2 package Moose::Meta::Role;
9 use Scalar::Util 'blessed';
10 use B 'svref_2object';
12 use Moose::Meta::Class;
14 our $VERSION = '0.04';
18 ## the meta for the role package
20 __PACKAGE__->meta->add_attribute('_role_meta' => (
21 reader => '_role_meta',
22 init_arg => ':role_meta'
27 __PACKAGE__->meta->add_attribute('roles' => (
28 reader => 'get_roles',
34 __PACKAGE__->meta->add_attribute('excluded_roles_map' => (
35 reader => 'get_excluded_roles_map',
41 __PACKAGE__->meta->add_attribute('attribute_map' => (
42 reader => 'get_attribute_map',
48 __PACKAGE__->meta->add_attribute('required_methods' => (
49 reader => 'get_required_methods_map',
55 __PACKAGE__->meta->add_attribute('before_method_modifiers' => (
56 reader => 'get_before_method_modifiers_map',
57 default => sub { {} } # (<name> => [ (CODE) ])
60 __PACKAGE__->meta->add_attribute('after_method_modifiers' => (
61 reader => 'get_after_method_modifiers_map',
62 default => sub { {} } # (<name> => [ (CODE) ])
65 __PACKAGE__->meta->add_attribute('around_method_modifiers' => (
66 reader => 'get_around_method_modifiers_map',
67 default => sub { {} } # (<name> => [ (CODE) ])
70 __PACKAGE__->meta->add_attribute('override_method_modifiers' => (
71 reader => 'get_override_method_modifiers_map',
72 default => sub { {} } # (<name> => CODE)
80 $options{':role_meta'} = Moose::Meta::Class->initialize(
82 ':method_metaclass' => 'Moose::Meta::Role::Method'
83 ) unless defined $options{':role_meta'} &&
84 $options{':role_meta'}->isa('Moose::Meta::Class');
85 my $self = $class->meta->new_object(%options);
92 my ($self, $role) = @_;
93 (blessed($role) && $role->isa('Moose::Meta::Role'))
94 || confess "Roles must be instances of Moose::Meta::Role";
95 push @{$self->get_roles} => $role;
98 sub calculate_all_roles {
101 grep { !$seen{$_->name}++ } $self, map { $_->calculate_all_roles } @{ $self->get_roles };
105 my ($self, $role_name) = @_;
107 || confess "You must supply a role name to look for";
108 # if we are it,.. then return true
109 return 1 if $role_name eq $self->name;
110 # otherwise.. check our children
111 foreach my $role (@{$self->get_roles}) {
112 return 1 if $role->does_role($role_name);
119 sub add_excluded_roles {
120 my ($self, @excluded_role_names) = @_;
121 $self->get_excluded_roles_map->{$_} = undef foreach @excluded_role_names;
124 sub get_excluded_roles_list {
126 keys %{$self->get_excluded_roles_map};
130 my ($self, $role_name) = @_;
131 exists $self->get_excluded_roles_map->{$role_name} ? 1 : 0;
136 sub add_required_methods {
137 my ($self, @methods) = @_;
138 $self->get_required_methods_map->{$_} = undef foreach @methods;
141 sub remove_required_methods {
142 my ($self, @methods) = @_;
143 delete $self->get_required_methods_map->{$_} foreach @methods;
146 sub get_required_method_list {
148 keys %{$self->get_required_methods_map};
151 sub requires_method {
152 my ($self, $method_name) = @_;
153 exists $self->get_required_methods_map->{$method_name} ? 1 : 0;
156 sub _clean_up_required_methods {
158 foreach my $method ($self->get_required_method_list) {
159 $self->remove_required_methods($method)
160 if $self->has_method($method);
167 # we delegate to some role_meta methods for convience here
168 # the Moose::Meta::Role is meant to be a read-only interface
169 # to the underlying role package, if you want to manipulate
170 # that, just use ->role_meta
172 sub name { (shift)->_role_meta->name }
173 sub version { (shift)->_role_meta->version }
175 sub get_method { (shift)->_role_meta->get_method(@_) }
176 sub has_method { (shift)->_role_meta->has_method(@_) }
177 sub alias_method { (shift)->_role_meta->alias_method(@_) }
178 sub get_method_list {
182 # this is a kludge for now,... these functions
183 # should not be showing up in the list at all,
184 # but they do, so we need to switch Moose::Role
