2 package Class::MOP::Class;
7 use Class::MOP::Instance;
8 use Class::MOP::Method::Wrapped;
9 use Class::MOP::Method::Accessor;
10 use Class::MOP::Method::Constructor;
11 use Class::MOP::Class::Immutable::Class::MOP::Class;
14 use Scalar::Util 'blessed', 'weaken';
15 use Sub::Name 'subname';
16 use Devel::GlobalDestruction 'in_global_destruction';
18 our $VERSION = '0.86';
19 $VERSION = eval $VERSION;
20 our $AUTHORITY = 'cpan:STEVAN';
22 use base 'Class::MOP::Module';
32 $package_name = shift;
35 $package_name = $options{package};
38 (defined $package_name && $package_name && !ref($package_name))
39 || confess "You must pass a package name and it cannot be blessed";
41 return Class::MOP::get_metaclass_by_name($package_name)
42 || $class->_construct_class_instance(package => $package_name, @_);
45 sub construct_class_instance {
46 Carp::cluck('The construct_class_instance method has been made private.'
47 . " The public version is deprecated and will be removed in a future release.\n");
48 shift->_construct_class_instance(@_);
51 # NOTE: (meta-circularity)
52 # this is a special form of _construct_instance
53 # (see below), which is used to construct class
54 # meta-object instances for any Class::MOP::*
55 # class. All other classes will use the more
56 # normal &construct_instance.
57 sub _construct_class_instance {
59 my $options = @_ == 1 ? $_[0] : {@_};
60 my $package_name = $options->{package};
61 (defined $package_name && $package_name)
62 || confess "You must pass a package name";
64 # return the metaclass if we have it cached,
65 # and it is still defined (it has not been
66 # reaped by DESTROY yet, which can happen
67 # annoyingly enough during global destruction)
69 if (defined(my $meta = Class::MOP::get_metaclass_by_name($package_name))) {
74 # we need to deal with the possibility
75 # of class immutability here, and then
76 # get the name of the class appropriately
78 ? ($class->is_immutable
79 ? $class->get_mutable_metaclass_name()
83 # now create the metaclass
85 if ($class eq 'Class::MOP::Class') {
86 $meta = $class->_new($options);
90 # it is safe to use meta here because
91 # class will always be a subclass of
92 # Class::MOP::Class, which defines meta
93 $meta = $class->meta->_construct_instance($options)
96 # and check the metaclass compatibility
97 $meta->_check_metaclass_compatibility();
99 Class::MOP::store_metaclass_by_name($package_name, $meta);
102 # we need to weaken any anon classes
103 # so that they can call DESTROY properly
104 Class::MOP::weaken_metaclass($package_name) if $meta->is_anon_class;
111 my $options = @_ == 1 ? $_[0] : {@_};
114 # inherited from Class::MOP::Package
115 'package' => $options->{package},
118 # since the following attributes will
119 # actually be loaded from the symbol
120 # table, and actually bypass the instance
121 # entirely, we can just leave these things
122 # listed here for reference, because they
123 # should not actually have a value associated
125 'namespace' => \undef,
127 # inherited from Class::MOP::Module
129 'authority' => \undef,
131 # defined in Class::MOP::Class
132 'superclasses' => \undef,
136 'attribute_metaclass' =>
137 ( $options->{'attribute_metaclass'} || 'Class::MOP::Attribute' ),
138 'method_metaclass' =>
139 ( $options->{'method_metaclass'} || 'Class::MOP::Method' ),
140 'wrapped_method_metaclass' => (
141 $options->{'wrapped_method_metaclass'}
142 || 'Class::MOP::Method::Wrapped'
144 'instance_metaclass' =>
145 ( $options->{'instance_metaclass'} || 'Class::MOP::Instance' ),
146 'immutable_trait' => (
147 $options->{'immutable_trait'}
148 || 'Class::MOP::Class::Immutable::Trait'
150 'constructor_name' => ( $options->{constructor_name} || 'new' ),
151 'constructor_class' => (
152 $options->{constructor_class} || 'Class::MOP::Method::Constructor'
154 'destructor_class' => $options->{destructor_class},
158 sub reset_package_cache_flag { (shift)->{'_package_cache_flag'} = undef }
159 sub update_package_cache_flag {
162 # we can manually update the cache number
163 # since we are actually adding the method
164 # to our cache as well. This avoids us
165 # having to regenerate the method_map.
167 $self->{'_package_cache_flag'} = Class::MOP::check_package_cache_flag($self->name);
171 sub check_metaclass_compatibility {
172 Carp::cluck('The check_metaclass_compatibility method has been made private.'
173 . " The public version is deprecated and will be removed in a future release.\n");
174 shift->_check_metaclass_compatibility(@_);
177 sub _check_metaclass_compatibility {
180 # this is always okay ...
181 return if ref($self) eq 'Class::MOP::Class' &&
182 $self->instance_metaclass eq 'Class::MOP::Instance';
184 my @class_list = $self->linearized_isa;
185 shift @class_list; # shift off $self->name
187 foreach my $superclass_name (@class_list) {
188 my $super_meta = Class::MOP::get_metaclass_by_name($superclass_name) || next;
191 # we need to deal with the possibility
192 # of class immutability here, and then
193 # get the name of the class appropriately
195 = $super_meta->is_immutable
196 ? $super_meta->get_mutable_metaclass_name()
199 ($self->isa($super_meta_type))
200 || confess "Class::MOP::class_of(" . $self->name . ") => ("
201 . (ref($self)) . ")" . " is not compatible with the " .
202 "Class::MOP::class_of(".$superclass_name . ") => ("
203 . ($super_meta_type) . ")";
205 # we also need to check that instance metaclasses
206 # are compatibile in the same the class.
207 ($self->instance_metaclass->isa($super_meta->instance_metaclass))
208 || confess "Class::MOP::class_of(" . $self->name . ")->instance_metaclass => (" . ($self->instance_metaclass) . ")" .
209 " is not compatible with the " .
210 "Class::MOP::class_of(" . $superclass_name . ")->instance_metaclass => (" . ($super_meta->instance_metaclass) . ")";
218 # this should be sufficient, if you have a
219 # use case where it is not, write a test and
221 my $ANON_CLASS_SERIAL = 0;
224 # we need a sufficiently annoying prefix
225 # this should suffice for now, this is
226 # used in a couple of places below, so
227 # need to put it up here for now.
