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 my ($serial_id) = ($self->name =~ /^$ANON_CLASS_PREFIX(\d+)/);
227 foreach my $key (keys %{$ANON_CLASS_PREFIX . $serial_id}) {
228 delete ${$ANON_CLASS_PREFIX . $serial_id}{$key};
230 delete ${'main::' . $ANON_CLASS_PREFIX}{$serial_id . '::'};
235 # creating classes with MOP ...
238 my ( $class, @args ) = @_;
240 unshift @args, 'package' if @args % 2 == 1;
242 my (%options) = @args;
243 my $package_name = $options{package};
245 (defined $package_name && $package_name)
246 || confess "You must pass a package name";
248 (ref $options{superclasses} eq 'ARRAY')
249 || confess "You must pass an ARRAY ref of superclasses"
250 if exists $options{superclasses};
252 (ref $options{attributes} eq 'ARRAY')
253 || confess "You must pass an ARRAY ref of attributes"
254 if exists $options{attributes};
256 (ref $options{methods} eq 'HASH')
257 || confess "You must pass an HASH ref of methods"
258 if exists $options{methods};
260 my $code = "package $package_name;";
261 $code .= "\$$package_name\:\:VERSION = '" . $options{version} . "';"
262 if exists $options{version};
263 $code .= "\$$package_name\:\:AUTHORITY = '" . $options{authority} . "';"
264 if exists $options{authority};
267 confess "creation of $package_name failed : $@" if $@;
269 my $meta = $class->initialize($package_name);
272 $meta->add_method('meta' => sub {
273 $class->initialize(ref($_[0]) || $_[0]);
276 $meta->superclasses(@{$options{superclasses}})
277 if exists $options{superclasses};
279 # process attributes first, so that they can
280 # install accessors, but locally defined methods
281 # can then overwrite them. It is maybe a little odd, but
282 # I think this should be the order of things.
283 if (exists $options{attributes}) {
284 foreach my $attr (@{$options{attributes}}) {
285 $meta->add_attribute($attr);
288 if (exists $options{methods}) {
289 foreach my $method_name (keys %{$options{methods}}) {
290 $meta->add_method($method_name, $options{methods}->{$method_name});
299 # all these attribute readers will be bootstrapped
300 # away in the Class::MOP bootstrap section
302 sub get_attribute_map { $_[0]->{'attributes'} }
303 sub attribute_metaclass { $_[0]->{'attribute_metaclass'} }
304 sub method_metaclass { $_[0]->{'method_metaclass'} }
305 sub instance_metaclass { $_[0]->{'instance_metaclass'} }
308 # this is a prime canidate for conversion to XS
312 my $current = Class::MOP::check_package_cache_flag($self->name);
314 if (defined $self->{'_package_cache_flag'} && $self->{'_package_cache_flag'} == $current) {
315 return $self->{'methods'} ||= {};
318 $self->{_package_cache_flag} = $current;
320 my $map = $self->{'methods'} ||= {};
322 my $class_name = $self->name;
323 my $method_metaclass = $self->method_metaclass;
325 my %all_code = $self->get_all_package_symbols('CODE');
327 foreach my $symbol (keys %all_code) {
328 my $code = $all_code{$symbol};
330 next if exists $map->{$symbol} &&
331 defined $map->{$symbol} &&
332 $map->{$symbol}->body == $code;
334 my ($pkg, $name) = Class::MOP::get_code_info($code);
337 # in 5.10 constant.pm the constants show up
338 # as being in the right package, but in pre-5.10
339 # they show up as constant::__ANON__ so we
340 # make an exception here to be sure that things
341 # work as expected in both.
343 unless ($pkg eq 'constant' && $name eq '__ANON__') {
344 next if ($pkg || '') ne $class_name ||
345 (($name || '') ne '__ANON__' && ($pkg || '') ne $class_name);
348 $map->{$symbol} = $method_metaclass->wrap(
350 associated_metaclass => $self,
351 package_name => $class_name,
359 # Instance Construction & Cloning
365 # we need to protect the integrity of the
366 # Class::MOP::Class singletons here, so we
367 # delegate this to &construct_class_instance
368 # which will deal with the singletons
369 return $class->construct_class_instance(@_)
370 if $class->name->isa('Class::MOP::Class');
371 return $class->construct_instance(@_);
374 sub construct_instance {
376 my $params = @_ == 1 ? $_[0] : {@_};
377 my $meta_instance = $class->get_meta_instance();
378 my $instance = $meta_instance->create_instance();
379 foreach my $attr ($class->compute_all_applicable_attributes()) {
380 $attr->initialize_instance_slot($meta_instance, $instance, $params);
383 # this will only work for a HASH instance type
384 if ($class->is_anon_class) {
385 (Scalar::Util::reftype($instance) eq 'HASH')
386 || confess "Currently only HASH based instances are supported with instance of anon-classes";
388 # At some point we should make this official
389 # as a reserved slot name, but right now I am
390 # going to keep it here.
391 # my $RESERVED_MOP_SLOT = '__MOP__';
392 $instance->{'__MOP__'} = $class;
398 sub get_meta_instance {
400 $self->{'_meta_instance'} ||= $self->create_meta_instance();
403 sub create_meta_instance {
406 my $instance = $self->instance_metaclass->new(
407 associated_metaclass => $self,
408 attributes => [ $self->compute_all_applicable_attributes() ],
411 $self->add_meta_instance_dependencies()
412 if $instance->is_dependent_on_superclasses();
419 my $instance = shift;
420 (blessed($instance) && $instance->isa($class->name))
421 || confess "You must pass an instance of the metaclass (" . (ref $class ? $class->name : $class) . "), not ($instance)";
424 # we need to protect the integrity of the
425 # Class::MOP::Class singletons here, they
426 # should not be cloned.
