2 package Moose::Meta::Role;
8 use Sub::Name 'subname';
10 use Scalar::Util 'blessed', 'reftype';
12 our $VERSION = '0.12';
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;
135 sub _clean_up_required_methods {
137 foreach my $method ($self->get_required_method_list) {
138 $self->remove_required_methods($method)
139 if $self->has_method($method);
143 ## ------------------------------------------------------------------
147 # the before/around/after method modifiers are
148 # stored by name, but there can be many methods
149 # then associated with that name. So again we have
150 # lots of similar functionality, so we can do some
151 # meta-programmin' and save some time.
154 foreach my $modifier_type (qw[ before around after ]) {
156 my $attr_reader = "get_${modifier_type}_method_modifiers_map";
158 # create the attribute ...
159 $META->add_attribute("${modifier_type}_method_modifiers" => (
160 reader => $attr_reader,
161 default => sub { {} }
164 # and some helper methods ...
165 $META->add_method("get_${modifier_type}_method_modifiers" => sub {
166 my ($self, $method_name) = @_;
167 #return () unless exists $self->$attr_reader->{$method_name};
168 @{$self->$attr_reader->{$method_name}};
171 $META->add_method("has_${modifier_type}_method_modifiers" => sub {
172 my ($self, $method_name) = @_;
174 # for now we assume that if it exists,..
175 # it has at least one modifier in it
176 (exists $self->$attr_reader->{$method_name}) ? 1 : 0;
179 $META->add_method("add_${modifier_type}_method_modifier" => sub {
180 my ($self, $method_name, $method) = @_;
182 $self->$attr_reader->{$method_name} = []
183 unless exists $self->$attr_reader->{$method_name};
185 my $modifiers = $self->$attr_reader->{$method_name};
188 # check to see that we aren't adding the
189 # same code twice. We err in favor of the
190 # first on here, this may not be as expected
191 foreach my $modifier (@{$modifiers}) {
192 return if $modifier == $method;
195 push @{$modifiers} => $method;
200 ## ------------------------------------------------------------------
201 ## override method mofidiers
203 $META->add_attribute('override_method_modifiers' => (
204 reader => 'get_override_method_modifiers_map',
205 default => sub { {} }
209 # these are a little different because there
210 # can only be one per name, whereas the other
211 # method modifiers can have multiples.
214 sub add_override_method_modifier {
215 my ($self, $method_name, $method) = @_;
216 (!$self->has_method($method_name))
217 || confess "Cannot add an override of method '$method_name' " .
218 "because there is a local version of '$method_name'";
219 $self->get_override_method_modifiers_map->{$method_name} = $method;
222 sub has_override_method_modifier {
223 my ($self, $method_name) = @_;
225 # for now we assume that if it exists,..
226 # it has at least one modifier in it
227 (exists $self->get_override_method_modifiers_map->{$method_name}) ? 1 : 0;
230 sub get_override_method_modifier {
231 my ($self, $method_name) = @_;
232 $self->get_override_method_modifiers_map->{$method_name};
235 ## general list accessor ...
237 sub get_method_modifier_list {
238 my ($self, $modifier_type) = @_;
239 my $accessor = "get_${modifier_type}_method_modifiers_map";
240 keys %{$self->$accessor};
243 ## ------------------------------------------------------------------
246 __PACKAGE__->meta->add_attribute('roles' => (
247 reader => 'get_roles',
248 default => sub { [] }
252 my ($self, $role) = @_;
253 (blessed($role) && $role->isa('Moose::Meta::Role'))
254 || confess "Roles must be instances of Moose::Meta::Role";
255 push @{$self->get_roles} => $role;
258 sub calculate_all_roles {
264 $_->calculate_all_roles
265 } @{ $self->get_roles });
269 my ($self, $role_name) = @_;
271 || confess "You must supply a role name to look for";
272 # if we are it,.. then return true
273 return 1 if $role_name eq $self->name;
274 # otherwise.. check our children
275 foreach my $role (@{$self->get_roles}) {
276 return 1 if $role->does_role($role_name);
281 ## ------------------------------------------------------------------
284 sub method_metaclass { 'Moose::Meta::Role::Method' }
290 my $role_name = $self->name;
291 my $method_metaclass = $self->method_metaclass;
293 foreach my $symbol ($self->list_all_package_symbols('CODE')) {
295 my $code = $self->get_package_symbol('&' . $symbol);
297 my ($pkg, $name) = Class::MOP::get_code_info($code);
299 if ($pkg->can('meta')
301 # we don't know what ->meta we are calling
302 # here, so we need to be careful cause it
303 # just might blow up at us, or just complain
304 # loudly (in the case of Curses.pm) so we
305 # just be a little overly cautious here.