228 my $ANON_CLASS_PREFIX = 'Class::MOP::Class::__ANON__::SERIAL::';
232 no warnings 'uninitialized';
233 $self->name =~ /^$ANON_CLASS_PREFIX/;
236 sub create_anon_class {
237 my ($class, %options) = @_;
238 my $package_name = $ANON_CLASS_PREFIX . ++$ANON_CLASS_SERIAL;
239 return $class->create($package_name, %options);
243 # this will only get called for
244 # anon-classes, all other calls
245 # are assumed to occur during
246 # global destruction and so don't
247 # really need to be handled explicitly
251 return if in_global_destruction(); # it'll happen soon anyway and this just makes things more complicated
253 no warnings 'uninitialized';
254 return unless $self->name =~ /^$ANON_CLASS_PREFIX/;
255 # Moose does a weird thing where it replaces the metaclass for
256 # class when fixing metaclass incompatibility. In that case,
257 # we don't want to clean out the namespace now. We can detect
258 # that because Moose will explicitly update the singleton
259 # cache in Class::MOP.
260 my $current_meta = Class::MOP::get_metaclass_by_name($self->name);
261 return if $current_meta ne $self;
263 my ($serial_id) = ($self->name =~ /^$ANON_CLASS_PREFIX(\d+)/);
265 foreach my $key (keys %{$ANON_CLASS_PREFIX . $serial_id}) {
266 delete ${$ANON_CLASS_PREFIX . $serial_id}{$key};
268 delete ${'main::' . $ANON_CLASS_PREFIX}{$serial_id . '::'};
273 # creating classes with MOP ...
276 my ( $class, @args ) = @_;
278 unshift @args, 'package' if @args % 2 == 1;
280 my (%options) = @args;
281 my $package_name = $options{package};
283 (ref $options{superclasses} eq 'ARRAY')
284 || confess "You must pass an ARRAY ref of superclasses"
285 if exists $options{superclasses};
287 (ref $options{attributes} eq 'ARRAY')
288 || confess "You must pass an ARRAY ref of attributes"
289 if exists $options{attributes};
291 (ref $options{methods} eq 'HASH')
292 || confess "You must pass a HASH ref of methods"
293 if exists $options{methods};
295 my (%initialize_options) = @args;
296 delete @initialize_options{qw(
304 my $meta = $class->initialize( $package_name => %initialize_options );
306 $meta->_instantiate_module( $options{version}, $options{authority} );
309 $meta->add_method('meta' => sub {
310 $class->initialize(ref($_[0]) || $_[0]);
313 $meta->superclasses(@{$options{superclasses}})
314 if exists $options{superclasses};
316 # process attributes first, so that they can
317 # install accessors, but locally defined methods
318 # can then overwrite them. It is maybe a little odd, but
319 # I think this should be the order of things.
320 if (exists $options{attributes}) {
321 foreach my $attr (@{$options{attributes}}) {
322 $meta->add_attribute($attr);
325 if (exists $options{methods}) {
326 foreach my $method_name (keys %{$options{methods}}) {
327 $meta->add_method($method_name, $options{methods}->{$method_name});
336 # all these attribute readers will be bootstrapped
337 # away in the Class::MOP bootstrap section
339 sub get_attribute_map { $_[0]->{'attributes'} }
340 sub attribute_metaclass { $_[0]->{'attribute_metaclass'} }
341 sub method_metaclass { $_[0]->{'method_metaclass'} }
342 sub wrapped_method_metaclass { $_[0]->{'wrapped_method_metaclass'} }
343 sub instance_metaclass { $_[0]->{'instance_metaclass'} }
344 sub immutable_trait { $_[0]->{'immutable_trait'} }
345 sub constructor_class { $_[0]->{'constructor_class'} }
346 sub constructor_name { $_[0]->{'constructor_name'} }
347 sub destructor_class { $_[0]->{'destructor_class'} }
349 # Instance Construction & Cloning
355 # we need to protect the integrity of the
356 # Class::MOP::Class singletons here, so we
357 # delegate this to &construct_class_instance
358 # which will deal with the singletons
359 return $class->_construct_class_instance(@_)
360 if $class->name->isa('Class::MOP::Class');
361 return $class->_construct_instance(@_);
364 sub construct_instance {
365 Carp::cluck('The construct_instance method has been made private.'
366 . " The public version is deprecated and will be removed in a future release.\n");
367 shift->_construct_instance(@_);
370 sub _construct_instance {
372 my $params = @_ == 1 ? $_[0] : {@_};
373 my $meta_instance = $class->get_meta_instance();
374 my $instance = $meta_instance->create_instance();
375 foreach my $attr ($class->get_all_attributes()) {
376 $attr->initialize_instance_slot($meta_instance, $instance, $params);
379 # this will only work for a HASH instance type
380 if ($class->is_anon_class) {
381 (Scalar::Util::reftype($instance) eq 'HASH')
382 || confess "Currently only HASH based instances are supported with instance of anon-classes";
384 # At some point we should make this official
385 # as a reserved slot name, but right now I am
386 # going to keep it here.
387 # my $RESERVED_MOP_SLOT = '__MOP__';
388 $instance->{'__MOP__'} = $class;
394 sub get_meta_instance {
396 $self->{'_meta_instance'} ||= $self->_create_meta_instance();
399 sub create_meta_instance {
400 Carp::cluck('The create_meta_instance method has been made private.'
401 . " The public version is deprecated and will be removed in a future release.\n");
402 shift->_create_meta_instance(@_);
405 sub _create_meta_instance {
408 my $instance = $self->instance_metaclass->new(
409 associated_metaclass => $self,
410 attributes => [ $self->get_all_attributes() ],
413 $self->add_meta_instance_dependencies()
414 if $instance->is_dependent_on_superclasses();
421 my $instance = shift;
422 (blessed($instance) && $instance->isa($class->name))
423 || confess "You must pass an instance of the metaclass (" . (ref $class ? $class->name : $class) . "), not ($instance)";
426 # we need to protect the integrity of the
427 # Class::MOP::Class singletons here, they
428 # should not be cloned.
