2 package Class::MOP::Class;
7 use Class::MOP::Immutable;
8 use Class::MOP::Instance;
9 use Class::MOP::Method::Wrapped;
12 use Scalar::Util 'blessed', 'weaken';
14 our $VERSION = '0.65';
15 $VERSION = eval $VERSION;
16 our $AUTHORITY = 'cpan:STEVAN';
18 use base 'Class::MOP::Module';
28 $package_name = shift;
31 $package_name = $options{package};
34 (defined $package_name && $package_name && !ref($package_name))
35 || confess "You must pass a package name and it cannot be blessed";
37 return Class::MOP::get_metaclass_by_name($package_name)
38 || $class->construct_class_instance(package => $package_name, @_);
41 # NOTE: (meta-circularity)
42 # this is a special form of &construct_instance
43 # (see below), which is used to construct class
44 # meta-object instances for any Class::MOP::*
45 # class. All other classes will use the more
46 # normal &construct_instance.
47 sub construct_class_instance {
49 my $options = @_ == 1 ? $_[0] : {@_};
50 my $package_name = $options->{package};
51 (defined $package_name && $package_name)
52 || confess "You must pass a package name";
54 # return the metaclass if we have it cached,
55 # and it is still defined (it has not been
56 # reaped by DESTROY yet, which can happen
57 # annoyingly enough during global destruction)
59 if (defined(my $meta = Class::MOP::get_metaclass_by_name($package_name))) {
64 # we need to deal with the possibility
65 # of class immutability here, and then
66 # get the name of the class appropriately
68 ? ($class->is_immutable
69 ? $class->get_mutable_metaclass_name()
73 # now create the metaclass
75 if ($class eq 'Class::MOP::Class') {
77 $meta = $class->_new($options)
81 # it is safe to use meta here because
82 # class will always be a subclass of
83 # Class::MOP::Class, which defines meta
84 $meta = $class->meta->construct_instance($options)
87 # and check the metaclass compatibility
88 $meta->check_metaclass_compatibility();
90 Class::MOP::store_metaclass_by_name($package_name, $meta);
93 # we need to weaken any anon classes
94 # so that they can call DESTROY properly
95 Class::MOP::weaken_metaclass($package_name) if $meta->is_anon_class;
102 my $options = @_ == 1 ? $_[0] : {@_};
105 # inherited from Class::MOP::Package
106 'package' => $options->{package},
109 # since the following attributes will
110 # actually be loaded from the symbol
111 # table, and actually bypass the instance
112 # entirely, we can just leave these things
113 # listed here for reference, because they
114 # should not actually have a value associated
116 'namespace' => \undef,
117 # inherited from Class::MOP::Module
119 'authority' => \undef,
120 # defined in Class::MOP::Class
121 'superclasses' => \undef,
125 'attribute_metaclass' => $options->{'attribute_metaclass'} || 'Class::MOP::Attribute',
126 'method_metaclass' => $options->{'method_metaclass'} || 'Class::MOP::Method',
127 'instance_metaclass' => $options->{'instance_metaclass'} || 'Class::MOP::Instance',
131 sub reset_package_cache_flag { (shift)->{'_package_cache_flag'} = undef }
132 sub update_package_cache_flag {
135 # we can manually update the cache number
136 # since we are actually adding the method
137 # to our cache as well. This avoids us
138 # having to regenerate the method_map.
140 $self->{'_package_cache_flag'} = Class::MOP::check_package_cache_flag($self->name);
143 sub check_metaclass_compatibility {
146 # this is always okay ...
147 return if ref($self) eq 'Class::MOP::Class' &&
148 $self->instance_metaclass eq 'Class::MOP::Instance';
150 my @class_list = $self->linearized_isa;
151 shift @class_list; # shift off $self->name
153 foreach my $class_name (@class_list) {
154 my $meta = Class::MOP::get_metaclass_by_name($class_name) || next;
157 # we need to deal with the possibility
158 # of class immutability here, and then
159 # get the name of the class appropriately
160 my $meta_type = ($meta->is_immutable
161 ? $meta->get_mutable_metaclass_name()
164 ($self->isa($meta_type))
165 || confess $self->name . "->meta => (" . (ref($self)) . ")" .
166 " is not compatible with the " .
167 $class_name . "->meta => (" . ($meta_type) . ")";
169 # we also need to check that instance metaclasses
170 # are compatibile in the same the class.
171 ($self->instance_metaclass->isa($meta->instance_metaclass))
172 || confess $self->name . "->meta->instance_metaclass => (" . ($self->instance_metaclass) . ")" .
173 " is not compatible with the " .
174 $class_name . "->meta->instance_metaclass => (" . ($meta->instance_metaclass) . ")";
178 # backwards compat for stevan's inability to spell ;)
179 sub check_metaclass_compatability {
181 $self->check_metaclass_compatibility(@_);
188 # this should be sufficient, if you have a
189 # use case where it is not, write a test and
191 my $ANON_CLASS_SERIAL = 0;
194 # we need a sufficiently annoying prefix
195 # this should suffice for now, this is
196 # used in a couple of places below, so
197 # need to put it up here for now.
198 my $ANON_CLASS_PREFIX = 'Class::MOP::Class::__ANON__::SERIAL::';
202 no warnings 'uninitialized';
203 $self->name =~ /^$ANON_CLASS_PREFIX/;
206 sub create_anon_class {
207 my ($class, %options) = @_;
208 my $package_name = $ANON_CLASS_PREFIX . ++$ANON_CLASS_SERIAL;
209 return $class->create($package_name, %options);
213 # this will only get called for
214 # anon-classes, all other calls
215 # are assumed to occur during
216 # global destruction and so don't
217 # really need to be handled explicitly
221 return if Class::MOP::in_global_destruction(); # it'll happen soon anyway and this just makes things more complicated
223 no warnings 'uninitialized';
224 return unless $self->name =~ /^$ANON_CLASS_PREFIX/;
225 # Moose does a weird thing where it replaces the metaclass for
226 # class when fixing metaclass incompatibility. In that case,
227 # we don't want to clean out the namespace now. We can detect
228 # that because Moose will explicitly update the singleton
229 # cache in Class::MOP.
230 my $current_meta = Class::MOP::get_metaclass_by_name($self->name);
231 return if $current_meta ne $self;
233 my ($serial_id) = ($self->name =~ /^$ANON_CLASS_PREFIX(\d+)/);
235 foreach my $key (keys %{$ANON_CLASS_PREFIX . $serial_id}) {
236 delete ${$ANON_CLASS_PREFIX . $serial_id}{$key};
238 delete ${'main::' . $ANON_CLASS_PREFIX}{$serial_id . '::'};
243 # creating classes with MOP ...
