2 package Moose::Meta::Role;
9 use Scalar::Util 'blessed';
11 our $VERSION = '0.56';
12 $VERSION = eval $VERSION;
13 our $AUTHORITY = 'cpan:STEVAN';
15 use Moose::Meta::Class;
16 use Moose::Meta::Role::Method;
17 use Moose::Meta::Role::Method::Required;
19 use base 'Class::MOP::Module';
21 ## ------------------------------------------------------------------
23 ## I normally don't do this, but I am doing
24 ## a whole bunch of meta-programmin in this
25 ## module, so it just makes sense. For a clearer
26 ## picture of what is going on in the next
27 ## several lines of code, look at the really
28 ## big comment at the end of this file (right
31 ## ------------------------------------------------------------------
33 my $META = __PACKAGE__->meta;
35 ## ------------------------------------------------------------------
39 # since roles are lazy, we hold all the attributes
40 # of the individual role in 'statis' until which
41 # time when it is applied to a class. This means
42 # keeping a lot of things in hash maps, so we are
43 # using a little of that meta-programmin' magic
44 # here an saving lots of extra typin. And since
45 # many of these attributes above require similar
46 # functionality to support them, so we again use
47 # the wonders of meta-programmin' to deliver a
48 # very compact solution to this normally verbose
54 name => 'excluded_roles_map',
55 attr_reader => 'get_excluded_roles_map' ,
57 add => 'add_excluded_roles',
58 get_list => 'get_excluded_roles_list',
59 existence => 'excludes_role',
63 name => 'required_methods',
64 attr_reader => 'get_required_methods_map',
66 add => 'add_required_methods',
67 remove => 'remove_required_methods',
68 get_list => 'get_required_method_list',
69 existence => 'requires_method',
73 name => 'attribute_map',
74 attr_reader => 'get_attribute_map',
76 get => 'get_attribute',
77 get_list => 'get_attribute_list',
78 existence => 'has_attribute',
79 remove => 'remove_attribute',
84 my $attr_reader = $action->{attr_reader};
85 my $methods = $action->{methods};
87 # create the attribute
88 $META->add_attribute($action->{name} => (
89 reader => $attr_reader,
93 # create some helper methods
94 $META->add_method($methods->{add} => sub {
95 my ($self, @values) = @_;
96 $self->$attr_reader->{$_} = undef foreach @values;
97 }) if exists $methods->{add};
99 $META->add_method($methods->{get_list} => sub {
101 keys %{$self->$attr_reader};
102 }) if exists $methods->{get_list};
104 $META->add_method($methods->{get} => sub {
105 my ($self, $name) = @_;
106 $self->$attr_reader->{$name}
107 }) if exists $methods->{get};
109 $META->add_method($methods->{existence} => sub {
110 my ($self, $name) = @_;
111 exists $self->$attr_reader->{$name} ? 1 : 0;
112 }) if exists $methods->{existence};
114 $META->add_method($methods->{remove} => sub {
115 my ($self, @values) = @_;
116 delete $self->$attr_reader->{$_} foreach @values;
117 }) if exists $methods->{remove};
120 ## some things don't always fit, so they go here ...
126 if (scalar @_ == 1 && ref($_[0]) eq 'HASH') {
132 $self->get_attribute_map->{$name} = $attr_desc;
136 # sub _clean_up_required_methods {
138 # foreach my $method ($self->get_required_method_list) {
139 # $self->remove_required_methods($method)
140 # if $self->has_method($method);
144 ## ------------------------------------------------------------------
148 # the before/around/after method modifiers are
149 # stored by name, but there can be many methods
150 # then associated with that name. So again we have
151 # lots of similar functionality, so we can do some
152 # meta-programmin' and save some time.
155 foreach my $modifier_type (qw[ before around after ]) {
157 my $attr_reader = "get_${modifier_type}_method_modifiers_map";
159 # create the attribute ...
160 $META->add_attribute("${modifier_type}_method_modifiers" => (
161 reader => $attr_reader,
162 default => sub { {} }
165 # and some helper methods ...
166 $META->add_method("get_${modifier_type}_method_modifiers" => sub {
167 my ($self, $method_name) = @_;
168 #return () unless exists $self->$attr_reader->{$method_name};
169 @{$self->$attr_reader->{$method_name}};
172 $META->add_method("has_${modifier_type}_method_modifiers" => sub {
173 my ($self, $method_name) = @_;
175 # for now we assume that if it exists,..
