX::Role::Parameterized(3) User Contributed Perl Documentation MooseX::Role::Parameterized(3) NAME
MooseX::Role::Parameterized - roles with composition parameters SYNOPSIS
package Counter; use MooseX::Role::Parameterized; parameter name => ( isa => 'Str', required => 1, ); role { my $p = shift; my $name = $p->name; has $name => ( is => 'rw', isa => 'Int', default => 0, ); method "increment_$name" => sub { my $self = shift; $self->$name($self->$name + 1); }; method "reset_$name" => sub { my $self = shift; $self->$name(0); }; }; package MyGame::Weapon; use Moose; with Counter => { name => 'enchantment' }; package MyGame::Wand; use Moose; with Counter => { name => 'zapped' }; MooseX::Role::Parameterized::Tutorial Stop! If you're new here, please read MooseX::Role::Parameterized::Tutorial for a much gentler introduction. DESCRIPTION
Your parameterized role consists of two new things: parameter declarations and a "role" block. Parameters are declared using the "parameter" keyword which very much resembles "has" in Moose. You can use any option that "has" in Moose accepts. The default value for the "is" option is "ro" as that's a very common case. Use "is => 'bare'" if you want no accessor. These parameters will get their values when the consuming class (or role) uses "with" in Moose. A parameter object will be constructed with these values, and passed to the "role" block. The "role" block then uses the usual Moose::Role keywords to build up a role. You can shift off the parameter object to inspect what the consuming class provided as parameters. You use the parameters to customize your role however you wish. There are many possible implementations for parameterized roles (hopefully with a consistent enough API); I believe this to be the easiest and most flexible design. Coincidentally, Pugs originally had an eerily similar design. See MooseX::Role::Parameterized::Extending for some tips on how to extend this module. Why a parameters object? I've been asked several times "Why use a parameter object and not just a parameter hashref? That would eliminate the need to explicitly declare your parameters." The benefits of using an object are similar to the benefits of using Moose. You get an easy way to specify lazy defaults, type constraint, delegation, and so on. You get to use MooseX modules. You also get the usual introspective and intercessory abilities that come standard with the metaobject protocol. Ambitious users should be able to add traits to the parameters metaclass to further customize behavior. Please let me know if you're doing anything viciously complicated with this extension. :) CAVEATS
You must use this syntax to declare methods in the role block: "method NAME => sub { ... };". This is due to a limitation in Perl. In return though you can use parameters in your methods! AUTHOR
Shawn M Moore, "sartak@gmail.com" SEE ALSO
<http://sartak.org/2009/01/parametric-roles-in-perl-5.html> <http://sartak.org/2009/05/the-design-of-parameterized-roles.html> <http://stevan-little.blogspot.com/2009/07/thoughts-on-parameterized-roles.html> <http://perldition.org/articles/Parameterized%20Roles%20with%20MooseX::Declare.pod> <http://www.modernperlbooks.com/mt/2011/01/the-parametric-role-of-my-mvc-plugin-system.html> <http://jjnapiorkowski.typepad.com/modern-perl/2010/08/parameterized-roles-and-method-traits-redo.html> <http://sartak.org/talks/yapc-asia-2009/(parameterized)-roles/> <https://github.com/SamuraiJack/JooseX-Role-Parameterized> - this extension ported to JavaScript's Joose COPYRIGHT AND LICENSE
Copyright 2007-2010 Infinity Interactive This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. perl v5.18.2 2013-09-11 MooseX::Role::Parameterized(3)