246 my ( $class, @args ) = @_;
248 unshift @args, 'package' if @args % 2 == 1;
250 my (%options) = @args;
251 my $package_name = $options{package};
253 (defined $package_name && $package_name)
254 || confess "You must pass a package name";
256 (ref $options{superclasses} eq 'ARRAY')
257 || confess "You must pass an ARRAY ref of superclasses"
258 if exists $options{superclasses};
260 (ref $options{attributes} eq 'ARRAY')
261 || confess "You must pass an ARRAY ref of attributes"
262 if exists $options{attributes};
264 (ref $options{methods} eq 'HASH')
265 || confess "You must pass an HASH ref of methods"
266 if exists $options{methods};
268 my $code = "package $package_name;";
269 $code .= "\$$package_name\:\:VERSION = '" . $options{version} . "';"
270 if exists $options{version};
271 $code .= "\$$package_name\:\:AUTHORITY = '" . $options{authority} . "';"
272 if exists $options{authority};
275 confess "creation of $package_name failed : $@" if $@;
277 my $meta = $class->initialize($package_name);
280 $meta->add_method('meta' => sub {
281 $class->initialize(ref($_[0]) || $_[0]);
284 $meta->superclasses(@{$options{superclasses}})
285 if exists $options{superclasses};
287 # process attributes first, so that they can
288 # install accessors, but locally defined methods
289 # can then overwrite them. It is maybe a little odd, but
290 # I think this should be the order of things.
291 if (exists $options{attributes}) {
292 foreach my $attr (@{$options{attributes}}) {
293 $meta->add_attribute($attr);
296 if (exists $options{methods}) {
297 foreach my $method_name (keys %{$options{methods}}) {
298 $meta->add_method($method_name, $options{methods}->{$method_name});
307 # all these attribute readers will be bootstrapped
308 # away in the Class::MOP bootstrap section
310 sub get_attribute_map { $_[0]->{'attributes'} }
311 sub attribute_metaclass { $_[0]->{'attribute_metaclass'} }
312 sub method_metaclass { $_[0]->{'method_metaclass'} }
313 sub instance_metaclass { $_[0]->{'instance_metaclass'} }
316 # this is a prime canidate for conversion to XS
320 my $current = Class::MOP::check_package_cache_flag($self->name);
322 if (defined $self->{'_package_cache_flag'} && $self->{'_package_cache_flag'} == $current) {
323 return $self->{'methods'} ||= {};
326 $self->{_package_cache_flag} = $current;
328 my $map = $self->{'methods'} ||= {};
330 my $class_name = $self->name;
331 my $method_metaclass = $self->method_metaclass;
333 my %all_code = $self->get_all_package_symbols('CODE');
335 foreach my $symbol (keys %all_code) {
336 my $code = $all_code{$symbol};
338 next if exists $map->{$symbol} &&
339 defined $map->{$symbol} &&
340 $map->{$symbol}->body == $code;
342 my ($pkg, $name) = Class::MOP::get_code_info($code);
345 # in 5.10 constant.pm the constants show up
346 # as being in the right package, but in pre-5.10
347 # they show up as constant::__ANON__ so we
348 # make an exception here to be sure that things
349 # work as expected in both.
351 unless ($pkg eq 'constant' && $name eq '__ANON__') {
352 next if ($pkg || '') ne $class_name ||
353 (($name || '') ne '__ANON__' && ($pkg || '') ne $class_name);
356 $map->{$symbol} = $method_metaclass->wrap(
358 associated_metaclass => $self,
359 package_name => $class_name,
367 # Instance Construction & Cloning
373 # we need to protect the integrity of the
374 # Class::MOP::Class singletons here, so we
375 # delegate this to &construct_class_instance
376 # which will deal with the singletons
377 return $class->construct_class_instance(@_)
378 if $class->name->isa('Class::MOP::Class');
379 return $class->construct_instance(@_);
382 sub construct_instance {
384 my $params = @_ == 1 ? $_[0] : {@_};
385 my $meta_instance = $class->get_meta_instance();
386 my $instance = $meta_instance->create_instance();
387 foreach my $attr ($class->compute_all_applicable_attributes()) {
388 $attr->initialize_instance_slot($meta_instance, $instance, $params);
391 # this will only work for a HASH instance type
392 if ($class->is_anon_class) {
393 (Scalar::Util::reftype($instance) eq 'HASH')
394 || confess "Currently only HASH based instances are supported with instance of anon-classes";
396 # At some point we should make this official
397 # as a reserved slot name, but right now I am
398 # going to keep it here.
399 # my $RESERVED_MOP_SLOT = '__MOP__';
400 $instance->{'__MOP__'} = $class;
406 sub get_meta_instance {
408 $self->{'_meta_instance'} ||= $self->create_meta_instance();
411 sub create_meta_instance {
414 my $instance = $self->instance_metaclass->new(
415 associated_metaclass => $self,
416 attributes => [ $self->compute_all_applicable_attributes() ],
419 $self->add_meta_instance_dependencies()
420 if $instance->is_dependent_on_superclasses();
427 my $instance = shift;
428 (blessed($instance) && $instance->isa($class->name))
429 || confess "You must pass an instance of the metaclass (" . (ref $class ? $class->name : $class) . "), not ($instance)";
432 # we need to protect the integrity of the
433 # Class::MOP::Class singletons here, they
434 # should not be cloned.