429 return $instance if $instance->isa('Class::MOP::Class');
430 $class->_clone_instance($instance, @_);
434 Carp::cluck('The clone_instance method has been made private.'
435 . " The public version is deprecated and will be removed in a future release.\n");
436 shift->_clone_instance(@_);
439 sub _clone_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->get_all_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) = @_;
458 my $old_metaclass = Class::MOP::class_of($instance);
460 my $old_class = $old_metaclass ? $old_metaclass->name : blessed($instance);
461 $self->name->isa($old_class)
462 || confess "You may rebless only into a subclass of ($old_class), of which (". $self->name .") isn't.";
464 $old_metaclass->rebless_instance_away($instance, $self, %params)
467 my $meta_instance = $self->get_meta_instance();
470 # we use $_[1] here because of t/306_rebless_overload.t regressions on 5.8.8
471 $meta_instance->rebless_instance_structure($_[1], $self);
473 foreach my $attr ( $self->get_all_attributes ) {
474 if ( $attr->has_value($instance) ) {
475 if ( defined( my $init_arg = $attr->init_arg ) ) {
476 $params{$init_arg} = $attr->get_value($instance)
477 unless exists $params{$init_arg};
480 $attr->set_value($instance, $attr->get_value($instance));
485 foreach my $attr ($self->get_all_attributes) {
486 $attr->initialize_instance_slot($meta_instance, $instance, \%params);
492 sub rebless_instance_away {
493 # this intentionally does nothing, it is just a hook
500 my $var_spec = { sigil => '@', type => 'ARRAY', name => 'ISA' };
503 @{$self->get_package_symbol($var_spec)} = @supers;
506 # on 5.8 and below, we need to call
507 # a method to get Perl to detect
508 # a cycle in the class hierarchy
509 my $class = $self->name;
513 # we need to check the metaclass
514 # compatibility here so that we can
515 # be sure that the superclass is
516 # not potentially creating an issues
517 # we don't know about
519 $self->_check_metaclass_compatibility();
520 $self->_superclasses_updated();
522 @{$self->get_package_symbol($var_spec)};
525 sub _superclasses_updated {
527 $self->update_meta_instance_dependencies();
532 my $super_class = $self->name;
534 return @{ $super_class->mro::get_isarev() };
537 sub direct_subclasses {
539 my $super_class = $self->name;
544 } Class::MOP::Class->initialize($_)->superclasses
549 return @{ mro::get_linear_isa( (shift)->name ) };
552 sub class_precedence_list {
554 my $name = $self->name;
556 unless (Class::MOP::IS_RUNNING_ON_5_10()) {
558 # We need to check for circular inheritance here
559 # if we are are not on 5.10, cause 5.8 detects it
560 # late. This will do nothing if all is well, and
561 # blow up otherwise. Yes, it's an ugly hack, better
562 # suggestions are welcome.
564 ($name || return)->isa('This is a test for circular inheritance')
567 # if our mro is c3, we can
568 # just grab the linear_isa
569 if (mro::get_mro($name) eq 'c3') {
570 return @{ mro::get_linear_isa($name) }
574 # we can't grab the linear_isa for dfs
575 # since it has all the duplicates
580 $self->initialize($_)->class_precedence_list()
581 } $self->superclasses()
588 sub wrap_method_body {
589 my ( $self, %args ) = @_;
591 ('CODE' eq ref $args{body})
592 || confess "Your code block must be a CODE reference";
594 $self->method_metaclass->wrap(
595 package_name => $self->name,
601 my ($self, $method_name, $method) = @_;
602 (defined $method_name && $method_name)
603 || confess "You must define a method name";
606 if (blessed($method)) {
607 $body = $method->body;
608 if ($method->package_name ne $self->name) {
609 $method = $method->clone(
610 package_name => $self->name,
612 ) if $method->can('clone');
617 $method = $self->wrap_method_body( body => $body, name => $method_name );
620 $method->attach_to_class($self);
622 $self->get_method_map->{$method_name} = $method;
624 my ( $current_package, $current_name ) = Class::MOP::get_code_info($body);
626 if ( $current_name eq '__ANON__' ) {
627 my $full_method_name = ($self->name . '::' . $method_name);
628 subname($full_method_name => $body);
631 $self->add_package_symbol(
632 { sigil => '&', type => 'CODE', name => $method_name },
638 my $fetch_and_prepare_method = sub {
639 my ($self, $method_name) = @_;
640 my $wrapped_metaclass = $self->wrapped_method_metaclass;
642 my $method = $self->get_method($method_name);
643 # if we dont have local ...
645 # try to find the next method
646 $method = $self->find_next_method_by_name($method_name);
647 # die if it does not exist
649 || confess "The method '$method_name' was not found in the inheritance hierarchy for " . $self->name;
650 # and now make sure to wrap it
651 # even if it is already wrapped
652 # because we need a new sub ref
653 $method = $wrapped_metaclass->wrap($method);
656 # now make sure we wrap it properly
657 $method = $wrapped_metaclass->wrap($method)
658 unless $method->isa($wrapped_metaclass);
660 $self->add_method($method_name => $method);
664 sub add_before_method_modifier {
665 my ($self, $method_name, $method_modifier) = @_;
666 (defined $method_name && $method_name)
667 || confess "You must pass in a method name";
668 my $method = $fetch_and_prepare_method->($self, $method_name);
669 $method->add_before_modifier(
670 subname(':before' => $method_modifier)
674 sub add_after_method_modifier {
675 my ($self, $method_name, $method_modifier) = @_;
676 (defined $method_name && $method_name)
677 || confess "You must pass in a method name";
678 my $method = $fetch_and_prepare_method->($self, $method_name);
679 $method->add_after_modifier(
680 subname(':after' => $method_modifier)
684 sub add_around_method_modifier {
685 my ($self, $method_name, $method_modifier) = @_;
686 (defined $method_name && $method_name)
687 || confess "You must pass in a method name";
688 my $method = $fetch_and_prepare_method->($self, $method_name);
689 $method->add_around_modifier(
690 subname(':around' => $method_modifier)
695 # the methods above used to be named like this:
696 # ${pkg}::${method}:(before|after|around)
697 # but this proved problematic when using one modifier
698 # to wrap multiple methods (something which is likely
699 # to happen pretty regularly IMO). So instead of naming
700 # it like this, I have chosen to just name them purely
701 # with their modifier names, like so:
702 # :(before|after|around)
703 # The fact is that in a stack trace, it will be fairly
704 # evident from the context what method they are attached
705 # to, and so don't need the fully qualified name.