427 return $instance if $instance->isa('Class::MOP::Class');
428 $class->clone_instance($instance, @_);
432 my ($class, $instance, %params) = @_;
434 || confess "You can only clone instances, ($instance) is not a blessed instance";
435 my $meta_instance = $class->get_meta_instance();
436 my $clone = $meta_instance->clone_instance($instance);
437 foreach my $attr ($class->compute_all_applicable_attributes()) {
438 if ( defined( my $init_arg = $attr->init_arg ) ) {
439 if (exists $params{$init_arg}) {
440 $attr->set_value($clone, $params{$init_arg});
447 sub rebless_instance {
448 my ($self, $instance, %params) = @_;
451 if ($instance->can('meta')) {
452 ($instance->meta->isa('Class::MOP::Class'))
453 || confess 'Cannot rebless instance if ->meta is not an instance of Class::MOP::Class';
454 $old_metaclass = $instance->meta;
457 $old_metaclass = $self->initialize(ref($instance));
460 my $meta_instance = $self->get_meta_instance();
462 $self->name->isa($old_metaclass->name)
463 || confess "You may rebless only into a subclass of (". $old_metaclass->name ."), of which (". $self->name .") isn't.";
466 $meta_instance->rebless_instance_structure($instance, $self);
468 foreach my $attr ( $self->compute_all_applicable_attributes ) {
469 if ( $attr->has_value($instance) ) {
470 if ( defined( my $init_arg = $attr->init_arg ) ) {
471 $params{$init_arg} = $attr->get_value($instance)
472 unless exists $params{$init_arg};
475 $attr->set_value($instance, $attr->get_value($instance));
480 foreach my $attr ($self->compute_all_applicable_attributes) {
481 $attr->initialize_instance_slot($meta_instance, $instance, \%params);
491 my $var_spec = { sigil => '@', type => 'ARRAY', name => 'ISA' };
494 @{$self->get_package_symbol($var_spec)} = @supers;
496 # we need to check the metaclass
497 # compatibility here so that we can
498 # be sure that the superclass is
499 # not potentially creating an issues
500 # we don't know about
502 $self->check_metaclass_compatibility();
503 $self->update_meta_instance_dependencies();
505 @{$self->get_package_symbol($var_spec)};
511 my $super_class = $self->name;
513 if ( Class::MOP::HAVE_ISAREV() ) {
514 return @{ $super_class->mro::get_isarev() };
518 my $find_derived_classes;
519 $find_derived_classes = sub {
520 my ($outer_class) = @_;
522 my $symbol_table_hashref = do { no strict 'refs'; \%{"${outer_class}::"} };
525 for my $symbol ( keys %$symbol_table_hashref ) {
526 next SYMBOL if $symbol !~ /\A (\w+):: \z/x;
527 my $inner_class = $1;
529 next SYMBOL if $inner_class eq 'SUPER'; # skip '*::SUPER'
533 ? "${outer_class}::$inner_class"
536 if ( $class->isa($super_class) and $class ne $super_class ) {
537 push @derived_classes, $class;
540 next SYMBOL if $class eq 'main'; # skip 'main::*'
542 $find_derived_classes->($class);
546 my $root_class = q{};
547 $find_derived_classes->($root_class);
549 undef $find_derived_classes;
551 @derived_classes = sort { $a->isa($b) ? 1 : $b->isa($a) ? -1 : 0 } @derived_classes;
553 return @derived_classes;
559 return @{ mro::get_linear_isa( (shift)->name ) };
562 sub class_precedence_list {
564 my $name = $self->name;
566 unless (Class::MOP::IS_RUNNING_ON_5_10()) {
568 # We need to check for circular inheritance here
569 # if we are are not on 5.10, cause 5.8 detects it
570 # late. This will do nothing if all is well, and
571 # blow up otherwise. Yes, it's an ugly hack, better
572 # suggestions are welcome.
574 ($name || return)->isa('This is a test for circular inheritance')
577 # if our mro is c3, we can
578 # just grab the linear_isa
579 if (mro::get_mro($name) eq 'c3') {
580 return @{ mro::get_linear_isa($name) }
584 # we can't grab the linear_isa for dfs
585 # since it has all the duplicates
590 $self->initialize($_)->class_precedence_list()
591 } $self->superclasses()
598 sub wrap_method_body {
599 my ( $self, %args ) = @_;
601 ('CODE' eq ref $args{body})
602 || confess "Your code block must be a CODE reference";
604 $self->method_metaclass->wrap(
605 package_name => $self->name,
611 my ($self, $method_name, $method) = @_;
612 (defined $method_name && $method_name)
613 || confess "You must define a method name";
616 if (blessed($method)) {
617 $body = $method->body;
618 if ($method->package_name ne $self->name) {
619 $method = $method->clone(
620 package_name => $self->name,
622 ) if $method->can('clone');
627 $method = $self->wrap_method_body( body => $body, name => $method_name );
630 $method->attach_to_class($self);
632 $self->get_method_map->{$method_name} = $method;
634 my $full_method_name = ($self->name . '::' . $method_name);
635 $self->add_package_symbol(
636 { sigil => '&', type => 'CODE', name => $method_name },
637 Class::MOP::subname($full_method_name => $body)
640 $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
644 my $fetch_and_prepare_method = sub {
645 my ($self, $method_name) = @_;
647 my $method = $self->get_method($method_name);
648 # if we dont have local ...