435 return $instance if $instance->isa('Class::MOP::Class');
436 $class->clone_instance($instance, @_);
440 my ($class, $instance, %params) = @_;
442 || confess "You can only clone instances, ($instance) is not a blessed instance";
443 my $meta_instance = $class->get_meta_instance();
444 my $clone = $meta_instance->clone_instance($instance);
445 foreach my $attr ($class->compute_all_applicable_attributes()) {
446 if ( defined( my $init_arg = $attr->init_arg ) ) {
447 if (exists $params{$init_arg}) {
448 $attr->set_value($clone, $params{$init_arg});
455 sub rebless_instance {
456 my ($self, $instance, %params) = @_;
459 if ($instance->can('meta')) {
460 ($instance->meta->isa('Class::MOP::Class'))
461 || confess 'Cannot rebless instance if ->meta is not an instance of Class::MOP::Class';
462 $old_metaclass = $instance->meta;
465 $old_metaclass = $self->initialize(ref($instance));
468 my $meta_instance = $self->get_meta_instance();
470 $self->name->isa($old_metaclass->name)
471 || confess "You may rebless only into a subclass of (". $old_metaclass->name ."), of which (". $self->name .") isn't.";
474 $meta_instance->rebless_instance_structure($instance, $self);
476 foreach my $attr ( $self->compute_all_applicable_attributes ) {
477 if ( $attr->has_value($instance) ) {
478 if ( defined( my $init_arg = $attr->init_arg ) ) {
479 $params{$init_arg} = $attr->get_value($instance)
480 unless exists $params{$init_arg};
483 $attr->set_value($instance, $attr->get_value($instance));
488 foreach my $attr ($self->compute_all_applicable_attributes) {
489 $attr->initialize_instance_slot($meta_instance, $instance, \%params);
499 my $var_spec = { sigil => '@', type => 'ARRAY', name => 'ISA' };
502 @{$self->get_package_symbol($var_spec)} = @supers;
505 # on 5.8 and below, we need to call
506 # a method to get Perl to detect
507 # a cycle in the class hierarchy
508 my $class = $self->name;
512 # we need to check the metaclass
513 # compatibility here so that we can
514 # be sure that the superclass is
515 # not potentially creating an issues
516 # we don't know about
518 $self->check_metaclass_compatibility();
519 $self->update_meta_instance_dependencies();
521 @{$self->get_package_symbol($var_spec)};
527 my $super_class = $self->name;
529 if ( Class::MOP::HAVE_ISAREV() ) {
530 return @{ $super_class->mro::get_isarev() };
534 my $find_derived_classes;
535 $find_derived_classes = sub {
536 my ($outer_class) = @_;
538 my $symbol_table_hashref = do { no strict 'refs'; \%{"${outer_class}::"} };
541 for my $symbol ( keys %$symbol_table_hashref ) {
542 next SYMBOL if $symbol !~ /\A (\w+):: \z/x;
543 my $inner_class = $1;
545 next SYMBOL if $inner_class eq 'SUPER'; # skip '*::SUPER'
549 ? "${outer_class}::$inner_class"
552 if ( $class->isa($super_class) and $class ne $super_class ) {
553 push @derived_classes, $class;
556 next SYMBOL if $class eq 'main'; # skip 'main::*'
558 $find_derived_classes->($class);
562 my $root_class = q{};
563 $find_derived_classes->($root_class);
565 undef $find_derived_classes;
567 @derived_classes = sort { $a->isa($b) ? 1 : $b->isa($a) ? -1 : 0 } @derived_classes;
569 return @derived_classes;
575 return @{ mro::get_linear_isa( (shift)->name ) };
578 sub class_precedence_list {
580 my $name = $self->name;
582 unless (Class::MOP::IS_RUNNING_ON_5_10()) {
584 # We need to check for circular inheritance here
585 # if we are are not on 5.10, cause 5.8 detects it
586 # late. This will do nothing if all is well, and
587 # blow up otherwise. Yes, it's an ugly hack, better
588 # suggestions are welcome.
590 ($name || return)->isa('This is a test for circular inheritance')
593 # if our mro is c3, we can
594 # just grab the linear_isa
595 if (mro::get_mro($name) eq 'c3') {
596 return @{ mro::get_linear_isa($name) }
600 # we can't grab the linear_isa for dfs
601 # since it has all the duplicates
606 $self->initialize($_)->class_precedence_list()
607 } $self->superclasses()
614 sub wrap_method_body {
615 my ( $self, %args ) = @_;
617 ('CODE' eq ref $args{body})
618 || confess "Your code block must be a CODE reference";
620 $self->method_metaclass->wrap(
621 package_name => $self->name,
627 my ($self, $method_name, $method) = @_;
628 (defined $method_name && $method_name)
629 || confess "You must define a method name";
632 if (blessed($method)) {
633 $body = $method->body;
634 if ($method->package_name ne $self->name) {
635 $method = $method->clone(
636 package_name => $self->name,
638 ) if $method->can('clone');
643 $method = $self->wrap_method_body( body => $body, name => $method_name );
646 $method->attach_to_class($self);
648 $self->get_method_map->{$method_name} = $method;
650 my $full_method_name = ($self->name . '::' . $method_name);
651 $self->add_package_symbol(
652 { sigil => '&', type => 'CODE', name => $method_name },
653 Class::MOP::subname($full_method_name => $body)
656 $self->update_package_cache_flag; # still valid, since we just added the method to the map, and if it was invalid before that then get_method_map updated it
660 my $fetch_and_prepare_method = sub {
661 my ($self, $method_name) = @_;
663 my $method = $self->get_method($method_name);
664 # if we dont have local ...
666 # try to find the next method
667 $method = $self->find_next_method_by_name($method_name);
668 # die if it does not exist
670 || confess "The method '$method_name' is not found in the inheritance hierarchy for class " . $self->name;
671 # and now make sure to wrap it
672 # even if it is already wrapped
673 # because we need a new sub ref
674 $method = Class::MOP::Method::Wrapped->wrap($method);
677 # now make sure we wrap it properly
678 $method = Class::MOP::Method::Wrapped->wrap($method)
679 unless $method->isa('Class::MOP::Method::Wrapped');
681 $self->add_method($method_name => $method);
685 sub add_before_method_modifier {
686 my ($self, $method_name, $method_modifier) = @_;
687 (defined $method_name && $method_name)
688 || confess "You must pass in a method name";
689 my $method = $fetch_and_prepare_method->($self, $method_name);
690 $method->add_before_modifier(
691 Class::MOP::subname(':before' => $method_modifier)
695 sub add_after_method_modifier {
696 my ($self, $method_name, $method_modifier) = @_;
697 (defined $method_name && $method_name)
698 || confess "You must pass in a method name";
699 my $method = $fetch_and_prepare_method->($self, $method_name);
700 $method->add_after_modifier(
701 Class::MOP::subname(':after' => $method_modifier)
705 sub add_around_method_modifier {
706 my ($self, $method_name, $method_modifier) = @_;
707 (defined $method_name && $method_name)
708 || confess "You must pass in a method name";
709 my $method = $fetch_and_prepare_method->($self, $method_name);
710 $method->add_around_modifier(
711 Class::MOP::subname(':around' => $method_modifier)
716 # the methods above used to be named like this:
717 # ${pkg}::${method}:(before|after|around)
718 # but this proved problematic when using one modifier
719 # to wrap multiple methods (something which is likely
720 # to happen pretty regularly IMO). So instead of naming
721 # it like this, I have chosen to just name them purely
722 # with their modifier names, like so:
723 # :(before|after|around)
724 # The fact is that in a stack trace, it will be fairly
725 # evident from the context what method they are attached
726 # to, and so don't need the fully qualified name.