307 && eval { no warnings; blessed($pkg->meta) }
308 && $pkg->meta->isa('Moose::Meta::Role')) {
309 my $role = $pkg->meta->name;
310 next unless $self->does_role($role);
313 next if ($pkg || '') ne $role_name &&
314 ($name || '') ne '__ANON__';
317 $map->{$symbol} = $method_metaclass->wrap($code);
324 my ($self, $name) = @_;
325 $self->get_method_map->{$name}
329 my ($self, $name) = @_;
330 exists $self->get_method_map->{$name} ? 1 : 0
333 sub find_method_by_name { (shift)->get_method(@_) }
335 sub get_method_list {
337 grep { !/^meta$/ } keys %{$self->get_method_map};
341 my ($self, $method_name, $method) = @_;
342 (defined $method_name && $method_name)
343 || confess "You must define a method name";
345 my $body = (blessed($method) ? $method->body : $method);
346 ('CODE' eq (reftype($body) || ''))
347 || confess "Your code block must be a CODE reference";
349 $self->add_package_symbol("&${method_name}" => $body);
352 #sub reset_package_cache_flag { () }
353 #sub update_package_cache_flag { () }
355 ## ------------------------------------------------------------------
357 ## ------------------------------------------------------------------
360 my ($self, $other) = @_;
362 if ($other->isa('Moose::Meta::Role')) {
363 require Moose::Meta::Role::Application::ToRole;
364 return Moose::Meta::Role::Application::ToRole->new->apply($self, $other);
366 elsif ($other->isa('Moose::Meta::Class')) {
367 require Moose::Meta::Role::Application::ToClass;
368 return Moose::Meta::Role::Application::ToClass->new->apply($self, $other);
371 require Moose::Meta::Role::Application::ToInstance;
372 return Moose::Meta::Role::Application::ToInstance->new->apply($self, $other);
377 my ($class, @roles) = @_;
379 require Moose::Meta::Role::Application::RoleSummation;
380 require Moose::Meta::Role::Composite;
382 my $c = Moose::Meta::Role::Composite->new(roles => \@roles);
383 Moose::Meta::Role::Application::RoleSummation->new->apply($c);
387 #####################################################################
389 ## This is Moose::Meta::Role as defined by Moose (plus the use of
390 ## MooseX::AttributeHelpers module). It is here as a reference to
391 ## make it easier to see what is happening above with all the meta
393 #####################################################################
396 # metaclass => 'Collection::Array',
397 # reader => 'get_roles',
398 # isa => 'ArrayRef[Moose::Meta::Roles]',
399 # default => sub { [] },
401 # 'push' => 'add_role',
405 # has 'excluded_roles_map' => (
406 # metaclass => 'Collection::Hash',
407 # reader => 'get_excluded_roles_map',
408 # isa => 'HashRef[Str]',
410 # # Not exactly set, cause it sets multiple
411 # 'set' => 'add_excluded_roles',
412 # 'keys' => 'get_excluded_roles_list',
413 # 'exists' => 'excludes_role',
417 # has 'attribute_map' => (
418 # metaclass => 'Collection::Hash',
419 # reader => 'get_attribute_map',
420 # isa => 'HashRef[Str]',
422 # # 'set' => 'add_attribute' # has some special crap in it
423 # 'get' => 'get_attribute',
424 # 'keys' => 'get_attribute_list',
425 # 'exists' => 'has_attribute',
426 # # Not exactly delete, cause it sets multiple
427 # 'delete' => 'remove_attribute',
431 # has 'required_methods' => (
432 # metaclass => 'Collection::Hash',
433 # reader => 'get_required_methods_map',
434 # isa => 'HashRef[Str]',
436 # # not exactly set, or delete since it works for multiple
437 # 'set' => 'add_required_methods',
438 # 'delete' => 'remove_required_methods',
439 # 'keys' => 'get_required_method_list',
440 # 'exists' => 'requires_method',
444 # # the before, around and after modifiers are
445 # # HASH keyed by method-name, with ARRAY of
446 # # CODE refs to apply in that order
448 # has 'before_method_modifiers' => (
449 # metaclass => 'Collection::Hash',
450 # reader => 'get_before_method_modifiers_map',
451 # isa => 'HashRef[ArrayRef[CodeRef]]',