176 # it has at least one modifier in it
177 (exists $self->$attr_reader->{$method_name}) ? 1 : 0;
180 $META->add_method("add_${modifier_type}_method_modifier" => sub {
181 my ($self, $method_name, $method) = @_;
183 $self->$attr_reader->{$method_name} = []
184 unless exists $self->$attr_reader->{$method_name};
186 my $modifiers = $self->$attr_reader->{$method_name};
189 # check to see that we aren't adding the
190 # same code twice. We err in favor of the
191 # first on here, this may not be as expected
192 foreach my $modifier (@{$modifiers}) {
193 return if $modifier == $method;
196 push @{$modifiers} => $method;
201 ## ------------------------------------------------------------------
202 ## override method mofidiers
204 $META->add_attribute('override_method_modifiers' => (
205 reader => 'get_override_method_modifiers_map',
206 default => sub { {} }
210 # these are a little different because there
211 # can only be one per name, whereas the other
212 # method modifiers can have multiples.
215 sub add_override_method_modifier {
216 my ($self, $method_name, $method) = @_;
217 (!$self->has_method($method_name))
218 || confess "Cannot add an override of method '$method_name' " .
219 "because there is a local version of '$method_name'";
220 $self->get_override_method_modifiers_map->{$method_name} = $method;
223 sub has_override_method_modifier {
224 my ($self, $method_name) = @_;
226 # for now we assume that if it exists,..
227 # it has at least one modifier in it
228 (exists $self->get_override_method_modifiers_map->{$method_name}) ? 1 : 0;
231 sub get_override_method_modifier {
232 my ($self, $method_name) = @_;
233 $self->get_override_method_modifiers_map->{$method_name};
236 ## general list accessor ...
238 sub get_method_modifier_list {
239 my ($self, $modifier_type) = @_;
240 my $accessor = "get_${modifier_type}_method_modifiers_map";
241 keys %{$self->$accessor};
244 sub reset_package_cache_flag { (shift)->{'_package_cache_flag'} = undef }
245 sub update_package_cache_flag {
247 $self->{'_package_cache_flag'} = Class::MOP::check_package_cache_flag($self->name);
252 ## ------------------------------------------------------------------
255 __PACKAGE__->meta->add_attribute('roles' => (
256 reader => 'get_roles',
257 default => sub { [] }
261 my ($self, $role) = @_;
262 (blessed($role) && $role->isa('Moose::Meta::Role'))
263 || confess "Roles must be instances of Moose::Meta::Role";
264 push @{$self->get_roles} => $role;
265 $self->reset_package_cache_flag;
268 sub calculate_all_roles {
274 $_->calculate_all_roles
275 } @{ $self->get_roles });
279 my ($self, $role_name) = @_;
281 || confess "You must supply a role name to look for";
282 # if we are it,.. then return true
283 return 1 if $role_name eq $self->name;
284 # otherwise.. check our children
285 foreach my $role (@{$self->get_roles}) {
286 return 1 if $role->does_role($role_name);
291 ## ------------------------------------------------------------------
294 sub method_metaclass { 'Moose::Meta::Role::Method' }
299 my $current = Class::MOP::check_package_cache_flag($self->name);
301 if (defined $self->{'_package_cache_flag'} && $self->{'_package_cache_flag'} == $current) {
302 return $self->{'methods'} ||= {};
305 $self->{_package_cache_flag} = $current;
307 my $map = $self->{'methods'} ||= {};
309 my $role_name = $self->name;
310 my $method_metaclass = $self->method_metaclass;
312 my %all_code = $self->get_all_package_symbols('CODE');
314 foreach my $symbol (keys %all_code) {
315 my $code = $all_code{$symbol};
317 next if exists $map->{$symbol} &&
318 defined $map->{$symbol} &&
319 $map->{$symbol}->body == $code;
321 my ($pkg, $name) = Class::MOP::get_code_info($code);
323 if ($pkg->can('meta')
325 # we don't know what ->meta we are calling
326 # here, so we need to be careful cause it
327 # just might blow up at us, or just complain
328 # loudly (in the case of Curses.pm) so we
329 # just be a little overly cautious here.
331 && eval { no warnings; blessed($pkg->meta) } # FIXME calls meta
332 && $pkg->meta->isa('Moose::Meta::Role')) {
333 my $role = $pkg->meta->name;
334 next unless $self->does_role($role);
338 # in 5.10 constant.pm the constants show up
339 # as being in the right package, but in pre-5.10
340 # they show up as constant::__ANON__ so we
341 # make an exception here to be sure that things
342 # work as expected in both.
