7 use Scalar::Util 'blessed';
9 use Sub::Name 'subname';
13 our $VERSION = '0.07';
14 our $AUTHORITY = 'cpan:STEVAN';
18 use Moose::Meta::Role;
19 use Moose::Util::TypeConstraints;
22 my ( $CALLER, %METAS );
27 return $METAS{$role} if exists $METAS{$role};
29 # make a subtype for each Moose class
32 => where { $_->does($role) }
33 => optimize_as { blessed($_[0]) && $_[0]->can('does') && $_[0]->does($role) }
34 unless find_type_constraint($role);
37 if ($role->can('meta')) {
38 $meta = $role->meta();
39 (blessed($meta) && $meta->isa('Moose::Meta::Role'))
40 || confess "You already have a &meta function, but it does not return a Moose::Meta::Role";
43 $meta = Moose::Meta::Role->initialize($role);
44 $meta->Moose::Meta::Class::add_method('meta' => sub { $meta })
47 return $METAS{$role} = $meta;
53 my $meta = _find_meta();
54 return subname 'Moose::Role::extends' => sub {
55 confess "Moose::Role does not currently support 'extends'"
59 my $meta = _find_meta();
60 return subname 'Moose::Role::with' => sub (@) {
62 confess "Must specify at least one role" unless @roles;
63 Class::MOP::load_class($_) for @roles;
64 ($_->can('meta') && $_->meta->isa('Moose::Meta::Role'))
65 || confess "You can only consume roles, $_ is not a Moose role"
67 if (scalar @roles == 1) {
68 $roles[0]->meta->apply($meta);
71 Moose::Meta::Role->combine(
72 map { $_->meta } @roles
78 my $meta = _find_meta();
79 return subname 'Moose::Role::requires' => sub (@) {
80 confess "Must specify at least one method" unless @_;
81 $meta->add_required_methods(@_);
85 my $meta = _find_meta();
86 return subname 'Moose::Role::excludes' => sub (@) {
87 confess "Must specify at least one role" unless @_;
88 $meta->add_excluded_roles(@_);
92 my $meta = _find_meta();
93 return subname 'Moose::Role::has' => sub ($;%) {
94 my ($name, %options) = @_;
95 $meta->add_attribute($name, %options)
99 my $meta = _find_meta();
100 return subname 'Moose::Role::before' => sub (@&) {
102 $meta->add_before_method_modifier($_, $code) for @_;
106 my $meta = _find_meta();
107 return subname 'Moose::Role::after' => sub (@&) {
109 $meta->add_after_method_modifier($_, $code) for @_;
113 my $meta = _find_meta();
114 return subname 'Moose::Role::around' => sub (@&) {
116 $meta->add_around_method_modifier($_, $code) for @_;
122 $Moose::SUPER_SLOT{$CALLER} = \*{"${CALLER}::super"};
124 my $meta = _find_meta();
125 return subname 'Moose::Role::super' => sub {};
128 my $meta = _find_meta();
129 return subname 'Moose::Role::override' => sub ($&) {
130 my ($name, $code) = @_;
131 $meta->add_override_method_modifier($name, $code);
135 my $meta = _find_meta();
136 return subname 'Moose::Role::inner' => sub {
137 confess "Moose::Role cannot support 'inner'";
141 my $meta = _find_meta();
142 return subname 'Moose::Role::augment' => sub {
143 confess "Moose::Role cannot support 'augment'";
147 return \&Carp::confess;
150 return \&Scalar::Util::blessed;
154 my $exporter = Sub::Exporter::build_exporter({
155 exports => \%exports,
167 # we should never export to main
168 return if $CALLER eq 'main';
183 Moose::Role - The Moose Role
195 my ($self, $other) = @_;
196 !$self->equal($other);
199 # ... then in your classes
209 my ($self, $other) = @_;
210 $self->as_float == $other->as_float;
215 Role support in Moose is pretty solid at this point. However, the best
216 documentation is still the the test suite. It is fairly safe to assume
217 Perl 6 style behavior and then either refer to the test suite, or ask
218 questions on #moose if something doesn't quite do what you expect.
220 We are planning writing some more documentation in the near future, but
221 nothing is ready yet, sorry.
223 =head1 EXPORTED FUNCTIONS
225 Currently Moose::Role supports all of the functions that L<Moose> exports,
226 but differs slightly in how some items are handled (see L<CAVEATS> below
229 Moose::Role also offers two role specific keyword exports:
233 =item B<requires (@method_names)>
235 Roles can require that certain methods are implemented by any class which
238 =item B<excludes (@role_names)>
240 Roles can C<exclude> other roles, in effect saying "I can never be combined
241 with these C<@role_names>". This is a feature which should not be used
248 The role support now has only a few caveats. They are as follows:
254 Roles cannot use the C<extends> keyword, it will throw an exception for now.
255 The same is true of the C<augment> and C<inner> keywords (not sure those
256 really make sense for roles). All other Moose keywords will be I<deferred>
257 so that they can be applied to the consuming class.
261 Role composition does it's best to B<not> be order sensitive when it comes
262 to conflict resolution and requirements detection. However, it is order
263 sensitive when it comes to method modifiers. All before/around/after modifiers
264 are included whenever a role is composed into a class, and then are applied
265 in the order the roles are used. This too means that there is no conflict for
266 before/around/after modifiers as well.
268 In most cases, this will be a non issue, however it is something to keep in
269 mind when using method modifiers in a role. You should never assume any
274 The C<requires> keyword currently only works with actual methods. A method
275 modifier (before/around/after and override) will not count as a fufillment
276 of the requirement, and neither will an autogenerated accessor for an attribute.
278 It is likely that the attribute accessors will eventually be allowed to fufill
279 those requirements, either that or we will introduce a C<requires_attr> keyword
280 of some kind instead. This descision has not yet been finalized.
286 All complex software has bugs lurking in it, and this module is no
287 exception. If you find a bug please either email me, or add the bug
292 Stevan Little E<lt>stevan@iinteractive.comE<gt>
294 Christian Hansen E<lt>chansen@cpan.orgE<gt>
296 =head1 COPYRIGHT AND LICENSE
298 Copyright 2006, 2007 by Infinity Interactive, Inc.
300 L<http://www.iinteractive.com>
302 This library is free software; you can redistribute it and/or modify
303 it under the same terms as Perl itself.