732 $self->add_method(@_);
736 my ($self, $method_name) = @_;
737 (defined $method_name && $method_name)
738 || confess "You must define a method name";
740 exists $self->get_method_map->{$method_name};
744 my ($self, $method_name) = @_;
745 (defined $method_name && $method_name)
746 || confess "You must define a method name";
749 # I don't really need this here, because
750 # if the method_map is missing a key it
751 # will just return undef for me now
752 # return unless $self->has_method($method_name);
754 return $self->get_method_map->{$method_name};
758 my ($self, $method_name) = @_;
759 (defined $method_name && $method_name)
760 || confess "You must define a method name";
762 my $removed_method = delete $self->get_method_map->{$method_name};
764 $self->remove_package_symbol(
765 { sigil => '&', type => 'CODE', name => $method_name }
768 $removed_method->detach_from_class if $removed_method;
770 $self->update_package_cache_flag; # still valid, since we just removed the method from the map
772 return $removed_method;
775 sub get_method_list {
777 keys %{$self->get_method_map};
780 sub find_method_by_name {
781 my ($self, $method_name) = @_;
782 (defined $method_name && $method_name)
783 || confess "You must define a method name to find";
784 foreach my $class ($self->linearized_isa) {
785 # fetch the meta-class ...
786 my $meta = $self->initialize($class);
787 return $meta->get_method($method_name)
788 if $meta->has_method($method_name);
793 sub get_all_methods {
795 my %methods = map { %{ $self->initialize($_)->get_method_map } } reverse $self->linearized_isa;
796 return values %methods;
800 sub compute_all_applicable_methods {
804 class => $_->package_name,
805 code => $_, # sigh, overloading
807 } shift->get_all_methods(@_);
810 sub find_all_methods_by_name {
811 my ($self, $method_name) = @_;
812 (defined $method_name && $method_name)
813 || confess "You must define a method name to find";
815 foreach my $class ($self->linearized_isa) {
816 # fetch the meta-class ...
817 my $meta = $self->initialize($class);
819 name => $method_name,
821 code => $meta->get_method($method_name)
822 } if $meta->has_method($method_name);
827 sub find_next_method_by_name {
828 my ($self, $method_name) = @_;
829 (defined $method_name && $method_name)
830 || confess "You must define a method name to find";
831 my @cpl = $self->linearized_isa;
832 shift @cpl; # discard ourselves
833 foreach my $class (@cpl) {
834 # fetch the meta-class ...
835 my $meta = $self->initialize($class);
836 return $meta->get_method($method_name)
837 if $meta->has_method($method_name);
846 # either we have an attribute object already
847 # or we need to create one from the args provided
848 my $attribute = blessed($_[0]) ? $_[0] : $self->attribute_metaclass->new(@_);
849 # make sure it is derived from the correct type though
850 ($attribute->isa('Class::MOP::Attribute'))
851 || confess "Your attribute must be an instance of Class::MOP::Attribute (or a subclass)";
853 # first we attach our new attribute
854 # because it might need certain information
855 # about the class which it is attached to
856 $attribute->attach_to_class($self);
858 # then we remove attributes of a conflicting
859 # name here so that we can properly detach
860 # the old attr object, and remove any
861 # accessors it would have generated
862 if ( $self->has_attribute($attribute->name) ) {
863 $self->remove_attribute($attribute->name);
865 $self->invalidate_meta_instances();
868 # then onto installing the new accessors
869 $self->get_attribute_map->{$attribute->name} = $attribute;
871 # invalidate package flag here
872 my $e = do { local $@; eval { $attribute->install_accessors() }; $@ };
874 $self->remove_attribute($attribute->name);
881 sub update_meta_instance_dependencies {
884 if ( $self->{meta_instance_dependencies} ) {
885 return $self->add_meta_instance_dependencies;
889 sub add_meta_instance_dependencies {
892 $self->remove_meta_instance_depdendencies;
894 my @attrs = $self->compute_all_applicable_attributes();
897 my @classes = grep { not $seen{$_->name}++ } map { $_->associated_class } @attrs;
899 foreach my $class ( @classes ) {
900 $class->add_dependent_meta_instance($self);
903 $self->{meta_instance_dependencies} = \@classes;
906 sub remove_meta_instance_depdendencies {
909 if ( my $classes = delete $self->{meta_instance_dependencies} ) {
910 foreach my $class ( @$classes ) {
911 $class->remove_dependent_meta_instance($self);
921 sub add_dependent_meta_instance {
922 my ( $self, $metaclass ) = @_;
923 push @{ $self->{dependent_meta_instances} }, $metaclass;
926 sub remove_dependent_meta_instance {
927 my ( $self, $metaclass ) = @_;
928 my $name = $metaclass->name;
929 @$_ = grep { $_->name ne $name } @$_ for $self->{dependent_meta_instances};
932 sub invalidate_meta_instances {
934 $_->invalidate_meta_instance() for $self, @{ $self->{dependent_meta_instances} };
937 sub invalidate_meta_instance {
939 undef $self->{_meta_instance};
943 my ($self, $attribute_name) = @_;
944 (defined $attribute_name && $attribute_name)
945 || confess "You must define an attribute name";
946 exists $self->get_attribute_map->{$attribute_name};
950 my ($self, $attribute_name) = @_;
951 (defined $attribute_name && $attribute_name)
952 || confess "You must define an attribute name";
953 return $self->get_attribute_map->{$attribute_name}
955 # this will return undef anyway, so no need ...
956 # if $self->has_attribute($attribute_name);
960 sub remove_attribute {
961 my ($self, $attribute_name) = @_;
962 (defined $attribute_name && $attribute_name)
963 || confess "You must define an attribute name";
964 my $removed_attribute = $self->get_attribute_map->{$attribute_name};
965 return unless defined $removed_attribute;
966 delete $self->get_attribute_map->{$attribute_name};
967 $self->invalidate_meta_instances();
968 $removed_attribute->remove_accessors();
969 $removed_attribute->detach_from_class();
970 return $removed_attribute;
973 sub get_attribute_list {
975 keys %{$self->get_attribute_map};
978 sub get_all_attributes {
979 shift->compute_all_applicable_attributes(@_);
982 sub compute_all_applicable_attributes {
984 my %attrs = map { %{ $self->initialize($_)->get_attribute_map } } reverse $self->linearized_isa;
985 return values %attrs;
988 sub find_attribute_by_name {
989 my ($self, $attr_name) = @_;
990 foreach my $class ($self->linearized_isa) {
991 # fetch the meta-class ...