650 # try to find the next method
651 $method = $self->find_next_method_by_name($method_name);
652 # die if it does not exist
654 || confess "The method '$method_name' is not found in the inheritance hierarchy for class " . $self->name;
655 # and now make sure to wrap it
656 # even if it is already wrapped
657 # because we need a new sub ref
658 $method = Class::MOP::Method::Wrapped->wrap($method);
661 # now make sure we wrap it properly
662 $method = Class::MOP::Method::Wrapped->wrap($method)
663 unless $method->isa('Class::MOP::Method::Wrapped');
665 $self->add_method($method_name => $method);
669 sub add_before_method_modifier {
670 my ($self, $method_name, $method_modifier) = @_;
671 (defined $method_name && $method_name)
672 || confess "You must pass in a method name";
673 my $method = $fetch_and_prepare_method->($self, $method_name);
674 $method->add_before_modifier(
675 Class::MOP::subname(':before' => $method_modifier)
679 sub add_after_method_modifier {
680 my ($self, $method_name, $method_modifier) = @_;
681 (defined $method_name && $method_name)
682 || confess "You must pass in a method name";
683 my $method = $fetch_and_prepare_method->($self, $method_name);
684 $method->add_after_modifier(
685 Class::MOP::subname(':after' => $method_modifier)
689 sub add_around_method_modifier {
690 my ($self, $method_name, $method_modifier) = @_;
691 (defined $method_name && $method_name)
692 || confess "You must pass in a method name";
693 my $method = $fetch_and_prepare_method->($self, $method_name);
694 $method->add_around_modifier(
695 Class::MOP::subname(':around' => $method_modifier)
700 # the methods above used to be named like this:
701 # ${pkg}::${method}:(before|after|around)
702 # but this proved problematic when using one modifier
703 # to wrap multiple methods (something which is likely
704 # to happen pretty regularly IMO). So instead of naming
705 # it like this, I have chosen to just name them purely
706 # with their modifier names, like so:
707 # :(before|after|around)
708 # The fact is that in a stack trace, it will be fairly
709 # evident from the context what method they are attached
710 # to, and so don't need the fully qualified name.
716 $self->add_method(@_);
720 my ($self, $method_name) = @_;
721 (defined $method_name && $method_name)
722 || confess "You must define a method name";
724 exists $self->get_method_map->{$method_name};
728 my ($self, $method_name) = @_;
729 (defined $method_name && $method_name)
730 || confess "You must define a method name";
733 # I don't really need this here, because
734 # if the method_map is missing a key it
735 # will just return undef for me now
736 # return unless $self->has_method($method_name);
738 return $self->get_method_map->{$method_name};
742 my ($self, $method_name) = @_;
743 (defined $method_name && $method_name)
744 || confess "You must define a method name";
746 my $removed_method = delete $self->get_method_map->{$method_name};
748 $self->remove_package_symbol(
749 { sigil => '&', type => 'CODE', name => $method_name }
752 $removed_method->detach_from_class if $removed_method;
754 $self->update_package_cache_flag; # still valid, since we just removed the method from the map
756 return $removed_method;
759 sub get_method_list {
761 keys %{$self->get_method_map};
764 sub find_method_by_name {
765 my ($self, $method_name) = @_;
766 (defined $method_name && $method_name)
767 || confess "You must define a method name to find";
768 foreach my $class ($self->linearized_isa) {
769 # fetch the meta-class ...
770 my $meta = $self->initialize($class);
771 return $meta->get_method($method_name)
772 if $meta->has_method($method_name);
777 sub get_all_methods {
779 my %methods = map { %{ $self->initialize($_)->get_method_map } } reverse $self->linearized_isa;
780 return values %methods;
784 sub compute_all_applicable_methods {
788 class => $_->package_name,
789 code => $_, # sigh, overloading
791 } shift->get_all_methods(@_);
794 sub find_all_methods_by_name {
795 my ($self, $method_name) = @_;
796 (defined $method_name && $method_name)
797 || confess "You must define a method name to find";
799 foreach my $class ($self->linearized_isa) {
800 # fetch the meta-class ...
801 my $meta = $self->initialize($class);
803 name => $method_name,
805 code => $meta->get_method($method_name)
806 } if $meta->has_method($method_name);
811 sub find_next_method_by_name {
812 my ($self, $method_name) = @_;
813 (defined $method_name && $method_name)
814 || confess "You must define a method name to find";
815 my @cpl = $self->linearized_isa;
816 shift @cpl; # discard ourselves
817 foreach my $class (@cpl) {
818 # fetch the meta-class ...
819 my $meta = $self->initialize($class);
820 return $meta->get_method($method_name)
821 if $meta->has_method($method_name);
830 # either we have an attribute object already
831 # or we need to create one from the args provided
832 my $attribute = blessed($_[0]) ? $_[0] : $self->attribute_metaclass->new(@_);
833 # make sure it is derived from the correct type though
834 ($attribute->isa('Class::MOP::Attribute'))
835 || confess "Your attribute must be an instance of Class::MOP::Attribute (or a subclass)";
837 # first we attach our new attribute
838 # because it might need certain information
839 # about the class which it is attached to
840 $attribute->attach_to_class($self);
842 # then we remove attributes of a conflicting
843 # name here so that we can properly detach
844 # the old attr object, and remove any
845 # accessors it would have generated
846 if ( $self->has_attribute($attribute->name) ) {
847 $self->remove_attribute($attribute->name);
849 $self->invalidate_meta_instances();
852 # then onto installing the new accessors
853 $self->get_attribute_map->{$attribute->name} = $attribute;
855 # invalidate package flag here
856 my $e = do { local $@; eval { $attribute->install_accessors() }; $@ };
858 $self->remove_attribute($attribute->name);
865 sub update_meta_instance_dependencies {
868 if ( $self->{meta_instance_dependencies} ) {
869 return $self->add_meta_instance_dependencies;
873 sub add_meta_instance_dependencies {
876 $self->remove_meta_instance_depdendencies;
878 my @attrs = $self->compute_all_applicable_attributes();
881 my @classes = grep { not $seen{$_->name}++ } map { $_->associated_class } @attrs;
883 foreach my $class ( @classes ) {
884 $class->add_dependent_meta_instance($self);
887 $self->{meta_instance_dependencies} = \@classes;
890 sub remove_meta_instance_depdendencies {
893 if ( my $classes = delete $self->{meta_instance_dependencies} ) {
894 foreach my $class ( @$classes ) {
895 $class->remove_dependent_meta_instance($self);
905 sub add_dependent_meta_instance {
906 my ( $self, $metaclass ) = @_;
907 push @{ $self->{dependent_meta_instances} }, $metaclass;
910 sub remove_dependent_meta_instance {
911 my ( $self, $metaclass ) = @_;
912 my $name = $metaclass->name;
913 @$_ = grep { $_->name ne $name } @$_ for $self->{dependent_meta_instances};
916 sub invalidate_meta_instances {
918 $_->invalidate_meta_instance() for $self, @{ $self->{dependent_meta_instances} };
921 sub invalidate_meta_instance {
923 undef $self->{_meta_instance};
927 my ($self, $attribute_name) = @_;
928 (defined $attribute_name && $attribute_name)
929 || confess "You must define an attribute name";
930 exists $self->get_attribute_map->{$attribute_name};
934 my ($self, $attribute_name) = @_;
935 (defined $attribute_name && $attribute_name)
936 || confess "You must define an attribute name";
937 return $self->get_attribute_map->{$attribute_name}
939 # this will return undef anyway, so no need ...