344 unless ($pkg eq 'constant' && $name eq '__ANON__') {
345 next if ($pkg || '') ne $role_name ||
346 (($name || '') ne '__ANON__' && ($pkg || '') ne $role_name);
350 $map->{$symbol} = $method_metaclass->wrap(
352 package_name => $role_name,
361 my ($self, $name) = @_;
362 $self->get_method_map->{$name};
366 my ($self, $name) = @_;
367 exists $self->get_method_map->{$name} ? 1 : 0
370 # FIXME this is copypasated from Class::MOP::Class
371 # refactor to inherit from some common base
372 sub wrap_method_body {
373 my ( $self, %args ) = @_;
375 my $body = delete $args{body}; # delete is for compat
377 ('CODE' eq ref($body))
378 || confess "Your code block must be a CODE reference";
380 $self->method_metaclass->wrap( $body => (
381 package_name => $self->name,
387 my ($self, $method_name, $method) = @_;
388 (defined $method_name && $method_name)
389 || confess "You must define a method name";
392 if (blessed($method)) {
393 $body = $method->body;
394 if ($method->package_name ne $self->name &&
395 $method->name ne $method_name) {
396 warn "Hello there, got something for you."
397 . " Method says " . $method->package_name . " " . $method->name
398 . " Class says " . $self->name . " " . $method_name;
399 $method = $method->clone(
400 package_name => $self->name,
402 ) if $method->can('clone');
407 $method = $self->wrap_method_body( body => $body, name => $method_name );
410 $method->attach_to_class($self);
412 $self->get_method_map->{$method_name} = $method;
414 my $full_method_name = ($self->name . '::' . $method_name);
415 $self->add_package_symbol(
416 { sigil => '&', type => 'CODE', name => $method_name },
417 Class::MOP::subname($full_method_name => $body)
420 $self->update_package_cache_flag; # still valid, since we just added the method to the map, and if it was invalid before that then get_method_map updated it
423 sub find_method_by_name { (shift)->get_method(@_) }
425 sub get_method_list {
427 grep { !/^meta$/ } keys %{$self->get_method_map};
431 my ($self, $method_name, $method) = @_;
432 (defined $method_name && $method_name)
433 || confess "You must define a method name";
435 my $body = (blessed($method) ? $method->body : $method);
436 ('CODE' eq ref($body))
437 || confess "Your code block must be a CODE reference";
439 $self->add_package_symbol(
440 { sigil => '&', type => 'CODE', name => $method_name },
445 ## ------------------------------------------------------------------
447 ## ------------------------------------------------------------------
450 my ($self, $other, @args) = @_;
453 || confess "You must pass in an blessed instance";
455 if ($other->isa('Moose::Meta::Role')) {
456 require Moose::Meta::Role::Application::ToRole;
457 return Moose::Meta::Role::Application::ToRole->new(@args)->apply($self, $other);
459 elsif ($other->isa('Moose::Meta::Class')) {
460 require Moose::Meta::Role::Application::ToClass;
461 return Moose::Meta::Role::Application::ToClass->new(@args)->apply($self, $other);
464 require Moose::Meta::Role::Application::ToInstance;
465 return Moose::Meta::Role::Application::ToInstance->new(@args)->apply($self, $other);
470 my ($class, @role_specs) = @_;
472 require Moose::Meta::Role::Application::RoleSummation;
473 require Moose::Meta::Role::Composite;
475 my (@roles, %role_params);
476 while (@role_specs) {
477 my ($role, $params) = @{ splice @role_specs, 0, 1 };
478 push @roles => $role->meta;
479 next unless defined $params;
480 $role_params{$role} = $params;
483 my $c = Moose::Meta::Role::Composite->new(roles => \@roles);
484 Moose::Meta::Role::Application::RoleSummation->new(
485 role_params => \%role_params
491 #####################################################################
493 ## This is Moose::Meta::Role as defined by Moose (plus the use of
494 ## MooseX::AttributeHelpers module). It is here as a reference to
495 ## make it easier to see what is happening above with all the meta
497 #####################################################################
500 # metaclass => 'Collection::Array',
501 # reader => 'get_roles',
502 # isa => 'ArrayRef[Moose::Meta::Roles]',
503 # default => sub { [] },
505 # 'push' => 'add_role',
509 # has 'excluded_roles_map' => (
510 # metaclass => 'Collection::Hash',
511 # reader => 'get_excluded_roles_map',
512 # isa => 'HashRef[Str]',
514 # # Not exactly set, cause it sets multiple
515 # 'set' => 'add_excluded_roles',
516 # 'keys' => 'get_excluded_roles_list',
517 # 'exists' => 'excludes_role',
521 # has 'attribute_map' => (
522 # metaclass => 'Collection::Hash',
523 # reader => 'get_attribute_map',
524 # isa => 'HashRef[Str]',
526 # # 'set' => 'add_attribute' # has some special crap in it
527 # 'get' => 'get_attribute',
528 # 'keys' => 'get_attribute_list',
529 # 'exists' => 'has_attribute',