992 my $meta = $self->initialize($class);
993 return $meta->get_attribute($attr_name)
994 if $meta->has_attribute($attr_name);
999 # check if we can reinitialize
1003 # if any local attr is defined
1004 return if $self->get_attribute_list;
1006 # or any non-declared methods
1007 if ( my @methods = values %{ $self->get_method_map } ) {
1008 my $metaclass = $self->method_metaclass;
1009 foreach my $method ( @methods ) {
1010 return if $method->isa("Class::MOP::Method::Generated");
1011 # FIXME do we need to enforce this too? return unless $method->isa($metaclass);
1020 sub is_mutable { 1 }
1021 sub is_immutable { 0 }
1024 # Why I changed this (groditi)
1025 # - One Metaclass may have many Classes through many Metaclass instances
1026 # - One Metaclass should only have one Immutable Transformer instance
1027 # - Each Class may have different Immutabilizing options
1028 # - Therefore each Metaclass instance may have different Immutabilizing options
1029 # - We need to store one Immutable Transformer instance per Metaclass
1030 # - We need to store one set of Immutable Transformer options per Class
1031 # - Upon make_mutable we may delete the Immutabilizing options
1032 # - We could clean the immutable Transformer instance when there is no more
1033 # immutable Classes of that type, but we can also keep it in case
1034 # another class with this same Metaclass becomes immutable. It is a case
1035 # of trading of storing an instance to avoid unnecessary instantiations of
1036 # Immutable Transformers. You may view this as a memory leak, however
1037 # Because we have few Metaclasses, in practice it seems acceptable
1038 # - To allow Immutable Transformers instances to be cleaned up we could weaken
1039 # the reference stored in $IMMUTABLE_TRANSFORMERS{$class} and ||= should DWIM
1043 my %IMMUTABLE_TRANSFORMERS;
1044 my %IMMUTABLE_OPTIONS;
1046 sub get_immutable_options {
1048 return if $self->is_mutable;
1049 confess "unable to find immutabilizing options"
1050 unless exists $IMMUTABLE_OPTIONS{$self->name};
1051 my %options = %{$IMMUTABLE_OPTIONS{$self->name}};
1052 delete $options{IMMUTABLE_TRANSFORMER};
1056 sub get_immutable_transformer {
1058 if( $self->is_mutable ){
1059 my $class = ref $self || $self;
1060 return $IMMUTABLE_TRANSFORMERS{$class} ||= $self->create_immutable_transformer;
1062 confess "unable to find transformer for immutable class"
1063 unless exists $IMMUTABLE_OPTIONS{$self->name};
1064 return $IMMUTABLE_OPTIONS{$self->name}->{IMMUTABLE_TRANSFORMER};
1067 sub make_immutable {
1071 my $transformer = $self->get_immutable_transformer;
1072 $transformer->make_metaclass_immutable($self, \%options);
1073 $IMMUTABLE_OPTIONS{$self->name} =
1074 { %options, IMMUTABLE_TRANSFORMER => $transformer };
1076 if( exists $options{debug} && $options{debug} ){
1077 print STDERR "# of Metaclass options: ", keys %IMMUTABLE_OPTIONS;
1078 print STDERR "# of Immutable transformers: ", keys %IMMUTABLE_TRANSFORMERS;
1086 return if $self->is_mutable;
1087 my $options = delete $IMMUTABLE_OPTIONS{$self->name};
1088 confess "unable to find immutabilizing options" unless ref $options;
1089 my $transformer = delete $options->{IMMUTABLE_TRANSFORMER};
1090 $transformer->make_metaclass_mutable($self, $options);
1095 sub create_immutable_transformer {
1097 my $class = Class::MOP::Immutable->new($self, {
1098 read_only => [qw/superclasses/],
1105 remove_package_symbol
1108 class_precedence_list => 'ARRAY',
1109 linearized_isa => 'ARRAY', # FIXME perl 5.10 memoizes this on its own, no need?
1110 get_all_methods => 'ARRAY',
1111 #get_all_attributes => 'ARRAY', # it's an alias, no need, but maybe in the future
1112 compute_all_applicable_attributes => 'ARRAY',
1113 get_meta_instance => 'SCALAR',
1114 get_method_map => 'SCALAR',
1117 # this is ugly, but so are typeglobs,
1118 # so whattayahgonnadoboutit
1121 add_package_symbol => sub {
1122 my $original = shift;
1123 confess "Cannot add package symbols to an immutable metaclass"
1124 unless (caller(2))[3] eq 'Class::MOP::Package::get_package_symbol';
1126 # This is a workaround for a bug in 5.8.1 which thinks that
1127 # goto $original->body
1128 # is trying to go to a label
1129 my $body = $original->body;
1145 Class::MOP::Class - Class Meta Object
1149 # assuming that class Foo
1150 # has been defined, you can
1152 # use this for introspection ...
1154 # add a method to Foo ...
1155 Foo->meta->add_method('bar' => sub { ... })
1157 # get a list of all the classes searched
1158 # the method dispatcher in the correct order
1159 Foo->meta->class_precedence_list()
1161 # remove a method from Foo
1162 Foo->meta->remove_method('bar');
1164 # or use this to actually create classes ...
1166 Class::MOP::Class->create('Bar' => (
1168 superclasses => [ 'Foo' ],
1170 Class::MOP:::Attribute->new('$bar'),
1171 Class::MOP:::Attribute->new('$baz'),
1174 calculate_bar => sub { ... },
1175 construct_baz => sub { ... }
1181 This is the largest and currently most complex part of the Perl 5
1182 meta-object protocol. It controls the introspection and
1183 manipulation of Perl 5 classes (and it can create them too). The
1184 best way to understand what this module can do, is to read the
1185 documentation for each of it's methods.
1189 =head2 Self Introspection
1195 This will return a B<Class::MOP::Class> instance which is related
1196 to this class. Thereby allowing B<Class::MOP::Class> to actually
1199 As with B<Class::MOP::Attribute>, B<Class::MOP> will actually
1200 bootstrap this module by installing a number of attribute meta-objects
1201 into it's metaclass. This will allow this class to reap all the benifits
1202 of the MOP when subclassing it.
1206 =head2 Class construction
1208 These methods will handle creating B<Class::MOP::Class> objects,
1209 which can be used to both create new classes, and analyze
1210 pre-existing classes.
1212 This module will internally store references to all the instances
1213 you create with these methods, so that they do not need to be
1214 created any more than nessecary. Basically, they are singletons.