940 # if $self->has_attribute($attribute_name);
944 sub remove_attribute {
945 my ($self, $attribute_name) = @_;
946 (defined $attribute_name && $attribute_name)
947 || confess "You must define an attribute name";
948 my $removed_attribute = $self->get_attribute_map->{$attribute_name};
949 return unless defined $removed_attribute;
950 delete $self->get_attribute_map->{$attribute_name};
951 $self->invalidate_meta_instances();
952 $removed_attribute->remove_accessors();
953 $removed_attribute->detach_from_class();
954 return $removed_attribute;
957 sub get_attribute_list {
959 keys %{$self->get_attribute_map};
962 sub get_all_attributes {
963 shift->compute_all_applicable_attributes(@_);
966 sub compute_all_applicable_attributes {
968 my %attrs = map { %{ $self->initialize($_)->get_attribute_map } } reverse $self->linearized_isa;
969 return values %attrs;
972 sub find_attribute_by_name {
973 my ($self, $attr_name) = @_;
974 foreach my $class ($self->linearized_isa) {
975 # fetch the meta-class ...
976 my $meta = $self->initialize($class);
977 return $meta->get_attribute($attr_name)
978 if $meta->has_attribute($attr_name);
983 # check if we can reinitialize
987 # if any local attr is defined
988 return if $self->get_attribute_list;
990 # or any non-declared methods
991 if ( my @methods = values %{ $self->get_method_map } ) {
992 my $metaclass = $self->method_metaclass;
993 foreach my $method ( @methods ) {
994 return if $method->isa("Class::MOP::Method::Generated");
995 # FIXME do we need to enforce this too? return unless $method->isa($metaclass);
1004 sub is_mutable { 1 }
1005 sub is_immutable { 0 }
1008 # Why I changed this (groditi)
1009 # - One Metaclass may have many Classes through many Metaclass instances
1010 # - One Metaclass should only have one Immutable Transformer instance
1011 # - Each Class may have different Immutabilizing options
1012 # - Therefore each Metaclass instance may have different Immutabilizing options
1013 # - We need to store one Immutable Transformer instance per Metaclass
1014 # - We need to store one set of Immutable Transformer options per Class
1015 # - Upon make_mutable we may delete the Immutabilizing options
1016 # - We could clean the immutable Transformer instance when there is no more
1017 # immutable Classes of that type, but we can also keep it in case
1018 # another class with this same Metaclass becomes immutable. It is a case
1019 # of trading of storing an instance to avoid unnecessary instantiations of
1020 # Immutable Transformers. You may view this as a memory leak, however
1021 # Because we have few Metaclasses, in practice it seems acceptable
1022 # - To allow Immutable Transformers instances to be cleaned up we could weaken
1023 # the reference stored in $IMMUTABLE_TRANSFORMERS{$class} and ||= should DWIM
1027 my %IMMUTABLE_TRANSFORMERS;
1028 my %IMMUTABLE_OPTIONS;
1030 sub get_immutable_options {
1032 return if $self->is_mutable;
1033 confess "unable to find immutabilizing options"
1034 unless exists $IMMUTABLE_OPTIONS{$self->name};
1035 my %options = %{$IMMUTABLE_OPTIONS{$self->name}};
1036 delete $options{IMMUTABLE_TRANSFORMER};
1040 sub get_immutable_transformer {
1042 if( $self->is_mutable ){
1043 my $class = ref $self || $self;
1044 return $IMMUTABLE_TRANSFORMERS{$class} ||= $self->create_immutable_transformer;
1046 confess "unable to find transformer for immutable class"
1047 unless exists $IMMUTABLE_OPTIONS{$self->name};
1048 return $IMMUTABLE_OPTIONS{$self->name}->{IMMUTABLE_TRANSFORMER};
1051 sub make_immutable {
1055 my $transformer = $self->get_immutable_transformer;
1056 $transformer->make_metaclass_immutable($self, \%options);
1057 $IMMUTABLE_OPTIONS{$self->name} =
1058 { %options, IMMUTABLE_TRANSFORMER => $transformer };
1060 if( exists $options{debug} && $options{debug} ){
1061 print STDERR "# of Metaclass options: ", keys %IMMUTABLE_OPTIONS;
1062 print STDERR "# of Immutable transformers: ", keys %IMMUTABLE_TRANSFORMERS;
1070 return if $self->is_mutable;
1071 my $options = delete $IMMUTABLE_OPTIONS{$self->name};
1072 confess "unable to find immutabilizing options" unless ref $options;
1073 my $transformer = delete $options->{IMMUTABLE_TRANSFORMER};
1074 $transformer->make_metaclass_mutable($self, $options);
1079 sub create_immutable_transformer {
1081 my $class = Class::MOP::Immutable->new($self, {
1082 read_only => [qw/superclasses/],
1089 remove_package_symbol
1092 class_precedence_list => 'ARRAY',
1093 linearized_isa => 'ARRAY', # FIXME perl 5.10 memoizes this on its own, no need?