185 # and Moose to use Sub::Exporter to prevent this
186 !/^(meta|has|extends|blessed|confess|augment|inner|override|super|before|after|around|with|requires)$/
187 } $self->_role_meta->get_method_list;
190 # ... however the items in statis (attributes & method modifiers)
191 # can be removed and added to through this API
199 if (scalar @_ == 1 && ref($_[0]) eq 'HASH') {
205 $self->get_attribute_map->{$name} = $attr_desc;
209 my ($self, $name) = @_;
210 exists $self->get_attribute_map->{$name} ? 1 : 0;
214 my ($self, $name) = @_;
215 $self->get_attribute_map->{$name}
218 sub remove_attribute {
219 my ($self, $name) = @_;
220 delete $self->get_attribute_map->{$name}
223 sub get_attribute_list {
225 keys %{$self->get_attribute_map};
229 ## applying a role to a class ...
231 sub _check_excluded_roles {
232 my ($self, $other) = @_;
233 if ($other->excludes_role($self->name)) {
234 confess "Conflict detected: " . $other->name . " excludes role '" . $self->name . "'";
236 foreach my $excluded_role_name ($self->get_excluded_roles_list) {
237 if ($other->does_role($excluded_role_name)) {
238 confess "The class " . $other->name . " does the excluded role '$excluded_role_name'";
241 if ($other->isa('Moose::Meta::Role')) {
242 $other->add_excluded_roles($excluded_role_name);
244 # else -> ignore it :)
249 sub _check_required_methods {
250 my ($self, $other) = @_;
252 # we might need to move this down below the
253 # the attributes so that we can require any
254 # attribute accessors. However I am thinking
255 # that maybe those are somehow exempt from
256 # the require methods stuff.
257 foreach my $required_method_name ($self->get_required_method_list) {
260 # This should not call has_method, instead it should
261 # call find_method_by_name (to be added to Class::MOP)
262 unless ($other->has_method($required_method_name)) {
263 if ($other->isa('Moose::Meta::Role')) {
264 $other->add_required_methods($required_method_name);
267 confess "'" . $self->name . "' requires the method '$required_method_name' " .
268 "to be implemented by '" . $other->name . "'";
273 # we need to make sure that the method is
274 # not a method modifier, because those do
275 # not satisfy the requirements ...
278 # This should also call find_method_by_name
279 my $method = $other->get_method($required_method_name);
280 # check if it is an override or a generated accessor ..
281 (!$method->isa('Moose::Meta::Method::Overriden') &&
282 !$method->isa('Class::MOP::Attribute::Accessor'))
283 || confess "'" . $self->name . "' requires the method '$required_method_name' " .
284 "to be implemented by '" . $other->name . "', the method is only a method modifier";
285 # before/after/around methods are a little trickier
286 # since we wrap the original local method (if applicable)
287 # so we need to check if the original wrapped method is
288 # from the same package, and not a wrap of the super method
289 if ($method->isa('Class::MOP::Method::Wrapped')) {
290 ($method->get_original_method->package_name eq $other->name)
291 || confess "'" . $self->name . "' requires the method '$required_method_name' " .
292 "to be implemented by '" . $other->name . "', the method is only a method modifier";
298 sub _apply_attributes {
299 my ($self, $other) = @_;
300 foreach my $attribute_name ($self->get_attribute_list) {
301 # it if it has one already
302 if ($other->has_attribute($attribute_name) &&
303 # make sure we haven't seen this one already too
304 $other->get_attribute($attribute_name) != $self->get_attribute($attribute_name)) {
305 # see if we are being composed
307 if ($other->isa('Moose::Meta::Role')) {
308 # all attribute conflicts between roles
309 # result in an immediate fatal error
310 confess "Role '" . $self->name . "' has encountered an attribute conflict " .