1218 =item B<create ($package_name,
1219 version =E<gt> ?$version,
1220 authority =E<gt> ?$authority,
1221 superclasses =E<gt> ?@superclasses,
1222 methods =E<gt> ?%methods,
1223 attributes =E<gt> ?%attributes)>
1225 This returns a B<Class::MOP::Class> object, bringing the specified
1226 C<$package_name> into existence and adding any of the C<$version>,
1227 C<$authority>, C<@superclasses>, C<%methods> and C<%attributes> to
1230 =item B<create_anon_class (superclasses =E<gt> ?@superclasses,
1231 methods =E<gt> ?%methods,
1232 attributes =E<gt> ?%attributes)>
1234 This will create an anonymous class, it works much like C<create> but
1235 it does not need a C<$package_name>. Instead it will create a suitably
1236 unique package name for you to stash things into.
1238 On very important distinction is that anon classes are destroyed once
1239 the metaclass they are attached to goes out of scope. In the DESTROY
1240 method, the created package will be removed from the symbol table.
1242 It is also worth noting that any instances created with an anon-class
1243 will keep a special reference to the anon-meta which will prevent the
1244 anon-class from going out of scope until all instances of it have also
1245 been destroyed. This however only works for HASH based instance types,
1246 as we use a special reserved slot (C<__MOP__>) to store this.
1248 =item B<initialize ($package_name, %options)>
1250 This initializes and returns returns a B<Class::MOP::Class> object
1251 for a given a C<$package_name>.
1253 =item B<construct_class_instance (%options)>
1255 This will construct an instance of B<Class::MOP::Class>, it is
1256 here so that we can actually "tie the knot" for B<Class::MOP::Class>
1257 to use C<construct_instance> once all the bootstrapping is done. This
1258 method is used internally by C<initialize> and should never be called
1259 from outside of that method really.
1261 =item B<check_metaclass_compatibility>
1263 This method is called as the very last thing in the
1264 C<construct_class_instance> method. This will check that the
1265 metaclass you are creating is compatible with the metaclasses of all
1266 your ancestors. For more inforamtion about metaclass compatibility
1267 see the C<About Metaclass compatibility> section in L<Class::MOP>.
1269 =item B<update_package_cache_flag>
1271 This will reset the package cache flag for this particular metaclass
1272 it is basically the value of the C<Class::MOP::get_package_cache_flag>
1273 function. This is very rarely needed from outside of C<Class::MOP::Class>
1274 but in some cases you might want to use it, so it is here.
1276 =item B<reset_package_cache_flag>
1278 Clears the package cache flag to announce to the internals that we need
1279 to rebuild the method map.
1281 =item B<add_meta_instance_dependencies>
1283 Registers this class as dependent on its superclasses.
1285 Only superclasses from which this class inherits attributes will be added.
1287 =item B<remove_meta_instance_depdendencies>
1289 Unregisters this class from its superclasses.
1291 =item B<update_meta_instance_dependencies>
1293 Reregisters if necessary.
1295 =item B<add_dependent_meta_instance> $metaclass
1297 Registers the class as having a meta instance dependent on this class.
1299 =item B<remove_dependent_meta_instance> $metaclass
1301 Remove the class from the list of dependent classes.
1303 =item B<invalidate_meta_instances>
1305 Clears the cached meta instance for this metaclass and all of the registered
1306 classes with dependent meta instances.
1308 Called by C<add_attribute> and C<remove_attribute> to recalculate the attribute
1311 =item B<invalidate_meta_instance>
1313 Used by C<invalidate_meta_instances>.
1317 =head2 Object instance construction and cloning
1319 These methods are B<entirely optional>, it is up to you whether you want
1324 =item B<instance_metaclass>
1326 Returns the class name of the instance metaclass, see L<Class::MOP::Instance>
1327 for more information on the instance metaclasses.
1329 =item B<get_meta_instance>
1331 Returns an instance of L<Class::MOP::Instance> to be used in the construction
1332 of a new instance of the class.
1334 =item B<create_meta_instance>
1336 Called by C<get_meta_instance> if necessary.
1338 =item B<new_object (%params)>
1340 This is a convience method for creating a new object of the class, and
1341 blessing it into the appropriate package as well. Ideally your class
1342 would call a C<new> this method like so:
1345 my ($class, %param) = @_;
1346 $class->meta->new_object(%params);
1349 =item B<construct_instance (%params)>
1351 This method is used to construct an instance structure suitable for
1352 C<bless>-ing into your package of choice. It works in conjunction
1353 with the Attribute protocol to collect all applicable attributes.
1355 This will construct and instance using a HASH ref as storage
1356 (currently only HASH references are supported). This will collect all
1357 the applicable attributes and layout out the fields in the HASH ref,
1358 it will then initialize them using either use the corresponding key
1359 in C<%params> or any default value or initializer found in the
1360 attribute meta-object.
1362 =item B<clone_object ($instance, %params)>
1364 This is a convience method for cloning an object instance, then
1365 blessing it into the appropriate package. This method will call
1366 C<clone_instance>, which performs a shallow copy of the object,
1367 see that methods documentation for more details. Ideally your
1368 class would call a C<clone> this method like so:
1370 sub MyClass::clone {
1371 my ($self, %param) = @_;
1372 $self->meta->clone_object($self, %params);
1375 =item B<clone_instance($instance, %params)>
1377 This method is a compliment of C<construct_instance> (which means if
1378 you override C<construct_instance>, you need to override this one too),
1379 and clones the instance shallowly.
1381 The cloned structure returned is (like with C<construct_instance>) an
1382 unC<bless>ed HASH reference, it is your responsibility to then bless
1383 this cloned structure into the right class (which C<clone_object> will
1386 As of 0.11, this method will clone the C<$instance> structure shallowly,
1387 as opposed to the deep cloning implemented in prior versions. After much
1388 thought, research and discussion, I have decided that anything but basic
1389 shallow cloning is outside the scope of the meta-object protocol. I
1390 think Yuval "nothingmuch" Kogman put it best when he said that cloning
1391 is too I<context-specific> to be part of the MOP.
1393 =item B<rebless_instance($instance, ?%params)>
1395 This will change the class of C<$instance> to the class of the invoking
1396 C<Class::MOP::Class>. You may only rebless the instance to a subclass of
1397 itself. You may pass in optional C<%params> which are like constructor
1398 params and will override anything already defined in the instance.