1094 get_all_methods => 'ARRAY',
1095 #get_all_attributes => 'ARRAY', # it's an alias, no need, but maybe in the future
1096 compute_all_applicable_attributes => 'ARRAY',
1097 get_meta_instance => 'SCALAR',
1098 get_method_map => 'SCALAR',
1101 # this is ugly, but so are typeglobs,
1102 # so whattayahgonnadoboutit
1105 add_package_symbol => sub {
1106 my $original = shift;
1107 confess "Cannot add package symbols to an immutable metaclass"
1108 unless (caller(2))[3] eq 'Class::MOP::Package::get_package_symbol';
1110 # This is a workaround for a bug in 5.8.1 which thinks that
1111 # goto $original->body
1112 # is trying to go to a label
1113 my $body = $original->body;
1129 Class::MOP::Class - Class Meta Object
1133 # assuming that class Foo
1134 # has been defined, you can
1136 # use this for introspection ...
1138 # add a method to Foo ...
1139 Foo->meta->add_method('bar' => sub { ... })
1141 # get a list of all the classes searched
1142 # the method dispatcher in the correct order
1143 Foo->meta->class_precedence_list()
1145 # remove a method from Foo
1146 Foo->meta->remove_method('bar');
1148 # or use this to actually create classes ...
1150 Class::MOP::Class->create('Bar' => (
1152 superclasses => [ 'Foo' ],
1154 Class::MOP:::Attribute->new('$bar'),
1155 Class::MOP:::Attribute->new('$baz'),
1158 calculate_bar => sub { ... },
1159 construct_baz => sub { ... }
1165 This is the largest and currently most complex part of the Perl 5
1166 meta-object protocol. It controls the introspection and
1167 manipulation of Perl 5 classes (and it can create them too). The
1168 best way to understand what this module can do, is to read the
1169 documentation for each of it's methods.
1173 =head2 Self Introspection
1179 This will return a B<Class::MOP::Class> instance which is related
1180 to this class. Thereby allowing B<Class::MOP::Class> to actually
1183 As with B<Class::MOP::Attribute>, B<Class::MOP> will actually
1184 bootstrap this module by installing a number of attribute meta-objects
1185 into it's metaclass. This will allow this class to reap all the benifits
1186 of the MOP when subclassing it.
1190 =head2 Class construction
1192 These methods will handle creating B<Class::MOP::Class> objects,
1193 which can be used to both create new classes, and analyze
1194 pre-existing classes.
1196 This module will internally store references to all the instances
1197 you create with these methods, so that they do not need to be
1198 created any more than nessecary. Basically, they are singletons.
1202 =item B<create ($package_name,
1203 version =E<gt> ?$version,
1204 authority =E<gt> ?$authority,
1205 superclasses =E<gt> ?@superclasses,
1206 methods =E<gt> ?%methods,
1207 attributes =E<gt> ?%attributes)>
1209 This returns a B<Class::MOP::Class> object, bringing the specified
1210 C<$package_name> into existence and adding any of the C<$version>,
1211 C<$authority>, C<@superclasses>, C<%methods> and C<%attributes> to
1214 =item B<create_anon_class (superclasses =E<gt> ?@superclasses,
1215 methods =E<gt> ?%methods,
1216 attributes =E<gt> ?%attributes)>
1218 This will create an anonymous class, it works much like C<create> but
1219 it does not need a C<$package_name>. Instead it will create a suitably
1220 unique package name for you to stash things into.
1222 On very important distinction is that anon classes are destroyed once
1223 the metaclass they are attached to goes out of scope. In the DESTROY
1224 method, the created package will be removed from the symbol table.
1226 It is also worth noting that any instances created with an anon-class
1227 will keep a special reference to the anon-meta which will prevent the
1228 anon-class from going out of scope until all instances of it have also
1229 been destroyed. This however only works for HASH based instance types,
1230 as we use a special reserved slot (C<__MOP__>) to store this.
1232 =item B<initialize ($package_name, %options)>
1234 This initializes and returns returns a B<Class::MOP::Class> object
1235 for a given a C<$package_name>.
1237 =item B<construct_class_instance (%options)>
1239 This will construct an instance of B<Class::MOP::Class>, it is
1240 here so that we can actually "tie the knot" for B<Class::MOP::Class>
1241 to use C<construct_instance> once all the bootstrapping is done. This
1242 method is used internally by C<initialize> and should never be called
1243 from outside of that method really.
1245 =item B<check_metaclass_compatibility>
1247 This method is called as the very last thing in the
1248 C<construct_class_instance> method. This will check that the
1249 metaclass you are creating is compatible with the metaclasses of all
1250 your ancestors. For more inforamtion about metaclass compatibility
1251 see the C<About Metaclass compatibility> section in L<Class::MOP>.
1253 =item B<update_package_cache_flag>
1255 This will reset the package cache flag for this particular metaclass
1256 it is basically the value of the C<Class::MOP::get_package_cache_flag>
1257 function. This is very rarely needed from outside of C<Class::MOP::Class>
1258 but in some cases you might want to use it, so it is here.
1260 =item B<reset_package_cache_flag>
1262 Clears the package cache flag to announce to the internals that we need
1263 to rebuild the method map.