709 Carp::cluck("The alias_method method is deprecated. Use add_method instead.\n");
711 shift->add_method(@_);
715 my ($self, $method_name) = @_;
716 (defined $method_name && $method_name)
717 || confess "You must define a method name";
719 exists $self->get_method_map->{$method_name};
723 my ($self, $method_name) = @_;
724 (defined $method_name && $method_name)
725 || confess "You must define a method name";
727 return $self->get_method_map->{$method_name};
731 my ($self, $method_name) = @_;
732 (defined $method_name && $method_name)
733 || confess "You must define a method name";
735 my $removed_method = delete $self->get_method_map->{$method_name};
737 $self->remove_package_symbol(
738 { sigil => '&', type => 'CODE', name => $method_name }
741 $removed_method->detach_from_class if $removed_method;
743 $self->update_package_cache_flag; # still valid, since we just removed the method from the map
745 return $removed_method;
748 sub get_method_list {
750 keys %{$self->get_method_map};
753 sub find_method_by_name {
754 my ($self, $method_name) = @_;
755 (defined $method_name && $method_name)
756 || confess "You must define a method name to find";
757 foreach my $class ($self->linearized_isa) {
758 # fetch the meta-class ...
759 my $meta = $self->initialize($class);
760 return $meta->get_method($method_name)
761 if $meta->has_method($method_name);
766 sub get_all_methods {
768 my %methods = map { %{ $self->initialize($_)->get_method_map } } reverse $self->linearized_isa;
769 return values %methods;
772 sub compute_all_applicable_methods {
773 Carp::cluck('The compute_all_applicable_methods method is deprecated.'
774 . " Use get_all_methods instead.\n");
779 class => $_->package_name,
780 code => $_, # sigh, overloading
782 } shift->get_all_methods(@_);
785 sub get_all_method_names {
788 grep { $uniq{$_}++ == 0 } map { $_->name } $self->get_all_methods;
791 sub find_all_methods_by_name {
792 my ($self, $method_name) = @_;
793 (defined $method_name && $method_name)
794 || confess "You must define a method name to find";
796 foreach my $class ($self->linearized_isa) {
797 # fetch the meta-class ...
798 my $meta = $self->initialize($class);
800 name => $method_name,
802 code => $meta->get_method($method_name)
803 } if $meta->has_method($method_name);
808 sub find_next_method_by_name {
809 my ($self, $method_name) = @_;
810 (defined $method_name && $method_name)
811 || confess "You must define a method name to find";
812 my @cpl = $self->linearized_isa;
813 shift @cpl; # discard ourselves
814 foreach my $class (@cpl) {
815 # fetch the meta-class ...
816 my $meta = $self->initialize($class);
817 return $meta->get_method($method_name)
818 if $meta->has_method($method_name);
827 # either we have an attribute object already
828 # or we need to create one from the args provided
829 my $attribute = blessed($_[0]) ? $_[0] : $self->attribute_metaclass->new(@_);
830 # make sure it is derived from the correct type though
831 ($attribute->isa('Class::MOP::Attribute'))
832 || confess "Your attribute must be an instance of Class::MOP::Attribute (or a subclass)";
834 # first we attach our new attribute
835 # because it might need certain information
836 # about the class which it is attached to
837 $attribute->attach_to_class($self);
839 # then we remove attributes of a conflicting
840 # name here so that we can properly detach
841 # the old attr object, and remove any
842 # accessors it would have generated
843 if ( $self->has_attribute($attribute->name) ) {
844 $self->remove_attribute($attribute->name);
846 $self->invalidate_meta_instances();
849 # get our count of previously inserted attributes and
850 # increment by one so this attribute knows its order
851 my $order = (scalar keys %{$self->get_attribute_map}) - 1;
852 $attribute->_set_insertion_order($order + 1);
854 # then onto installing the new accessors
855 $self->get_attribute_map->{$attribute->name} = $attribute;
857 # invalidate package flag here
861 eval { $attribute->install_accessors() };
865 $self->remove_attribute($attribute->name);
872 sub update_meta_instance_dependencies {
875 if ( $self->{meta_instance_dependencies} ) {
876 return $self->add_meta_instance_dependencies;
880 sub add_meta_instance_dependencies {
883 $self->remove_meta_instance_dependencies;
885 my @attrs = $self->get_all_attributes();
888 my @classes = grep { not $seen{$_->name}++ } map { $_->associated_class } @attrs;
890 foreach my $class ( @classes ) {
891 $class->add_dependent_meta_instance($self);
894 $self->{meta_instance_dependencies} = \@classes;
897 sub remove_meta_instance_dependencies {
900 if ( my $classes = delete $self->{meta_instance_dependencies} ) {
901 foreach my $class ( @$classes ) {
902 $class->remove_dependent_meta_instance($self);
912 sub add_dependent_meta_instance {
913 my ( $self, $metaclass ) = @_;
914 push @{ $self->{dependent_meta_instances} }, $metaclass;
917 sub remove_dependent_meta_instance {
918 my ( $self, $metaclass ) = @_;
919 my $name = $metaclass->name;
920 @$_ = grep { $_->name ne $name } @$_ for $self->{dependent_meta_instances};
923 sub invalidate_meta_instances {
925 $_->invalidate_meta_instance() for $self, @{ $self->{dependent_meta_instances} };
928 sub invalidate_meta_instance {
930 undef $self->{_meta_instance};
934 my ($self, $attribute_name) = @_;
935 (defined $attribute_name && $attribute_name)
936 || confess "You must define an attribute name";
937 exists $self->get_attribute_map->{$attribute_name};
941 my ($self, $attribute_name) = @_;
942 (defined $attribute_name && $attribute_name)
943 || confess "You must define an attribute name";
944 return $self->get_attribute_map->{$attribute_name}
946 # this will return undef anyway, so no need ...
947 # if $self->has_attribute($attribute_name);
951 sub remove_attribute {
952 my ($self, $attribute_name) = @_;
953 (defined $attribute_name && $attribute_name)
954 || confess "You must define an attribute name";
955 my $removed_attribute = $self->get_attribute_map->{$attribute_name};
956 return unless defined $removed_attribute;
957 delete $self->get_attribute_map->{$attribute_name};
958 $self->invalidate_meta_instances();
959 $removed_attribute->remove_accessors();
960 $removed_attribute->detach_from_class();
961 return $removed_attribute;
964 sub get_attribute_list {
966 keys %{$self->get_attribute_map};
969 sub get_all_attributes {
971 my %attrs = map { %{ $self->initialize($_)->get_attribute_map } } reverse $self->linearized_isa;
972 return values %attrs;
975 sub compute_all_applicable_attributes {
976 Carp::cluck('The compute_all_applicable_attributes method has been deprecated.'
977 . " Use get_all_attributes instead.\n");
979 shift->get_all_attributes(@_);
982 sub find_attribute_by_name {
983 my ($self, $attr_name) = @_;
984 foreach my $class ($self->linearized_isa) {
985 # fetch the meta-class ...
