7 use Scalar::Util 'blessed';
8 use Carp 'confess', 'croak';
13 our $VERSION = '0.55_02';
14 $VERSION = eval $VERSION;
15 our $AUTHORITY = 'cpan:STEVAN';
20 use Moose::Meta::Role;
21 use Moose::Util::TypeConstraints;
24 croak "Roles do not currently support 'extends'";
28 Moose::Util::apply_all_roles( Moose::Meta::Role->initialize(shift), @_ );
32 my $meta = Moose::Meta::Role->initialize(shift);
33 croak "Must specify at least one method" unless @_;
34 $meta->add_required_methods(@_);
38 my $meta = Moose::Meta::Role->initialize(shift);
39 croak "Must specify at least one role" unless @_;
40 $meta->add_excluded_roles(@_);
44 my $meta = Moose::Meta::Role->initialize(shift);
46 croak 'Usage: has \'name\' => ( key => value, ... )' if @_ == 1;
48 my $attrs = ( ref($name) eq 'ARRAY' ) ? $name : [ ($name) ];
49 $meta->add_attribute( $_, %options ) for @$attrs;
53 my $meta = Moose::Meta::Role->initialize(shift);
57 croak "Moose::Role do not currently support "
59 . " references for before method modifiers"
61 $meta->add_before_method_modifier( $_, $code );
66 my $meta = Moose::Meta::Role->initialize(shift);
70 croak "Moose::Role do not currently support "
72 . " references for after method modifiers"
74 $meta->add_after_method_modifier( $_, $code );
79 my $meta = Moose::Meta::Role->initialize(shift);
82 croak "Moose::Role do not currently support "
84 . " references for around method modifiers"
86 $meta->add_around_method_modifier( $_, $code );
90 # see Moose.pm for discussion
92 return unless $Moose::SUPER_BODY;
93 $Moose::SUPER_BODY->(@Moose::SUPER_ARGS);
97 my $meta = Moose::Meta::Role->initialize(shift);
98 my ( $name, $code ) = @_;
99 $meta->add_override_method_modifier( $name, $code );
103 croak "Moose::Role cannot support 'inner'";
107 croak "Moose::Role cannot support 'augment'";
110 my $exporter = Moose::Exporter->setup_import_methods(
112 qw( with requires excludes has before after around override make_immutable )
115 qw( extends super inner augment ),
117 \&Scalar::Util::blessed,
125 my $role = $args{for_class}
127 "Cannot call init_meta without specifying a for_class";
129 my $metaclass = $args{metaclass} || "Moose::Meta::Role";
131 # make a subtype for each Moose class
132 role_type $role unless find_type_constraint($role);
134 # FIXME copy from Moose.pm
136 if ($role->can('meta')) {
137 $meta = $role->meta();
138 (blessed($meta) && $meta->isa('Moose::Meta::Role'))
139 || confess "You already have a &meta function, but it does not return a Moose::Meta::Role";
142 $meta = $metaclass->initialize($role);
143 $meta->alias_method('meta' => sub { $meta });
157 Moose::Role - The Moose Role
162 use Moose::Role; # automatically turns on strict and warnings
167 my ($self, $other) = @_;
168 !$self->equal($other);
171 # ... then in your classes
174 use Moose; # automatically turns on strict and warnings
179 my ($self, $other) = @_;
180 $self->as_float == $other->as_float;
185 Role support in Moose is pretty solid at this point. However, the best
186 documentation is still the the test suite. It is fairly safe to assume Perl 6
187 style behavior and then either refer to the test suite, or ask questions on
188 #moose if something doesn't quite do what you expect.
190 We are planning writing some more documentation in the near future, but nothing
193 =head1 EXPORTED FUNCTIONS
195 Moose::Role currently supports all of the functions that L<Moose> exports, but
196 differs slightly in how some items are handled (see L<CAVEATS> below for
199 Moose::Role also offers two role-specific keyword exports:
203 =item B<requires (@method_names)>
205 Roles can require that certain methods are implemented by any class which
208 =item B<excludes (@role_names)>
210 Roles can C<exclude> other roles, in effect saying "I can never be combined
211 with these C<@role_names>". This is a feature which should not be used
218 Moose::Role offers a way to remove the keywords it exports, through the
219 C<unimport> method. You simply have to say C<no Moose::Role> at the bottom of
220 your code for this to work.
222 =head2 B<< Moose::Role->init_meta(for_class => $role, metaclass => $metaclass) >>
224 The C<init_meta> method sets up the metaclass object for the role
225 specified by C<for_class>. It also injects a a C<meta> accessor into
226 the role so you can get at this object.
228 The default metaclass is L<Moose::Meta::Role>. You can specify an
229 alternate metaclass with the C<metaclass> parameter.
233 Role support has only a few caveats:
239 Roles cannot use the C<extends> keyword; it will throw an exception for now.
240 The same is true of the C<augment> and C<inner> keywords (not sure those
241 really make sense for roles). All other Moose keywords will be I<deferred>
242 so that they can be applied to the consuming class.
246 Role composition does its best to B<not> be order-sensitive when it comes to
247 conflict resolution and requirements detection. However, it is order-sensitive
248 when it comes to method modifiers. All before/around/after modifiers are
249 included whenever a role is composed into a class, and then applied in the order
250 in which the roles are used. This also means that there is no conflict for
251 before/around/after modifiers.
253 In most cases, this will be a non-issue; however, it is something to keep in
254 mind when using method modifiers in a role. You should never assume any
259 The C<requires> keyword currently only works with actual methods. A method
260 modifier (before/around/after and override) will not count as a fufillment
261 of the requirement, and neither will an autogenerated accessor for an attribute.
263 It is likely that attribute accessors will eventually be allowed to fufill those
264 requirements, or we will introduce a C<requires_attr> keyword of some kind
265 instead. This decision has not yet been finalized.
271 All complex software has bugs lurking in it, and this module is no
272 exception. If you find a bug please either email me, or add the bug
277 Stevan Little E<lt>stevan@iinteractive.comE<gt>
279 Christian Hansen E<lt>chansen@cpan.orgE<gt>
281 =head1 COPYRIGHT AND LICENSE
283 Copyright 2006-2008 by Infinity Interactive, Inc.
285 L<http://www.iinteractive.com>
287 This library is free software; you can redistribute it and/or modify
288 it under the same terms as Perl itself.