1265 =item B<add_meta_instance_dependencies>
1267 Registers this class as dependent on its superclasses.
1269 Only superclasses from which this class inherits attributes will be added.
1271 =item B<remove_meta_instance_depdendencies>
1273 Unregisters this class from its superclasses.
1275 =item B<update_meta_instance_dependencies>
1277 Reregisters if necessary.
1279 =item B<add_dependent_meta_instance> $metaclass
1281 Registers the class as having a meta instance dependent on this class.
1283 =item B<remove_dependent_meta_instance> $metaclass
1285 Remove the class from the list of dependent classes.
1287 =item B<invalidate_meta_instances>
1289 Clears the cached meta instance for this metaclass and all of the registered
1290 classes with dependent meta instances.
1292 Called by C<add_attribute> and C<remove_attribute> to recalculate the attribute
1295 =item B<invalidate_meta_instance>
1297 Used by C<invalidate_meta_instances>.
1301 =head2 Object instance construction and cloning
1303 These methods are B<entirely optional>, it is up to you whether you want
1308 =item B<instance_metaclass>
1310 Returns the class name of the instance metaclass, see L<Class::MOP::Instance>
1311 for more information on the instance metaclasses.
1313 =item B<get_meta_instance>
1315 Returns an instance of L<Class::MOP::Instance> to be used in the construction
1316 of a new instance of the class.
1318 =item B<create_meta_instance>
1320 Called by C<get_meta_instance> if necessary.
1322 =item B<new_object (%params)>
1324 This is a convience method for creating a new object of the class, and
1325 blessing it into the appropriate package as well. Ideally your class
1326 would call a C<new> this method like so:
1329 my ($class, %param) = @_;
1330 $class->meta->new_object(%params);
1333 =item B<construct_instance (%params)>
1335 This method is used to construct an instance structure suitable for
1336 C<bless>-ing into your package of choice. It works in conjunction
1337 with the Attribute protocol to collect all applicable attributes.
1339 This will construct and instance using a HASH ref as storage
1340 (currently only HASH references are supported). This will collect all
1341 the applicable attributes and layout out the fields in the HASH ref,
1342 it will then initialize them using either use the corresponding key
1343 in C<%params> or any default value or initializer found in the
1344 attribute meta-object.
1346 =item B<clone_object ($instance, %params)>
1348 This is a convience method for cloning an object instance, then
1349 blessing it into the appropriate package. This method will call
1350 C<clone_instance>, which performs a shallow copy of the object,
1351 see that methods documentation for more details. Ideally your
1352 class would call a C<clone> this method like so:
1354 sub MyClass::clone {
1355 my ($self, %param) = @_;
1356 $self->meta->clone_object($self, %params);
1359 =item B<clone_instance($instance, %params)>
1361 This method is a compliment of C<construct_instance> (which means if
1362 you override C<construct_instance>, you need to override this one too),
1363 and clones the instance shallowly.
1365 The cloned structure returned is (like with C<construct_instance>) an
1366 unC<bless>ed HASH reference, it is your responsibility to then bless
1367 this cloned structure into the right class (which C<clone_object> will
1370 As of 0.11, this method will clone the C<$instance> structure shallowly,
1371 as opposed to the deep cloning implemented in prior versions. After much
1372 thought, research and discussion, I have decided that anything but basic
1373 shallow cloning is outside the scope of the meta-object protocol. I
1374 think Yuval "nothingmuch" Kogman put it best when he said that cloning
1375 is too I<context-specific> to be part of the MOP.
1377 =item B<rebless_instance($instance, ?%params)>
1379 This will change the class of C<$instance> to the class of the invoking
1380 C<Class::MOP::Class>. You may only rebless the instance to a subclass of
1381 itself. You may pass in optional C<%params> which are like constructor
1382 params and will override anything already defined in the instance.
1386 =head2 Informational
1388 These are a few predicate methods for asking information about the class.
1392 =item B<is_anon_class>
1394 This returns true if the class is a C<Class::MOP::Class> created anon class.
1398 This returns true if the class is still mutable.
1400 =item B<is_immutable>
1402 This returns true if the class has been made immutable.
1404 =item B<is_pristine>
1406 Checks whether the class has any data that will be lost if C<reinitialize> is
1411 =head2 Inheritance Relationships
1415 =item B<superclasses (?@superclasses)>
1417 This is a read-write attribute which represents the superclass
1418 relationships of the class the B<Class::MOP::Class> instance is
1419 associated with. Basically, it can get and set the C<@ISA> for you.
1421 =item B<class_precedence_list>
1423 This computes the a list of all the class's ancestors in the same order
1424 in which method dispatch will be done. This is similair to what
1425 B<Class::ISA::super_path> does, but we don't remove duplicate names.
1427 =item B<linearized_isa>
1429 This returns a list based on C<class_precedence_list> but with all
1434 This returns a list of subclasses for this class.
1442 =item B<get_method_map>
1444 Returns a HASH ref of name to CODE reference mapping for this class.
1446 =item B<method_metaclass>
1448 Returns the class name of the method metaclass, see L<Class::MOP::Method>
1449 for more information on the method metaclasses.
1451 =item B<wrap_method_body(%attrs)>
1453 Wrap a code ref (C<$attrs{body>) with C<method_metaclass>.
1455 =item B<add_method ($method_name, $method, %attrs)>
1457 This will take a C<$method_name> and CODE reference or meta method
1458 objectand install it into the class's package.
1460 You are strongly encouraged to pass a meta method object instead of a
1461 code reference. If you do so, that object gets stored as part of the
1462 class's method map, providing more useful information about the method
1465 When you provide a method object, this method will clone that object
1466 if the object's package name does not match the class name. This lets
1467 us track the original source of any methods added from other classes
1468 (notably Moose roles).