986 my $meta = $self->initialize($class);
987 return $meta->get_attribute($attr_name)
988 if $meta->has_attribute($attr_name);
993 # check if we can reinitialize
997 # if any local attr is defined
998 return if $self->get_attribute_list;
1000 # or any non-declared methods
1001 if ( my @methods = values %{ $self->get_method_map } ) {
1002 my $metaclass = $self->method_metaclass;
1003 foreach my $method ( @methods ) {
1004 return if $method->isa("Class::MOP::Method::Generated");
1005 # FIXME do we need to enforce this too? return unless $method->isa($metaclass);
1014 sub is_mutable { 1 }
1015 sub is_immutable { 0 }
1017 sub _immutable_options {
1018 my ( $self, @args ) = @_;
1021 inline_accessors => 1,
1022 inline_constructor => 1,
1023 inline_destructor => 0,
1025 immutable_trait => $self->immutable_trait,
1026 constructor_name => $self->constructor_name,
1027 constructor_class => $self->constructor_class,
1028 destructor_class => $self->destructor_class,
1033 sub make_immutable {
1034 my ( $self, @args ) = @_;
1036 if ( $self->is_mutable ) {
1037 $self->_initialize_immutable( $self->_immutable_options(@args) );
1038 $self->_rebless_as_immutable(@args);
1049 if ( $self->is_immutable ) {
1050 my @args = $self->immutable_options;
1051 $self->_rebless_as_mutable();
1052 $self->_remove_inlined_code(@args);
1053 delete $self->{__immutable};
1061 sub _rebless_as_immutable {
1062 my ( $self, @args ) = @_;
1064 $self->{__immutable}{original_class} = ref $self;
1066 bless $self => $self->_immutable_metaclass(@args);
1069 sub _immutable_metaclass {
1070 my ( $self, %args ) = @_;
1072 if ( my $class = $args{immutable_metaclass} ) {
1076 my $trait = $args{immutable_trait} = $self->immutable_trait
1077 || confess "no immutable trait specified for $self";
1079 my $meta_attr = $self->meta->find_attribute_by_name("immutable_trait");
1083 if ( $meta_attr and $trait eq $meta_attr->default ) {
1084 # if the trait is the same as the default we try and pick a
1085 # predictable name for the immutable metaclass
1086 $class_name = 'Class::MOP::Class::Immutable::' . ref($self);
1089 $class_name = join '::', 'Class::MOP::Class::Immutable::CustomTrait',
1090 $trait, 'ForMetaClass', ref($self);
1093 if ( Class::MOP::is_class_loaded($class_name) ) {
1094 if ( $class_name->isa($trait) ) {
1099 "$class_name is already defined but does not inherit $trait";
1103 my @super = ( $trait, ref($self) );
1105 my $meta = Class::MOP::Class->initialize($class_name);
1106 $meta->superclasses(@super);
1108 $meta->make_immutable;
1114 sub _remove_inlined_code {
1117 $self->remove_method( $_->name ) for $self->_inlined_methods;
1119 delete $self->{__immutable}{inlined_methods};
1122 sub _inlined_methods { @{ $_[0]{__immutable}{inlined_methods} || [] } }
1124 sub _add_inlined_method {
1125 my ( $self, $method ) = @_;
1127 push @{ $self->{__immutable}{inlined_methods} ||= [] }, $method;
1130 sub _initialize_immutable {
1131 my ( $self, %args ) = @_;
1133 $self->{__immutable}{options} = \%args;
1134 $self->_install_inlined_code(%args);
1137 sub _install_inlined_code {
1138 my ( $self, %args ) = @_;
1141 $self->_inline_accessors(%args) if $args{inline_accessors};
1142 $self->_inline_constructor(%args) if $args{inline_constructor};
1143 $self->_inline_destructor(%args) if $args{inline_destructor};
1146 sub _rebless_as_mutable {
1149 bless $self, $self->get_mutable_metaclass_name;
1154 sub _inline_accessors {
1157 foreach my $attr_name ( $self->get_attribute_list ) {
1158 $self->get_attribute($attr_name)->install_accessors(1);
1162 sub _inline_constructor {
1163 my ( $self, %args ) = @_;
1165 my $name = $args{constructor_name};
1167 if ( $self->has_method($name) && !$args{replace_constructor} ) {
1168 my $class = $self->name;
1169 warn "Not inlining a constructor for $class since it defines"
1170 . " its own constructor.\n"
1171 . "If you are certain you don't need to inline your"
1172 . " constructor, specify inline_constructor => 0 in your"
1173 . " call to $class->meta->make_immutable\n";
1177 my $constructor_class = $args{constructor_class};
1179 Class::MOP::load_class($constructor_class);
1181 my $constructor = $constructor_class->new(
1185 package_name => $self->name,
1189 if ( $args{replace_constructor} or $constructor->can_be_inlined ) {
1190 $self->add_method( $name => $constructor );
1191 $self->_add_inlined_method($constructor);
1195 sub _inline_destructor {
1196 my ( $self, %args ) = @_;
1198 ( exists $args{destructor_class} && defined $args{destructor_class} )
1199 || confess "The 'inline_destructor' option is present, but "
1200 . "no destructor class was specified";
1202 if ( $self->has_method('DESTROY') && ! $args{replace_destructor} ) {
1203 my $class = $self->name;
1204 warn "Not inlining a destructor for $class since it defines"
1205 . " its own destructor.\n";
1209 my $destructor_class = $args{destructor_class};
1211 Class::MOP::load_class($destructor_class);
1213 return unless $destructor_class->is_needed($self);
1215 my $destructor = $destructor_class->new(
1218 package_name => $self->name,
1222 if ( $args{replace_destructor} or $destructor->can_be_inlined ) {
1223 $self->add_method( 'DESTROY' => $destructor );
1224 $self->_add_inlined_method($destructor);
1236 Class::MOP::Class - Class Meta Object
1240 # assuming that class Foo
1241 # has been defined, you can
1243 # use this for introspection ...
