2 package Moose::Meta::Class;
10 use Scalar::Util 'weaken', 'blessed';
12 our $VERSION = '0.55_02';
13 $VERSION = eval $VERSION;
14 our $AUTHORITY = 'cpan:STEVAN';
16 use Moose::Meta::Method::Overriden;
17 use Moose::Meta::Method::Augmented;
19 use base 'Class::MOP::Class';
21 __PACKAGE__->meta->add_attribute('roles' => (
26 __PACKAGE__->meta->add_attribute('constructor_class' => (
27 accessor => 'constructor_class',
28 default => sub { 'Moose::Meta::Method::Constructor' }
31 __PACKAGE__->meta->add_attribute('destructor_class' => (
32 accessor => 'destructor_class',
33 default => sub { 'Moose::Meta::Method::Destructor' }
39 return Class::MOP::get_metaclass_by_name($pkg)
40 || $class->SUPER::initialize($pkg,
41 'attribute_metaclass' => 'Moose::Meta::Attribute',
42 'method_metaclass' => 'Moose::Meta::Method',
43 'instance_metaclass' => 'Moose::Meta::Instance',
49 my ($self, $package_name, %options) = @_;
51 (ref $options{roles} eq 'ARRAY')
52 || confess "You must pass an ARRAY ref of roles"
53 if exists $options{roles};
55 my $class = $self->SUPER::create($package_name, %options);
57 if (exists $options{roles}) {
58 Moose::Util::apply_all_roles($class, @{$options{roles}});
66 sub create_anon_class {
67 my ($self, %options) = @_;
69 my $cache_ok = delete $options{cache};
71 # something like Super::Class|Super::Class::2=Role|Role::1
72 my $cache_key = join '=' => (
73 join('|', sort @{$options{superclasses} || []}),
74 join('|', sort @{$options{roles} || []}),
77 if ($cache_ok && defined $ANON_CLASSES{$cache_key}) {
78 return $ANON_CLASSES{$cache_key};
81 my $new_class = $self->SUPER::create_anon_class(%options);
83 $ANON_CLASSES{$cache_key} = $new_class
90 my ($self, $role) = @_;
91 (blessed($role) && $role->isa('Moose::Meta::Role'))
92 || confess "Roles must be instances of Moose::Meta::Role";
93 push @{$self->roles} => $role;
96 sub calculate_all_roles {
99 grep { !$seen{$_->name}++ } map { $_->calculate_all_roles } @{ $self->roles };
103 my ($self, $role_name) = @_;
105 || confess "You must supply a role name to look for";
106 foreach my $class ($self->class_precedence_list) {
107 next unless $class->can('meta') && $class->meta->can('roles');
108 foreach my $role (@{$class->meta->roles}) {
109 return 1 if $role->does_role($role_name);
116 my ($self, $role_name) = @_;
118 || confess "You must supply a role name to look for";
119 foreach my $class ($self->class_precedence_list) {
120 next unless $class->can('meta');
122 # in the pretty rare instance when a Moose metaclass
123 # is itself extended with a role, this check needs to
124 # be done since some items in the class_precedence_list
125 # might in fact be Class::MOP based still.
126 next unless $class->meta->can('roles');
127 foreach my $role (@{$class->meta->roles}) {
128 return 1 if $role->excludes_role($role_name);
136 my $params = @_ == 1 ? $_[0] : {@_};
137 my $self = $class->SUPER::new_object($params);
138 foreach my $attr ($class->compute_all_applicable_attributes()) {
139 # if we have a trigger, then ...
140 if ($attr->can('has_trigger') && $attr->has_trigger) {
141 # make sure we have an init-arg ...
142 if (defined(my $init_arg = $attr->init_arg)) {
143 # now make sure an init-arg was passes ...