530 # # Not exactly delete, cause it sets multiple
531 # 'delete' => 'remove_attribute',
535 # has 'required_methods' => (
536 # metaclass => 'Collection::Hash',
537 # reader => 'get_required_methods_map',
538 # isa => 'HashRef[Str]',
540 # # not exactly set, or delete since it works for multiple
541 # 'set' => 'add_required_methods',
542 # 'delete' => 'remove_required_methods',
543 # 'keys' => 'get_required_method_list',
544 # 'exists' => 'requires_method',
548 # # the before, around and after modifiers are
549 # # HASH keyed by method-name, with ARRAY of
550 # # CODE refs to apply in that order
552 # has 'before_method_modifiers' => (
553 # metaclass => 'Collection::Hash',
554 # reader => 'get_before_method_modifiers_map',
555 # isa => 'HashRef[ArrayRef[CodeRef]]',
557 # 'keys' => 'get_before_method_modifiers',
558 # 'exists' => 'has_before_method_modifiers',
559 # # This actually makes sure there is an
560 # # ARRAY at the given key, and pushed onto
561 # # it. It also checks for duplicates as well
562 # # 'add' => 'add_before_method_modifier'
566 # has 'after_method_modifiers' => (
567 # metaclass => 'Collection::Hash',
568 # reader =>'get_after_method_modifiers_map',
569 # isa => 'HashRef[ArrayRef[CodeRef]]',
571 # 'keys' => 'get_after_method_modifiers',
572 # 'exists' => 'has_after_method_modifiers',
573 # # This actually makes sure there is an
574 # # ARRAY at the given key, and pushed onto
575 # # it. It also checks for duplicates as well
576 # # 'add' => 'add_after_method_modifier'
580 # has 'around_method_modifiers' => (
581 # metaclass => 'Collection::Hash',
582 # reader =>'get_around_method_modifiers_map',
583 # isa => 'HashRef[ArrayRef[CodeRef]]',
585 # 'keys' => 'get_around_method_modifiers',
586 # 'exists' => 'has_around_method_modifiers',
587 # # This actually makes sure there is an
588 # # ARRAY at the given key, and pushed onto
589 # # it. It also checks for duplicates as well
590 # # 'add' => 'add_around_method_modifier'
594 # # override is similar to the other modifiers
595 # # except that it is not an ARRAY of code refs
596 # # but instead just a single name->code mapping
598 # has 'override_method_modifiers' => (
599 # metaclass => 'Collection::Hash',
600 # reader =>'get_override_method_modifiers_map',
601 # isa => 'HashRef[CodeRef]',
603 # 'keys' => 'get_override_method_modifier',
604 # 'exists' => 'has_override_method_modifier',
605 # 'add' => 'add_override_method_modifier', # checks for local method ..
609 #####################################################################
620 Moose::Meta::Role - The Moose Role metaclass
624 Please see L<Moose::Role> for more information about roles.
625 For the most part, this has no user-serviceable parts inside
626 this module. It's API is still subject to some change (although
627 probably not that much really).
639 =item B<apply_to_metaclass_instance>
667 =item B<add_excluded_roles>
669 =item B<excludes_role>
671 =item B<get_excluded_roles_list>
673 =item B<get_excluded_roles_map>
675 =item B<calculate_all_roles>
681 =item B<method_metaclass>
683 =item B<find_method_by_name>
691 =item B<wrap_method_body>
693 =item B<alias_method>
695 =item B<get_method_list>
697 =item B<get_method_map>
699 =item B<update_package_cache_flag>
701 =item B<reset_package_cache_flag>
707 =item B<add_attribute>
709 =item B<has_attribute>
711 =item B<get_attribute>
713 =item B<get_attribute_list>
715 =item B<get_attribute_map>
717 =item B<remove_attribute>
723 =item B<add_required_methods>
725 =item B<remove_required_methods>
727 =item B<get_required_method_list>
729 =item B<get_required_methods_map>
731 =item B<requires_method>
737 =item B<add_after_method_modifier>
739 =item B<add_around_method_modifier>
741 =item B<add_before_method_modifier>
743 =item B<add_override_method_modifier>
749 =item B<has_after_method_modifiers>
751 =item B<has_around_method_modifiers>
753 =item B<has_before_method_modifiers>
755 =item B<has_override_method_modifier>
761 =item B<get_after_method_modifiers>
763 =item B<get_around_method_modifiers>
765 =item B<get_before_method_modifiers>
767 =item B<get_method_modifier_list>
773 =item B<get_override_method_modifier>
775 =item B<get_after_method_modifiers_map>
777 =item B<get_around_method_modifiers_map>
779 =item B<get_before_method_modifiers_map>
781 =item B<get_override_method_modifiers_map>
787 All complex software has bugs lurking in it, and this module is no
788 exception. If you find a bug please either email me, or add the bug
793 Stevan Little E<lt>stevan@iinteractive.comE<gt>
795 =head1 COPYRIGHT AND LICENSE
797 Copyright 2006-2008 by Infinity Interactive, Inc.
799 L<http://www.iinteractive.com>
801 This library is free software; you can redistribute it and/or modify
802 it under the same terms as Perl itself.