311 "during composition. This is fatal error and cannot be disambiguated.";
314 # but if this is a class, we
315 # can safely skip adding the
316 # attribute to the class
321 $other->add_attribute(
323 $self->get_attribute($attribute_name)
330 my ($self, $other) = @_;
331 foreach my $method_name ($self->get_method_list) {
332 # it if it has one already
333 if ($other->has_method($method_name) &&
334 # and if they are not the same thing ...
335 $other->get_method($method_name) != $self->get_method($method_name)) {
336 # see if we are composing into a role
337 if ($other->isa('Moose::Meta::Role')) {
338 # method conflicts between roles result
339 # in the method becoming a requirement
340 $other->add_required_methods($method_name);
342 # we have to remove the method from our
343 # role, if this is being called from combine()
344 # which means the meta is an anon class
345 # this *may* cause problems later, but it
346 # is probably fairly safe to assume that
347 # anon classes will only be used internally
348 # or by people who know what they are doing
349 $other->_role_meta->remove_method($method_name)
350 if $other->_role_meta->name =~ /__ANON__/;
357 # add it, although it could be overriden
358 $other->alias_method(
360 $self->get_method($method_name)
367 my ($self, $other) = @_;
369 $self->_check_excluded_roles($other);
370 $self->_check_required_methods($other);
372 $self->_apply_attributes($other);
373 $self->_apply_methods($other);
375 $other->add_role($self);
379 my ($class, @roles) = @_;
381 my $combined = $class->new(
382 ':role_meta' => Moose::Meta::Class->create_anon_class()
385 foreach my $role (@roles) {
386 $role->apply($combined);
389 $combined->_clean_up_required_methods;
394 package Moose::Meta::Role::Method;
399 our $VERSION = '0.01';
401 use base 'Class::MOP::Method';
411 Moose::Meta::Role - The Moose Role metaclass
415 Moose's Roles are being actively developed, please see L<Moose::Role>
416 for more information. For the most part, this has no user-serviceable
417 parts inside. It's API is still subject to some change (although
418 probably not that much really).
456 =item B<add_excluded_roles>
458 =item B<excludes_role>
460 =item B<get_excluded_roles_list>
462 =item B<get_excluded_roles_map>
464 =item B<calculate_all_roles>
474 =item B<alias_method>
476 =item B<get_method_list>
482 =item B<add_attribute>
484 =item B<has_attribute>
486 =item B<get_attribute>
488 =item B<get_attribute_list>
490 =item B<get_attribute_map>
492 =item B<remove_attribute>
498 =item B<add_required_methods>
500 =item B<remove_required_methods>
502 =item B<get_required_method_list>
504 =item B<get_required_methods_map>
506 =item B<requires_method>
512 =item B<add_after_method_modifier>
514 =item B<add_around_method_modifier>
516 =item B<add_before_method_modifier>
518 =item B<add_override_method_modifier>
524 =item B<has_after_method_modifiers>
526 =item B<has_around_method_modifiers>
528 =item B<has_before_method_modifiers>
530 =item B<has_override_method_modifier>
536 =item B<get_after_method_modifiers>
538 =item B<get_around_method_modifiers>
540 =item B<get_before_method_modifiers>
542 =item B<get_method_modifier_list>
548 =item B<get_override_method_modifier>
550 =item B<get_after_method_modifiers_map>
552 =item B<get_around_method_modifiers_map>
554 =item B<get_before_method_modifiers_map>
556 =item B<get_override_method_modifiers_map>
562 All complex software has bugs lurking in it, and this module is no
563 exception. If you find a bug please either email me, or add the bug
568 Stevan Little E<lt>stevan@iinteractive.comE<gt>
570 =head1 COPYRIGHT AND LICENSE
572 Copyright 2006 by Infinity Interactive, Inc.
574 L<http://www.iinteractive.com>
576 This library is free software; you can redistribute it and/or modify
577 it under the same terms as Perl itself.