144 if (exists $params->{$init_arg}) {
145 # and if get here, fire the trigger
148 # check if there is a coercion
149 ($attr->should_coerce
150 # and if so, we need to grab the
151 # value that is actually been stored
152 ? $attr->get_read_method_ref->($self)
153 # otherwise, just get the value from
154 # the constructor params
155 : $params->{$init_arg}),
165 sub construct_instance {
167 my $params = @_ == 1 ? $_[0] : {@_};
168 my $meta_instance = $class->get_meta_instance;
170 # the code below is almost certainly incorrect
171 # but this is foreign inheritence, so we might
172 # have to kludge it in the end.
173 my $instance = $params->{'__INSTANCE__'} || $meta_instance->create_instance();
174 foreach my $attr ($class->compute_all_applicable_attributes()) {
175 $attr->initialize_instance_slot($meta_instance, $instance, $params);
185 my $current = Class::MOP::check_package_cache_flag($self->name);
187 if (defined $self->{'_package_cache_flag'} && $self->{'_package_cache_flag'} == $current) {
188 return $self->{'methods'};
191 $self->{_package_cache_flag} = $current;
193 my $map = $self->{'methods'};
195 my $class_name = $self->name;
196 my $method_metaclass = $self->method_metaclass;
198 my %all_code = $self->get_all_package_symbols('CODE');
200 foreach my $symbol (keys %all_code) {
201 my $code = $all_code{$symbol};
203 next if exists $map->{$symbol} &&
204 defined $map->{$symbol} &&
205 $map->{$symbol}->body == $code;
207 my ($pkg, $name) = Class::MOP::get_code_info($code);
209 if ($pkg->can('meta')
211 # we don't know what ->meta we are calling
212 # here, so we need to be careful cause it
213 # just might blow up at us, or just complain
214 # loudly (in the case of Curses.pm) so we
215 # just be a little overly cautious here.
217 && eval { no warnings; blessed($pkg->meta) }
218 && $pkg->meta->isa('Moose::Meta::Role')) {
219 #my $role = $pkg->meta->name;
220 #next unless $self->does_role($role);
225 # in 5.10 constant.pm the constants show up
226 # as being in the right package, but in pre-5.10
227 # they show up as constant::__ANON__ so we
228 # make an exception here to be sure that things
229 # work as expected in both.
231 unless ($pkg eq 'constant' && $name eq '__ANON__') {
232 next if ($pkg || '') ne $class_name ||
233 (($name || '') ne '__ANON__' && ($pkg || '') ne $class_name);
238 $map->{$symbol} = $method_metaclass->wrap(
240 package_name => $class_name,
248 ### ---------------------------------------------
252 $self->SUPER::add_attribute(
253 (blessed $_[0] && $_[0]->isa('Class::MOP::Attribute')
255 : $self->_process_attribute(@_))
259 sub add_override_method_modifier {
260 my ($self, $name, $method, $_super_package) = @_;
262 (!$self->has_method($name))
263 || confess "Cannot add an override method if a local method is already present";
265 $self->add_method($name => Moose::Meta::Method::Overriden->new(
268 package => $_super_package, # need this for roles
273 sub add_augment_method_modifier {
274 my ($self, $name, $method) = @_;
275 (!$self->has_method($name))
276 || confess "Cannot add an augment method if a local method is already present";
278 $self->add_method($name => Moose::Meta::Method::Augmented->new(
285 ## Private Utility methods ...
287 sub _find_next_method_by_name_which_is_not_overridden {
288 my ($self, $name) = @_;
289 foreach my $method ($self->find_all_methods_by_name($name)) {
290 return $method->{code}
291 if blessed($method->{code}) && !$method->{code}->isa('Moose::Meta::Method::Overriden');
296 # Right now, this method does not handle the case where two
297 # metaclasses differ only in roles applied against a common parent
298 # class. This can happen fairly easily when ClassA applies metaclass
299 # Role1, and then a subclass, ClassB, applies a metaclass Role2. In
300 # reality, the way to resolve the problem is to apply Role1 to
301 # ClassB's metaclass. However, we cannot currently detect this, and so
302 # we simply fail to fix the incompatibility.