1402 =head2 Informational
1404 These are a few predicate methods for asking information about the class.
1408 =item B<is_anon_class>
1410 This returns true if the class is a C<Class::MOP::Class> created anon class.
1414 This returns true if the class is still mutable.
1416 =item B<is_immutable>
1418 This returns true if the class has been made immutable.
1420 =item B<is_pristine>
1422 Checks whether the class has any data that will be lost if C<reinitialize> is
1427 =head2 Inheritance Relationships
1431 =item B<superclasses (?@superclasses)>
1433 This is a read-write attribute which represents the superclass
1434 relationships of the class the B<Class::MOP::Class> instance is
1435 associated with. Basically, it can get and set the C<@ISA> for you.
1437 =item B<class_precedence_list>
1439 This computes the a list of all the class's ancestors in the same order
1440 in which method dispatch will be done. This is similair to what
1441 B<Class::ISA::super_path> does, but we don't remove duplicate names.
1443 =item B<linearized_isa>
1445 This returns a list based on C<class_precedence_list> but with all
1450 This returns a list of subclasses for this class.
1458 =item B<get_method_map>
1460 Returns a HASH ref of name to CODE reference mapping for this class.
1462 =item B<method_metaclass>
1464 Returns the class name of the method metaclass, see L<Class::MOP::Method>
1465 for more information on the method metaclasses.
1467 =item B<wrap_method_body(%attrs)>
1469 Wrap a code ref (C<$attrs{body>) with C<method_metaclass>.
1471 =item B<add_method ($method_name, $method, %attrs)>
1473 This will take a C<$method_name> and CODE reference or meta method
1474 objectand install it into the class's package.
1476 You are strongly encouraged to pass a meta method object instead of a
1477 code reference. If you do so, that object gets stored as part of the
1478 class's method map, providing more useful information about the method
1481 When you provide a method object, this method will clone that object
1482 if the object's package name does not match the class name. This lets
1483 us track the original source of any methods added from other classes
1484 (notably Moose roles).
1487 This does absolutely nothing special to C<$method>
1488 other than use B<Sub::Name> to make sure it is tagged with the
1489 correct name, and therefore show up correctly in stack traces and
1492 =item B<has_method ($method_name)>
1494 This just provides a simple way to check if the class implements
1495 a specific C<$method_name>. It will I<not> however, attempt to check
1496 if the class inherits the method (use C<UNIVERSAL::can> for that).
1498 This will correctly handle functions defined outside of the package
1499 that use a fully qualified name (C<sub Package::name { ... }>).
1501 This will correctly handle functions renamed with B<Sub::Name> and
1502 installed using the symbol tables. However, if you are naming the
1503 subroutine outside of the package scope, you must use the fully
1504 qualified name, including the package name, for C<has_method> to
1505 correctly identify it.
1507 This will attempt to correctly ignore functions imported from other
1508 packages using B<Exporter>. It breaks down if the function imported
1509 is an C<__ANON__> sub (such as with C<use constant>), which very well
1510 may be a valid method being applied to the class.
1512 In short, this method cannot always be trusted to determine if the
1513 C<$method_name> is actually a method. However, it will DWIM about
1514 90% of the time, so it's a small trade off I think.
1516 =item B<get_method ($method_name)>
1518 This will return a Class::MOP::Method instance related to the specified
1519 C<$method_name>, or return undef if that method does not exist.
1521 The Class::MOP::Method is codifiable, so you can use it like a normal
1522 CODE reference, see L<Class::MOP::Method> for more information.
1524 =item B<find_method_by_name ($method_name)>
1526 This will return a CODE reference of the specified C<$method_name>,
1527 or return undef if that method does not exist.
1529 Unlike C<get_method> this will also look in the superclasses.
1531 =item B<remove_method ($method_name)>
1533 This will attempt to remove a given C<$method_name> from the class.
1534 It will return the CODE reference that it has removed, and will
1535 attempt to use B<Sub::Name> to clear the methods associated name.
1537 =item B<get_method_list>
1539 This will return a list of method names for all I<locally> defined
1540 methods. It does B<not> provide a list of all applicable methods,
1541 including any inherited ones. If you want a list of all applicable
1542 methods, use the C<compute_all_applicable_methods> method.
1544 =item B<get_all_methods>
1546 This will traverse the inheritance heirachy and return a list of all
1547 the applicable L<Class::MOP::Method> objects for this class.
1549 =item B<compute_all_applicable_methods>
1553 This method returns a list of hashes describing the all the methods of the
1556 Use L<get_all_methods>, which is easier/better/faster. This method predates
1557 L<Class::MOP::Method>.
1559 =item B<find_all_methods_by_name ($method_name)>
1561 This will traverse the inheritence hierarchy and locate all methods
1562 with a given C<$method_name>. Similar to
1563 C<compute_all_applicable_methods> it returns a list of HASH references
1564 with the following information; method name (which will always be the
1565 same as C<$method_name>), the name of the class in which the method
1566 lives and a CODE reference for the actual method.
1568 The list of methods produced is a distinct list, meaning there are no
1569 duplicates in it. This is especially useful for things like object
1570 initialization and destruction where you only want the method called
1571 once, and in the correct order.
1573 =item B<find_next_method_by_name ($method_name)>
1575 This will return the first method to match a given C<$method_name> in
1576 the superclasses, this is basically equivalent to calling
1577 C<SUPER::$method_name>, but it can be dispatched at runtime.
1579 =item B<alias_method ($method_name, $method)>
1581 B<NOTE>: This method is now deprecated. Just use C<add_method>
1586 =head2 Method Modifiers
1588 Method modifiers are a concept borrowed from CLOS, in which a method
1589 can be wrapped with I<before>, I<after> and I<around> method modifiers
1590 that will be called everytime the method is called.
1592 =head3 How method modifiers work?
1594 Method modifiers work by wrapping the original method and then replacing
1595 it in the classes symbol table. The wrappers will handle calling all the
1596 modifiers in the appropariate orders and preserving the calling context
1597 for the original method.
1599 Each method modifier serves a particular purpose, which may not be
1600 obvious to users of other method wrapping modules. To start with, the
1601 return values of I<before> and I<after> modifiers are ignored. This is
1602 because thier purpose is B<not> to filter the input and output of the
1603 primary method (this is done with an I<around> modifier). This may seem
1604 like an odd restriction to some, but doing this allows for simple code
1605 to be added at the begining or end of a method call without jeapordizing
1606 the normal functioning of the primary method or placing any extra
1607 responsibility on the code of the modifier. Of course if you have more
1608 complex needs, then use the I<around> modifier, which uses a variation
1609 of continutation passing style to allow for a high degree of flexibility.
1611 Before and around modifiers are called in last-defined-first-called order,
1612 while after modifiers are called in first-defined-first-called order. So
1613 the call tree might looks something like this:
1623 To see examples of using method modifiers, see the following examples
1624 included in the distribution; F<InstanceCountingClass>, F<Perl6Attribute>,
1625 F<AttributesWithHistory> and F<C3MethodDispatchOrder>. There is also a
1626 classic CLOS usage example in the test F<017_add_method_modifier.t>.