1471 This does absolutely nothing special to C<$method>
1472 other than use B<Sub::Name> to make sure it is tagged with the
1473 correct name, and therefore show up correctly in stack traces and
1476 =item B<has_method ($method_name)>
1478 This just provides a simple way to check if the class implements
1479 a specific C<$method_name>. It will I<not> however, attempt to check
1480 if the class inherits the method (use C<UNIVERSAL::can> for that).
1482 This will correctly handle functions defined outside of the package
1483 that use a fully qualified name (C<sub Package::name { ... }>).
1485 This will correctly handle functions renamed with B<Sub::Name> and
1486 installed using the symbol tables. However, if you are naming the
1487 subroutine outside of the package scope, you must use the fully
1488 qualified name, including the package name, for C<has_method> to
1489 correctly identify it.
1491 This will attempt to correctly ignore functions imported from other
1492 packages using B<Exporter>. It breaks down if the function imported
1493 is an C<__ANON__> sub (such as with C<use constant>), which very well
1494 may be a valid method being applied to the class.
1496 In short, this method cannot always be trusted to determine if the
1497 C<$method_name> is actually a method. However, it will DWIM about
1498 90% of the time, so it's a small trade off I think.
1500 =item B<get_method ($method_name)>
1502 This will return a Class::MOP::Method instance related to the specified
1503 C<$method_name>, or return undef if that method does not exist.
1505 The Class::MOP::Method is codifiable, so you can use it like a normal
1506 CODE reference, see L<Class::MOP::Method> for more information.
1508 =item B<find_method_by_name ($method_name)>
1510 This will return a CODE reference of the specified C<$method_name>,
1511 or return undef if that method does not exist.
1513 Unlike C<get_method> this will also look in the superclasses.
1515 =item B<remove_method ($method_name)>
1517 This will attempt to remove a given C<$method_name> from the class.
1518 It will return the CODE reference that it has removed, and will
1519 attempt to use B<Sub::Name> to clear the methods associated name.
1521 =item B<get_method_list>
1523 This will return a list of method names for all I<locally> defined
1524 methods. It does B<not> provide a list of all applicable methods,
1525 including any inherited ones. If you want a list of all applicable
1526 methods, use the C<compute_all_applicable_methods> method.
1528 =item B<get_all_methods>
1530 This will traverse the inheritance heirachy and return a list of all
1531 the applicable L<Class::MOP::Method> objects for this class.
1533 =item B<compute_all_applicable_methods>
1537 This method returns a list of hashes describing the all the methods of the
1540 Use L<get_all_methods>, which is easier/better/faster. This method predates
1541 L<Class::MOP::Method>.
1543 =item B<find_all_methods_by_name ($method_name)>
1545 This will traverse the inheritence hierarchy and locate all methods
1546 with a given C<$method_name>. Similar to
1547 C<compute_all_applicable_methods> it returns a list of HASH references
1548 with the following information; method name (which will always be the
1549 same as C<$method_name>), the name of the class in which the method
1550 lives and a CODE reference for the actual method.
1552 The list of methods produced is a distinct list, meaning there are no
1553 duplicates in it. This is especially useful for things like object
1554 initialization and destruction where you only want the method called
1555 once, and in the correct order.
1557 =item B<find_next_method_by_name ($method_name)>
1559 This will return the first method to match a given C<$method_name> in
1560 the superclasses, this is basically equivalent to calling
1561 C<SUPER::$method_name>, but it can be dispatched at runtime.
1563 =item B<alias_method ($method_name, $method)>
1565 B<NOTE>: This method is now deprecated. Just use C<add_method>
1570 =head2 Method Modifiers
1572 Method modifiers are a concept borrowed from CLOS, in which a method
1573 can be wrapped with I<before>, I<after> and I<around> method modifiers
1574 that will be called everytime the method is called.
1576 =head3 How method modifiers work?
1578 Method modifiers work by wrapping the original method and then replacing
1579 it in the classes symbol table. The wrappers will handle calling all the
1580 modifiers in the appropariate orders and preserving the calling context
1581 for the original method.
1583 Each method modifier serves a particular purpose, which may not be
1584 obvious to users of other method wrapping modules. To start with, the
1585 return values of I<before> and I<after> modifiers are ignored. This is
1586 because thier purpose is B<not> to filter the input and output of the
1587 primary method (this is done with an I<around> modifier). This may seem
1588 like an odd restriction to some, but doing this allows for simple code
1589 to be added at the begining or end of a method call without jeapordizing
1590 the normal functioning of the primary method or placing any extra
1591 responsibility on the code of the modifier. Of course if you have more
1592 complex needs, then use the I<around> modifier, which uses a variation
1593 of continutation passing style to allow for a high degree of flexibility.
1595 Before and around modifiers are called in last-defined-first-called order,
1596 while after modifiers are called in first-defined-first-called order. So
1597 the call tree might looks something like this:
1607 To see examples of using method modifiers, see the following examples
1608 included in the distribution; F<InstanceCountingClass>, F<Perl6Attribute>,
1609 F<AttributesWithHistory> and F<C3MethodDispatchOrder>. There is also a
1610 classic CLOS usage example in the test F<017_add_method_modifier.t>.
1612 =head3 What is the performance impact?
1614 Of course there is a performance cost associated with method modifiers,
1615 but we have made every effort to make that cost be directly proportional
1616 to the amount of modifier features you utilize.
1618 The wrapping method does it's best to B<only> do as much work as it
1619 absolutely needs to. In order to do this we have moved some of the
1620 performance costs to set-up time, where they are easier to amortize.