304 # The algorithm for fixing it is not that complicated.
306 # First, we see if the two metaclasses share a common parent (probably
307 # Moose::Meta::Class).
309 # Second, we see if the metaclasses only differ in terms of roles
310 # applied. This second point is where things break down. There is no
311 # easy way to determine if the difference is from roles only. To do
312 # that, we'd need to able to reliably determine the origin of each
313 # method and attribute in each metaclass. If all the unshared methods
314 # & attributes come from roles, and there is no name collision, then
315 # we can apply the missing roles to the child's metaclass.
317 # Tracking the origin of these things will require some fairly
318 # invasive changes to various parts of Moose & Class::MOP.
320 # For now, the workaround is for ClassB to subclass ClassA _and then_
321 # apply metaclass roles to its metaclass.
322 sub _fix_metaclass_incompatability {
323 my ($self, @superclasses) = @_;
325 foreach my $super (@superclasses) {
326 # don't bother if it does not have a meta.
327 my $super_meta = Class::MOP::Class->initialize($super) or next;
328 next unless $super_meta->isa("Class::MOP::Class");
330 # get the name, make sure we take
331 # immutable classes into account
333 = $super_meta->is_immutable
334 ? $super_meta->get_mutable_metaclass_name
338 # if our metaclass is compatible
339 $self->isa($super_meta_name)
341 # and our instance metaclass is also compatible then no
343 $self->instance_metaclass->isa( $super_meta->instance_metaclass );
345 next unless $super_meta->isa( ref($self) );
347 unless ( $self->is_pristine ) {
348 confess "Not reinitializing metaclass for "
350 . ", it isn't pristine";
353 $self = $super_meta->reinitialize(
355 attribute_metaclass => $super_meta->attribute_metaclass,
356 method_metaclass => $super_meta->method_metaclass,
357 instance_metaclass => $super_meta->instance_metaclass,
360 $self->$_( $super_meta->$_ )
361 for qw( constructor_class destructor_class );
368 # this was crap anyway, see
369 # Moose::Util::apply_all_roles
371 sub _apply_all_roles {
372 Carp::croak 'DEPRECATED: use Moose::Util::apply_all_roles($meta, @roles) instead'
375 sub _process_attribute {
376 my ( $self, $name, @args ) = @_;
378 @args = %{$args[0]} if scalar @args == 1 && ref($args[0]) eq 'HASH';
380 if ($name =~ /^\+(.*)/) {
381 return $self->_process_inherited_attribute($1, @args);
384 return $self->_process_new_attribute($name, @args);
388 sub _process_new_attribute {
389 my ( $self, $name, @args ) = @_;
391 $self->attribute_metaclass->interpolate_class_and_new($name, @args);
394 sub _process_inherited_attribute {
395 my ($self, $attr_name, %options) = @_;
396 my $inherited_attr = $self->find_attribute_by_name($attr_name);
397 (defined $inherited_attr)
398 || confess "Could not find an attribute by the name of '$attr_name' to inherit from";
399 if ($inherited_attr->isa('Moose::Meta::Attribute')) {
400 return $inherited_attr->clone_and_inherit_options(%options);
404 # kind of a kludge to handle Class::MOP::Attributes
405 return $inherited_attr->Moose::Meta::Attribute::clone_and_inherit_options(%options);
409 ## -------------------------------------------------
411 use Moose::Meta::Method::Constructor;
412 use Moose::Meta::Method::Destructor;
414 # This could be done by using SUPER and altering ->options
415 # I am keeping it this way to make it more explicit.
416 sub create_immutable_transformer {
418 my $class = Class::MOP::Immutable->new($self, {
419 read_only => [qw/superclasses/],
426 remove_package_symbol
430 class_precedence_list => 'ARRAY',
431 linearized_isa => 'ARRAY', # FIXME perl 5.10 memoizes this on its own, no need?