1628 =head3 What is the performance impact?
1630 Of course there is a performance cost associated with method modifiers,
1631 but we have made every effort to make that cost be directly proportional
1632 to the amount of modifier features you utilize.
1634 The wrapping method does it's best to B<only> do as much work as it
1635 absolutely needs to. In order to do this we have moved some of the
1636 performance costs to set-up time, where they are easier to amortize.
1638 All this said, my benchmarks have indicated the following:
1640 simple wrapper with no modifiers 100% slower
1641 simple wrapper with simple before modifier 400% slower
1642 simple wrapper with simple after modifier 450% slower
1643 simple wrapper with simple around modifier 500-550% slower
1644 simple wrapper with all 3 modifiers 1100% slower
1646 These numbers may seem daunting, but you must remember, every feature
1647 comes with some cost. To put things in perspective, just doing a simple
1648 C<AUTOLOAD> which does nothing but extract the name of the method called
1649 and return it costs about 400% over a normal method call.
1653 =item B<add_before_method_modifier ($method_name, $code)>
1655 This will wrap the method at C<$method_name> and the supplied C<$code>
1656 will be passed the C<@_> arguments, and called before the original
1657 method is called. As specified above, the return value of the I<before>
1658 method modifiers is ignored, and it's ability to modify C<@_> is
1659 fairly limited. If you need to do either of these things, use an
1660 C<around> method modifier.
1662 =item B<add_after_method_modifier ($method_name, $code)>
1664 This will wrap the method at C<$method_name> so that the original
1665 method will be called, it's return values stashed, and then the
1666 supplied C<$code> will be passed the C<@_> arguments, and called.
1667 As specified above, the return value of the I<after> method
1668 modifiers is ignored, and it cannot modify the return values of
1669 the original method. If you need to do either of these things, use an
1670 C<around> method modifier.
1672 =item B<add_around_method_modifier ($method_name, $code)>
1674 This will wrap the method at C<$method_name> so that C<$code>
1675 will be called and passed the original method as an extra argument
1676 at the begining of the C<@_> argument list. This is a variation of
1677 continuation passing style, where the function prepended to C<@_>
1678 can be considered a continuation. It is up to C<$code> if it calls
1679 the original method or not, there is no restriction on what the
1680 C<$code> can or cannot do.
1686 It should be noted that since there is no one consistent way to define
1687 the attributes of a class in Perl 5. These methods can only work with
1688 the information given, and can not easily discover information on
1689 their own. See L<Class::MOP::Attribute> for more details.
1693 =item B<attribute_metaclass>
1695 Returns the class name of the attribute metaclass, see L<Class::MOP::Attribute>
1696 for more information on the attribute metaclasses.
1698 =item B<get_attribute_map>
1700 This returns a HASH ref of name to attribute meta-object mapping.
1702 =item B<add_attribute ($attribute_meta_object | ($attribute_name, %attribute_spec))>
1704 This stores the C<$attribute_meta_object> (or creates one from the
1705 C<$attribute_name> and C<%attribute_spec>) in the B<Class::MOP::Class>
1706 instance associated with the given class. Unlike methods, attributes
1707 within the MOP are stored as meta-information only. They will be used
1708 later to construct instances from (see C<construct_instance> above).
1709 More details about the attribute meta-objects can be found in the
1710 L<Class::MOP::Attribute> or the L<Class::MOP/The Attribute protocol>
1713 It should be noted that any accessor, reader/writer or predicate
1714 methods which the C<$attribute_meta_object> has will be installed
1715 into the class at this time.
1718 If an attribute already exists for C<$attribute_name>, the old one
1719 will be removed (as well as removing all it's accessors), and then
1722 =item B<has_attribute ($attribute_name)>
1724 Checks to see if this class has an attribute by the name of
1725 C<$attribute_name> and returns a boolean.
1727 =item B<get_attribute ($attribute_name)>
1729 Returns the attribute meta-object associated with C<$attribute_name>,
1730 if none is found, it will return undef.
1732 =item B<remove_attribute ($attribute_name)>
1734 This will remove the attribute meta-object stored at
1735 C<$attribute_name>, then return the removed attribute meta-object.
1738 Removing an attribute will only affect future instances of
1739 the class, it will not make any attempt to remove the attribute from
1740 any existing instances of the class.
1742 It should be noted that any accessor, reader/writer or predicate
1743 methods which the attribute meta-object stored at C<$attribute_name>
1744 has will be removed from the class at this time. This B<will> make
1745 these attributes somewhat inaccessable in previously created
1746 instances. But if you are crazy enough to do this at runtime, then
1747 you are crazy enough to deal with something like this :).
1749 =item B<get_attribute_list>
1751 This returns a list of attribute names which are defined in the local
1752 class. If you want a list of all applicable attributes for a class,
1753 use the C<compute_all_applicable_attributes> method.
1755 =item B<compute_all_applicable_attributes>
1757 =item B<get_all_attributes>
1759 This will traverse the inheritance heirachy and return a list of all
1760 the applicable L<Class::MOP::Attribute> objects for this class.
1762 C<get_all_attributes> is an alias for consistency with C<get_all_methods>.
1764 =item B<find_attribute_by_name ($attr_name)>
1766 This method will traverse the inheritance heirachy and find the
1767 first attribute whose name matches C<$attr_name>, then return it.
1768 It will return undef if nothing is found.
1772 =head2 Class Immutability
1776 =item B<make_immutable (%options)>
1778 This method will invoke a tranforamtion upon the class which will
1779 make it immutable. Details of this transformation can be found in
1780 the L<Class::MOP::Immutable> documentation.
1782 =item B<make_mutable>
1784 This method will reverse tranforamtion upon the class which
1787 =item B<get_immutable_transformer>
1789 Return a transformer suitable for making this class immutable or, if this
1790 class is immutable, the transformer used to make it immutable.
1792 =item B<get_immutable_options>
1794 If the class is immutable, return the options used to make it immutable.
1796 =item B<create_immutable_transformer>
1798 Create a transformer suitable for making this class immutable
1804 Stevan Little E<lt>stevan@iinteractive.comE<gt>
1806 =head1 COPYRIGHT AND LICENSE
1808 Copyright 2006-2008 by Infinity Interactive, Inc.
1810 L<http://www.iinteractive.com>
1812 This library is free software; you can redistribute it and/or modify
1813 it under the same terms as Perl itself.