1622 All this said, my benchmarks have indicated the following:
1624 simple wrapper with no modifiers 100% slower
1625 simple wrapper with simple before modifier 400% slower
1626 simple wrapper with simple after modifier 450% slower
1627 simple wrapper with simple around modifier 500-550% slower
1628 simple wrapper with all 3 modifiers 1100% slower
1630 These numbers may seem daunting, but you must remember, every feature
1631 comes with some cost. To put things in perspective, just doing a simple
1632 C<AUTOLOAD> which does nothing but extract the name of the method called
1633 and return it costs about 400% over a normal method call.
1637 =item B<add_before_method_modifier ($method_name, $code)>
1639 This will wrap the method at C<$method_name> and the supplied C<$code>
1640 will be passed the C<@_> arguments, and called before the original
1641 method is called. As specified above, the return value of the I<before>
1642 method modifiers is ignored, and it's ability to modify C<@_> is
1643 fairly limited. If you need to do either of these things, use an
1644 C<around> method modifier.
1646 =item B<add_after_method_modifier ($method_name, $code)>
1648 This will wrap the method at C<$method_name> so that the original
1649 method will be called, it's return values stashed, and then the
1650 supplied C<$code> will be passed the C<@_> arguments, and called.
1651 As specified above, the return value of the I<after> method
1652 modifiers is ignored, and it cannot modify the return values of
1653 the original method. If you need to do either of these things, use an
1654 C<around> method modifier.
1656 =item B<add_around_method_modifier ($method_name, $code)>
1658 This will wrap the method at C<$method_name> so that C<$code>
1659 will be called and passed the original method as an extra argument
1660 at the begining of the C<@_> argument list. This is a variation of
1661 continuation passing style, where the function prepended to C<@_>
1662 can be considered a continuation. It is up to C<$code> if it calls
1663 the original method or not, there is no restriction on what the
1664 C<$code> can or cannot do.
1670 It should be noted that since there is no one consistent way to define
1671 the attributes of a class in Perl 5. These methods can only work with
1672 the information given, and can not easily discover information on
1673 their own. See L<Class::MOP::Attribute> for more details.
1677 =item B<attribute_metaclass>
1679 Returns the class name of the attribute metaclass, see L<Class::MOP::Attribute>
1680 for more information on the attribute metaclasses.
1682 =item B<get_attribute_map>
1684 This returns a HASH ref of name to attribute meta-object mapping.
1686 =item B<add_attribute ($attribute_meta_object | ($attribute_name, %attribute_spec))>
1688 This stores the C<$attribute_meta_object> (or creates one from the
1689 C<$attribute_name> and C<%attribute_spec>) in the B<Class::MOP::Class>
1690 instance associated with the given class. Unlike methods, attributes
1691 within the MOP are stored as meta-information only. They will be used
1692 later to construct instances from (see C<construct_instance> above).
1693 More details about the attribute meta-objects can be found in the
1694 L<Class::MOP::Attribute> or the L<Class::MOP/The Attribute protocol>
1697 It should be noted that any accessor, reader/writer or predicate
1698 methods which the C<$attribute_meta_object> has will be installed
1699 into the class at this time.
1702 If an attribute already exists for C<$attribute_name>, the old one
1703 will be removed (as well as removing all it's accessors), and then
1706 =item B<has_attribute ($attribute_name)>
1708 Checks to see if this class has an attribute by the name of
1709 C<$attribute_name> and returns a boolean.
1711 =item B<get_attribute ($attribute_name)>
1713 Returns the attribute meta-object associated with C<$attribute_name>,
1714 if none is found, it will return undef.
1716 =item B<remove_attribute ($attribute_name)>
1718 This will remove the attribute meta-object stored at
1719 C<$attribute_name>, then return the removed attribute meta-object.
1722 Removing an attribute will only affect future instances of
1723 the class, it will not make any attempt to remove the attribute from
1724 any existing instances of the class.
1726 It should be noted that any accessor, reader/writer or predicate
1727 methods which the attribute meta-object stored at C<$attribute_name>
1728 has will be removed from the class at this time. This B<will> make
1729 these attributes somewhat inaccessable in previously created
1730 instances. But if you are crazy enough to do this at runtime, then
1731 you are crazy enough to deal with something like this :).
1733 =item B<get_attribute_list>
1735 This returns a list of attribute names which are defined in the local
1736 class. If you want a list of all applicable attributes for a class,
1737 use the C<compute_all_applicable_attributes> method.
1739 =item B<compute_all_applicable_attributes>
1741 =item B<get_all_attributes>
1743 This will traverse the inheritance heirachy and return a list of all
1744 the applicable L<Class::MOP::Attribute> objects for this class.
1746 C<get_all_attributes> is an alias for consistency with C<get_all_methods>.
1748 =item B<find_attribute_by_name ($attr_name)>
1750 This method will traverse the inheritance heirachy and find the
1751 first attribute whose name matches C<$attr_name>, then return it.
1752 It will return undef if nothing is found.
1756 =head2 Class Immutability
1760 =item B<make_immutable (%options)>
1762 This method will invoke a tranforamtion upon the class which will
1763 make it immutable. Details of this transformation can be found in
1764 the L<Class::MOP::Immutable> documentation.
1766 =item B<make_mutable>
1768 This method will reverse tranforamtion upon the class which
1771 =item B<get_immutable_transformer>
1773 Return a transformer suitable for making this class immutable or, if this
1774 class is immutable, the transformer used to make it immutable.
1776 =item B<get_immutable_options>
1778 If the class is immutable, return the options used to make it immutable.
1780 =item B<create_immutable_transformer>
1782 Create a transformer suitable for making this class immutable
1788 Stevan Little E<lt>stevan@iinteractive.comE<gt>
1790 =head1 COPYRIGHT AND LICENSE
1792 Copyright 2006-2008 by Infinity Interactive, Inc.
1794 L<http://www.iinteractive.com>
1796 This library is free software; you can redistribute it and/or modify
1797 it under the same terms as Perl itself.