432 get_all_methods => 'ARRAY',
433 #get_all_attributes => 'ARRAY', # it's an alias, no need, but maybe in the future
434 compute_all_applicable_attributes => 'ARRAY',
435 get_meta_instance => 'SCALAR',
436 get_method_map => 'SCALAR',
437 calculate_all_roles => 'ARRAY',
440 # this is ugly, but so are typeglobs,
441 # so whattayahgonnadoboutit
444 add_package_symbol => sub {
445 my $original = shift;
446 confess "Cannot add package symbols to an immutable metaclass"
447 unless (caller(2))[3] eq 'Class::MOP::Package::get_package_symbol';
448 goto $original->body;
457 $self->SUPER::make_immutable
459 constructor_class => $self->constructor_class,
460 destructor_class => $self->destructor_class,
461 inline_destructor => 1,
463 # no need to do this,
464 # Moose always does it
465 inline_accessors => 0,
478 Moose::Meta::Class - The Moose metaclass
482 This is a subclass of L<Class::MOP::Class> with Moose specific
485 For the most part, the only time you will ever encounter an
486 instance of this class is if you are doing some serious deep
487 introspection. To really understand this class, you need to refer
488 to the L<Class::MOP::Class> documentation.
498 Overrides original to accept a list of roles to apply to
501 my $metaclass = Moose::Meta::Class->create( 'New::Class', roles => [...] );
503 =item B<create_anon_class>
505 Overrides original to support roles and caching.
507 my $metaclass = Moose::Meta::Class->create_anon_class(
508 superclasses => ['Foo'],
509 roles => [qw/Some Roles Go Here/],
513 =item B<make_immutable>
515 Override original to add default options for inlining destructor
516 and altering the Constructor metaclass.
518 =item B<create_immutable_transformer>
520 Override original to lock C<add_role> and memoize C<calculate_all_roles>
524 We override this method to support the C<trigger> attribute option.
526 =item B<construct_instance>
528 This provides some Moose specific extensions to this method, you
529 almost never call this method directly unless you really know what
532 This method makes sure to handle the moose weak-ref, type-constraint
533 and type coercion features.
535 =item B<get_method_map>
537 This accommodates Moose::Meta::Role::Method instances, which are
538 aliased, instead of added, but still need to be counted as valid
541 =item B<add_override_method_modifier ($name, $method)>
543 This will create an C<override> method modifier for you, and install
546 =item B<add_augment_method_modifier ($name, $method)>
548 This will create an C<augment> method modifier for you, and install
551 =item B<calculate_all_roles>
555 This will return an array of C<Moose::Meta::Role> instances which are
556 attached to this class.
558 =item B<add_role ($role)>
560 This takes an instance of C<Moose::Meta::Role> in C<$role>, and adds it
561 to the list of associated roles.
563 =item B<does_role ($role_name)>
565 This will test if this class C<does> a given C<$role_name>. It will
566 not only check it's local roles, but ask them as well in order to
567 cascade down the role hierarchy.
569 =item B<excludes_role ($role_name)>
571 This will test if this class C<excludes> a given C<$role_name>. It will
572 not only check it's local roles, but ask them as well in order to
573 cascade down the role hierarchy.
575 =item B<add_attribute ($attr_name, %params|$params)>
577 This method does the same thing as L<Class::MOP::Class::add_attribute>, but adds
578 support for taking the C<$params> as a HASH ref.
584 All complex software has bugs lurking in it, and this module is no
585 exception. If you find a bug please either email me, or add the bug
590 Stevan Little E<lt>stevan@iinteractive.comE<gt>
592 =head1 COPYRIGHT AND LICENSE
594 Copyright 2006-2008 by Infinity Interactive, Inc.
596 L<http://www.iinteractive.com>
598 This library is free software; you can redistribute it and/or modify
599 it under the same terms as Perl itself.