1245 # add a method to Foo ...
1246 Foo->meta->add_method( 'bar' => sub {...} )
1248 # get a list of all the classes searched
1249 # the method dispatcher in the correct order
1250 Foo->meta->class_precedence_list()
1252 # remove a method from Foo
1253 Foo->meta->remove_method('bar');
1255 # or use this to actually create classes ...
1257 Class::MOP::Class->create(
1260 superclasses => ['Foo'],
1262 Class::MOP::Attribute->new('$bar'),
1263 Class::MOP::Attribute->new('$baz'),
1266 calculate_bar => sub {...},
1267 construct_baz => sub {...}
1274 The Class Protocol is the largest and most complex part of the
1275 Class::MOP meta-object protocol. It controls the introspection and
1276 manipulation of Perl 5 classes, and it can create them as well. The
1277 best way to understand what this module can do, is to read the
1278 documentation for each of its methods.
1282 C<Class::MOP::Class> is a subclass of L<Class::MOP::Module>.
1286 =head2 Class construction
1288 These methods all create new C<Class::MOP::Class> objects. These
1289 objects can represent existing classes, or they can be used to create
1290 new classes from scratch.
1292 The metaclass object for a given class is a singleton. If you attempt
1293 to create a metaclass for the same class twice, you will just get the
1298 =item B<< Class::MOP::Class->create($package_name, %options) >>
1300 This method creates a new C<Class::MOP::Class> object with the given
1301 package name. It accepts a number of options.
1307 An optional version number for the newly created package.
1311 An optional authority for the newly created package.
1313 =item * superclasses
1315 An optional array reference of superclass names.
1319 An optional hash reference of methods for the class. The keys of the
1320 hash reference are method names, and values are subroutine references.
1324 An optional array reference of attributes.
1326 An attribute can be passed as an existing L<Class::MOP::Attribute>
1327 object, I<or> or as a hash reference of options which will be passed
1328 to the attribute metaclass's constructor.
1332 =item B<< Class::MOP::Class->create_anon_class(%options) >>
1334 This method works just like C<< Class::MOP::Class->create >> but it
1335 creates an "anonymous" class. In fact, the class does have a name, but
1336 that name is a unique name generated internally by this module.
1338 It accepts the same C<superclasses>, C<methods>, and C<attributes>
1339 parameters that C<create> accepts.
1341 Anonymous classes are destroyed once the metaclass they are attached
1342 to goes out of scope, and will be removed from Perl's internal symbol
1345 All instances of an anonymous class keep a special reference to the
1346 metaclass object, which prevents the metaclass from going out of scope
1347 while any instances exist.
1349 This only works if the instance if based on a hash reference, however.
1351 =item B<< Class::MOP::Class->initialize($package_name, %options) >>
1353 This method will initialize a C<Class::MOP::Class> object for the
1354 named package. Unlike C<create>, this method I<will not> create a new
1357 The purpose of this method is to retrieve a C<Class::MOP::Class>
1358 object for introspecting an existing class.
1360 If an existing C<Class::MOP::Class> object exists for the named
1361 package, it will be returned, and any options provided will be
1364 If the object does not yet exist, it will be created.
1366 The valid options that can be passed to this method are
1367 C<attribute_metaclass>, C<method_metaclass>,
1368 C<wrapped_method_metaclass>, and C<instance_metaclass>. These are all
1369 optional, and default to the appropriate class in the C<Class::MOP>
1374 =head2 Object instance construction and cloning
1376 These methods are all related to creating and/or cloning object
1381 =item B<< $metaclass->clone_object($instance, %params) >>
1383 This method clones an existing object instance. Any parameters you
1384 provide are will override existing attribute values in the object.
1386 This is a convenience method for cloning an object instance, then
1387 blessing it into the appropriate package.
1389 You could implement a clone method in your class, using this method:
1392 my ($self, %params) = @_;
1393 $self->meta->clone_object($self, %params);
1396 =item B<< $metaclass->rebless_instance($instance, %params) >>
1398 This method changes the class of C<$instance> to the metaclass's class.
1400 You can only rebless an instance into a subclass of its current
1401 class. If you pass any additional parameters, these will be treated
1402 like constructor parameters and used to initialize the object's
1403 attributes. Any existing attributes that are already set will be
1406 Before reblessing the instance, this method will call
1407 C<rebless_instance_away> on the instance's current metaclass. This method
1408 will be passed the instance, the new metaclass, and any parameters
1409 specified to C<rebless_instance>. By default, C<rebless_instance_away>
1410 does nothing; it is merely a hook.
1412 =item B<< $metaclass->new_object(%params) >>
1414 This method is used to create a new object of the metaclass's
1415 class. Any parameters you provide are used to initialize the
1416 instance's attributes.
1418 =item B<< $metaclass->instance_metaclass >>
1420 Returns the class name of the instance metaclass, see
1421 L<Class::MOP::Instance> for more information on the instance
1424 =item B<< $metaclass->get_meta_instance >>
1426 Returns an instance of the C<instance_metaclass> to be used in the
1427 construction of a new instance of the class.
1431 =head2 Informational predicates
1433 These are a few predicate methods for asking information about the
1438 =item B<< $metaclass->is_anon_class >>
1440 This returns true if the class was created by calling C<<
1441 Class::MOP::Class->create_anon_class >>.
1443 =item B<< $metaclass->is_mutable >>
1445 This returns true if the class is still mutable.
1447 =item B<< $metaclass->is_immutable >>
1449 This returns true if the class has been made immutable.
1451 =item B<< $metaclass->is_pristine >>
1453 A class is I<not> pristine if it has non-inherited attributes or if it
1454 has any generated methods.
1458 =head2 Inheritance Relationships
1462 =item B<< $metaclass->superclasses(@superclasses) >>
1464 This is a read-write accessor which represents the superclass
1465 relationships of the metaclass's class.
1467 This is basically sugar around getting and setting C<@ISA>.
1469 =item B<< $metaclass->class_precedence_list >>
1471 This returns a list of all of the class's ancestor classes. The
1472 classes are returned in method dispatch order.
