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NAME

MooseX::NonMoose - easy subclassing of non-Moose classes

VERSION

version 0.26

SYNOPSIS

package Term::VT102::NBased;
use Moose;
use MooseX::NonMoose;
extends 'Term::VT102';

has [qw/x_base y_base/] => (
    is      => 'ro',
    isa     => 'Int',
    default => 1,
);

around x => sub {
    my $orig = shift;
    my $self = shift;
    $self->$orig(@_) + $self->x_base - 1;
};

# ... (wrap other methods)

no Moose;
# no need to fiddle with inline_constructor here
__PACKAGE__->meta->make_immutable;

my $vt = Term::VT102::NBased->new(x_base => 0, y_base => 0);

DESCRIPTION

MooseX::NonMoose allows for easily subclassing non-Moose classes with Moose, taking care of the annoying details connected with doing this, such as setting up proper inheritance from Moose::Object and installing (and inlining, at make_immutable time) a constructor that makes sure things like BUILD methods are called. It tries to be as non-intrusive as possible - when this module is used, inheriting from non-Moose classes and inheriting from Moose classes should work identically, aside from the few caveats mentioned below. One of the goals of this module is that including it in a Moose::Exporter-based package used across an entire application should be possible, without interfering with classes that only inherit from Moose modules, or even classes that don't inherit from anything at all.

There are several ways to use this module. The most straightforward is to just use MooseX::NonMoose; in your class; this should set up everything necessary for extending non-Moose modules. MooseX::NonMoose::Meta::Role::Class and MooseX::NonMoose::Meta::Role::Constructor can also be applied to your metaclasses manually, either by passing a -traits option to your use Moose; line, or by applying them using Moose::Util::MetaRole in a Moose::Exporter-based package. MooseX::NonMoose::Meta::Role::Class is the part that provides the main functionality of this module; if you don't care about inlining, this is all you need to worry about. Applying MooseX::NonMoose::Meta::Role::Constructor as well will provide an inlined constructor when you immutabilize your class.

MooseX::NonMoose allows you to manipulate the argument list that gets passed to the superclass constructor by defining a FOREIGNBUILDARGS method. This is called with the same argument list as the BUILDARGS method, but should return a list of arguments to pass to the superclass constructor. This allows MooseX::NonMoose to support superclasses whose constructors would get confused by the extra arguments that Moose requires (for attributes, etc.)

Not all non-Moose classes use new as the name of their constructor. This module allows you to extend these classes by explicitly stating which method is the constructor, during the call to extends. The syntax looks like this:

extends 'Foo' => { -constructor_name => 'create' };

similar to how you can already pass -version in the extends call in a similar way.

BUGS/CAVEATS

  • The reference that the non-Moose class uses as its instance type must match the instance type that Moose is using. Moose's default instance type is a hashref, but other modules exist to make Moose use other instance types. MooseX::InsideOut is the most general solution - it should work with any class. For globref-based classes in particular, MooseX::GlobRef will also allow Moose to work. For more information, see the 032-moosex-insideout and 033-moosex-globref tests bundled with this dist.

  • Modifying your class' @ISA after an initial extends call will potentially cause problems if any of those new entries in the @ISA override the constructor. MooseX::NonMoose wraps the nearest new() method at the time extends is called and will not see any other new() methods in the @ISA hierarchy.

  • Completely overriding the constructor in a class using MooseX::NonMoose (i.e. using sub new { ... }) currently doesn't work, although using method modifiers on the constructor should work identically to normal Moose classes.

Please report any bugs to GitHub Issues at https://github.com/doy/moosex-nonmoose/issues.

SEE ALSO

SUPPORT

You can find this documentation for this module with the perldoc command.

perldoc MooseX::NonMoose

You can also look for information at:

AUTHOR

Jesse Luehrs <doy@tozt.net>

COPYRIGHT AND LICENSE

This software is copyright (c) 2014 by Jesse Luehrs.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.