1474 =item B<< $metaclass->linearized_isa >>
1476 This returns a list based on C<class_precedence_list> but with all
1479 =item B<< $metaclass->subclasses >>
1481 This returns a list of all subclasses for this class, even indirect
1484 =item B<< $metaclass->direct_subclasses >>
1486 This returns a list of immediate subclasses for this class, which does not
1487 include indirect subclasses.
1491 =head2 Method introspection and creation
1493 These methods allow you to introspect a class's methods, as well as
1494 add, remove, or change methods.
1496 Determining what is truly a method in a Perl 5 class requires some
1497 heuristics (aka guessing).
1499 Methods defined outside the package with a fully qualified name (C<sub
1500 Package::name { ... }>) will be included. Similarly, methods named
1501 with a fully qualified name using L<Sub::Name> are also included.
1503 However, we attempt to ignore imported functions.
1505 Ultimately, we are using heuristics to determine what truly is a
1506 method in a class, and these heuristics may get the wrong answer in
1507 some edge cases. However, for most "normal" cases the heuristics work
1512 =item B<< $metaclass->get_method($method_name) >>
1514 This will return a L<Class::MOP::Method> for the specified
1515 C<$method_name>. If the class does not have the specified method, it
1518 =item B<< $metaclass->has_method($method_name) >>
1520 Returns a boolean indicating whether or not the class defines the
1521 named method. It does not include methods inherited from parent
1524 =item B<< $metaclass->get_method_map >>
1526 Returns a hash reference representing the methods defined in this
1527 class. The keys are method names and the values are
1528 L<Class::MOP::Method> objects.
1530 =item B<< $metaclass->get_method_list >>
1532 This will return a list of method I<names> for all methods defined in
1535 =item B<< $metaclass->get_all_methods >>
1537 This will traverse the inheritance hierarchy and return a list of all
1538 the L<Class::MOP::Method> objects for this class and its parents.
1540 =item B<< $metaclass->find_method_by_name($method_name) >>
1542 This will return a L<Class::MOP::Method> for the specified
1543 C<$method_name>. If the class does not have the specified method, it
1546 Unlike C<get_method>, this method I<will> look for the named method in
1549 =item B<< $metaclass->get_all_method_names >>
1551 This will return a list of method I<names> for all of this class's
1552 methods, including inherited methods.
1554 =item B<< $metaclass->find_all_methods_by_name($method_name) >>
1556 This method looks for the named method in the class and all of its
1557 parents. It returns every matching method it finds in the inheritance
1558 tree, so it returns a list of methods.
1560 Each method is returned as a hash reference with three keys. The keys
1561 are C<name>, C<class>, and C<code>. The C<code> key has a
1562 L<Class::MOP::Method> object as its value.
1564 The list of methods is distinct.
1566 =item B<< $metaclass->find_next_method_by_name($method_name) >>
1568 This method returns the first method in any superclass matching the
1569 given name. It is effectively the method that C<SUPER::$method_name>
1572 =item B<< $metaclass->add_method($method_name, $method) >>
1574 This method takes a method name and a subroutine reference, and adds
1575 the method to the class.
1577 The subroutine reference can be a L<Class::MOP::Method>, and you are
1578 strongly encouraged to pass a meta method object instead of a code
1579 reference. If you do so, that object gets stored as part of the
1580 class's method map directly. If not, the meta information will have to
1581 be recreated later, and may be incorrect.
1583 If you provide a method object, this method will clone that object if
1584 the object's package name does not match the class name. This lets us
1585 track the original source of any methods added from other classes
1586 (notably Moose roles).
1588 =item B<< $metaclass->remove_method($method_name) >>
1590 Remove the named method from the class. This method returns the
1591 L<Class::MOP::Method> object for the method.
1593 =item B<< $metaclass->method_metaclass >>
1595 Returns the class name of the method metaclass, see
1596 L<Class::MOP::Method> for more information on the method metaclass.
1598 =item B<< $metaclass->wrapped_method_metaclass >>
1600 Returns the class name of the wrapped method metaclass, see
1601 L<Class::MOP::Method::Wrapped> for more information on the wrapped
1606 =head2 Attribute introspection and creation
1608 Because Perl 5 does not have a core concept of attributes in classes,
1609 we can only return information about attributes which have been added
1610 via this class's methods. We cannot discover information about
1611 attributes which are defined in terms of "regular" Perl 5 methods.
1615 =item B<< $metaclass->get_attribute($attribute_name) >>
1617 This will return a L<Class::MOP::Attribute> for the specified
1618 C<$attribute_name>. If the class does not have the specified
1619 attribute, it returns C<undef>.
1621 NOTE that get_attribute does not search superclasses, for that you
1622 need to use C<find_attribute_by_name>.
1624 =item B<< $metaclass->has_attribute($attribute_name) >>
1626 Returns a boolean indicating whether or not the class defines the
1627 named attribute. It does not include attributes inherited from parent
1630 =item B<< $metaclass->get_attribute_map >>
1632 Returns a hash reference representing the attributes defined in this
1633 class. The keys are attribute names and the values are
1634 L<Class::MOP::Attribute> objects.
1636 =item B<< $metaclass->get_attribute_list >>
1638 This will return a list of attributes I<names> for all attributes
1639 defined in this class.
1641 =item B<< $metaclass->get_all_attributes >>
1643 This will traverse the inheritance hierarchy and return a list of all
1644 the L<Class::MOP::Attribute> objects for this class and its parents.
1646 =item B<< $metaclass->find_attribute_by_name($attribute_name) >>
1648 This will return a L<Class::MOP::Attribute> for the specified
1649 C<$attribute_name>. If the class does not have the specified
1650 attribute, it returns C<undef>
1652 Unlike C<get_attribute>, this attribute I<will> look for the named
1653 attribute in superclasses.
1655 =item B<< $metaclass->add_attribute(...) >>
1657 This method accepts either an existing L<Class::MOP::Attribute>
1658 object, or parameters suitable for passing to that class's C<new>
1661 The attribute provided will be added to the class.
1663 Any accessor methods defined by the attribute will be added to the
1664 class when the attribute is added.
1666 If an attribute of the same name already exists, the old attribute
1667 will be removed first.
1669 =item B<< $metaclass->remove_attribute($attribute_name) >>
1671 This will remove the named attribute from the class, and
1672 L<Class::MOP::Attribute> object.
1674 Removing an attribute also removes any accessor methods defined by the
1677 However, note that removing an attribute will only affect I<future>
1678 object instances created for this class, not existing instances.
1680 =item B<< $metaclass->attribute_metaclass >>
1682 Returns the class name of the attribute metaclass for this class. By
1683 default, this is L<Class::MOP::Attribute>. for more information on
1687 =head2 Class Immutability
1689 Making a class immutable "freezes" the class definition. You can no
1690 longer call methods which alter the class, such as adding or removing
1691 methods or attributes.
1693 Making a class immutable lets us optimize the class by inlining some
1694 methods, and also allows us to optimize some methods on the metaclass
1697 After immutabilization, the metaclass object will cache most
1698 informational methods such as C<get_method_map> and
1699 C<get_all_attributes>. Methods which would alter the class, such as
1700 C<add_attribute>, C<add_method>, and so on will throw an error on an
1701 immutable metaclass object.
1703 The immutabilization system in L<Moose> takes much greater advantage
1704 of the inlining features than Class::MOP itself does.
1708 =item B<< $metaclass->make_immutable(%options) >>
1710 This method will create an immutable transformer and uses it to make
1711 the class and its metaclass object immutable.
1713 This method accepts the following options:
1717 =item * inline_accessors
1719 =item * inline_constructor
1721 =item * inline_destructor
1723 These are all booleans indicating whether the specified method(s)
1726 By default, accessors and the constructor are inlined, but not the
1729 =item * immutable_trait
1731 The name of a class which will be used as a parent class for the
1732 metaclass object being made immutable. This "trait" implements the
1733 post-immutability functionlity of the metaclass (but not the
1734 transformation itself).
1736 This defaults to L<Class::MOP::Class::Immutable::Trait>.
1738 =item * constructor_name
1740 This is the constructor method name. This defaults to "new".
1742 =item * constructor_class
1744 The name of the method metaclass for constructors. It will be used to
1745 generate the inlined constructor. This defaults to
1746 "Class::MOP::Method::Constructor".
1748 =item * replace_constructor
1750 This is a boolean indicating whether an existing constructor should be
1751 replaced when inlining a constructor. This defaults to false.
1753 =item * destructor_class
1755 The name of the method metaclass for destructors. It will be used to
1756 generate the inlined destructor. This defaults to
1757 "Class::MOP::Method::Denstructor".
1759 =item * replace_destructor
1761 This is a boolean indicating whether an existing destructor should be
1762 replaced when inlining a destructor. This defaults to false.
1766 =item B<< $metaclass->make_mutable >>
1768 Calling this method reverse the immutabilization transformation.
1772 =head2 Method Modifiers
1774 Method modifiers are hooks which allow a method to be wrapped with
1775 I<before>, I<after> and I<around> method modifiers. Every time a
1776 method is called, it's modifiers are also called.
1778 A class can modify its own methods, as well as methods defined in
1781 =head3 How method modifiers work?
1783 Method modifiers work by wrapping the original method and then
1784 replacing it in the class's symbol table. The wrappers will handle
1785 calling all the modifiers in the appropriate order and preserving the
1786 calling context for the original method.
1788 The return values of C<before> and C<after> modifiers are
1789 ignored. This is because their purpose is B<not> to filter the input
1790 and output of the primary method (this is done with an I<around>
1793 This may seem like an odd restriction to some, but doing this allows
1794 for simple code to be added at the beginning or end of a method call
1795 without altering the function of the wrapped method or placing any
1796 extra responsibility on the code of the modifier.
1798 Of course if you have more complex needs, you can use the C<around>
1799 modifier which allows you to change both the parameters passed to the
1800 wrapped method, as well as its return value.
1802 Before and around modifiers are called in last-defined-first-called
1803 order, while after modifiers are called in first-defined-first-called
1804 order. So the call tree might looks something like this:
1816 =head3 What is the performance impact?
1818 Of course there is a performance cost associated with method
1819 modifiers, but we have made every effort to make that cost directly
1820 proportional to the number of modifier features you utilize.
1822 The wrapping method does it's best to B<only> do as much work as it
1823 absolutely needs to. In order to do this we have moved some of the
1824 performance costs to set-up time, where they are easier to amortize.
1826 All this said, our benchmarks have indicated the following:
1828 simple wrapper with no modifiers 100% slower
1829 simple wrapper with simple before modifier 400% slower
1830 simple wrapper with simple after modifier 450% slower
1831 simple wrapper with simple around modifier 500-550% slower
1832 simple wrapper with all 3 modifiers 1100% slower
1834 These numbers may seem daunting, but you must remember, every feature
1835 comes with some cost. To put things in perspective, just doing a
1836 simple C<AUTOLOAD> which does nothing but extract the name of the
1837 method called and return it costs about 400% over a normal method
1842 =item B<< $metaclass->add_before_method_modifier($method_name, $code) >>
1844 This wraps the specified method with the supplied subroutine
1845 reference. The modifier will be called as a method itself, and will
1846 receive the same arguments as are passed to the method.
1848 When the modifier exits, the wrapped method will be called.
1850 The return value of the modifier will be ignored.
1852 =item B<< $metaclass->add_after_method_modifier($method_name, $code) >>
1854 This wraps the specified method with the supplied subroutine
1855 reference. The modifier will be called as a method itself, and will
1856 receive the same arguments as are passed to the method.
1858 When the wrapped methods exits, the modifier will be called.
1860 The return value of the modifier will be ignored.
1862 =item B<< $metaclass->add_around_method_modifier($method_name, $code) >>
1864 This wraps the specified method with the supplied subroutine
1867 The first argument passed to the modifier will be a subroutine
1868 reference to the wrapped method. The second argument is the object,
1869 and after that come any arguments passed when the method is called.
1871 The around modifier can choose to call the original method, as well as
1872 what arguments to pass if it does so.
1874 The return value of the modifier is what will be seen by the caller.
1878 =head2 Introspection
1882 =item B<< Class::MOP::Class->meta >>
1884 This will return a L<Class::MOP::Class> instance for this class.
1886 It should also be noted that L<Class::MOP> will actually bootstrap
1887 this module by installing a number of attribute meta-objects into its
1894 Stevan Little E<lt>stevan@iinteractive.comE<gt>
1896 =head1 COPYRIGHT AND LICENSE
1898 Copyright 2006-2009 by Infinity Interactive, Inc.
1900 L<http://www.iinteractive.com>
1902 This library is free software; you can redistribute it and/or modify
1903 it under the same terms as Perl itself.