453 # 'keys' => 'get_before_method_modifiers',
454 # 'exists' => 'has_before_method_modifiers',
455 # # This actually makes sure there is an
456 # # ARRAY at the given key, and pushed onto
457 # # it. It also checks for duplicates as well
458 # # 'add' => 'add_before_method_modifier'
462 # has 'after_method_modifiers' => (
463 # metaclass => 'Collection::Hash',
464 # reader =>'get_after_method_modifiers_map',
465 # isa => 'HashRef[ArrayRef[CodeRef]]',
467 # 'keys' => 'get_after_method_modifiers',
468 # 'exists' => 'has_after_method_modifiers',
469 # # This actually makes sure there is an
470 # # ARRAY at the given key, and pushed onto
471 # # it. It also checks for duplicates as well
472 # # 'add' => 'add_after_method_modifier'
476 # has 'around_method_modifiers' => (
477 # metaclass => 'Collection::Hash',
478 # reader =>'get_around_method_modifiers_map',
479 # isa => 'HashRef[ArrayRef[CodeRef]]',
481 # 'keys' => 'get_around_method_modifiers',
482 # 'exists' => 'has_around_method_modifiers',
483 # # This actually makes sure there is an
484 # # ARRAY at the given key, and pushed onto
485 # # it. It also checks for duplicates as well
486 # # 'add' => 'add_around_method_modifier'
490 # # override is similar to the other modifiers
491 # # except that it is not an ARRAY of code refs
492 # # but instead just a single name->code mapping
494 # has 'override_method_modifiers' => (
495 # metaclass => 'Collection::Hash',
496 # reader =>'get_override_method_modifiers_map',
497 # isa => 'HashRef[CodeRef]',
499 # 'keys' => 'get_override_method_modifier',
500 # 'exists' => 'has_override_method_modifier',
501 # 'add' => 'add_override_method_modifier', # checks for local method ..
505 #####################################################################
516 Moose::Meta::Role - The Moose Role metaclass
520 Please see L<Moose::Role> for more information about roles.
521 For the most part, this has no user-serviceable parts inside
522 this module. It's API is still subject to some change (although
523 probably not that much really).
561 =item B<add_excluded_roles>
563 =item B<excludes_role>
565 =item B<get_excluded_roles_list>
567 =item B<get_excluded_roles_map>
569 =item B<calculate_all_roles>
575 =item B<method_metaclass>
577 =item B<find_method_by_name>
583 =item B<alias_method>
585 =item B<get_method_list>
587 =item B<get_method_map>
589 =item B<update_package_cache_flag>
591 =item B<reset_package_cache_flag>
597 =item B<add_attribute>
599 =item B<has_attribute>
601 =item B<get_attribute>
603 =item B<get_attribute_list>
605 =item B<get_attribute_map>
607 =item B<remove_attribute>
613 =item B<add_required_methods>
615 =item B<remove_required_methods>
617 =item B<get_required_method_list>
619 =item B<get_required_methods_map>
621 =item B<requires_method>
627 =item B<add_after_method_modifier>
629 =item B<add_around_method_modifier>
631 =item B<add_before_method_modifier>
633 =item B<add_override_method_modifier>
639 =item B<has_after_method_modifiers>
641 =item B<has_around_method_modifiers>
643 =item B<has_before_method_modifiers>
645 =item B<has_override_method_modifier>
651 =item B<get_after_method_modifiers>
653 =item B<get_around_method_modifiers>
655 =item B<get_before_method_modifiers>
657 =item B<get_method_modifier_list>
663 =item B<get_override_method_modifier>
665 =item B<get_after_method_modifiers_map>
667 =item B<get_around_method_modifiers_map>
669 =item B<get_before_method_modifiers_map>
671 =item B<get_override_method_modifiers_map>
677 All complex software has bugs lurking in it, and this module is no
678 exception. If you find a bug please either email me, or add the bug
683 Stevan Little E<lt>stevan@iinteractive.comE<gt>
685 =head1 COPYRIGHT AND LICENSE
687 Copyright 2006, 2007 by Infinity Interactive, Inc.
689 L<http://www.iinteractive.com>
691 This library is free software; you can redistribute it and/or modify
692 it under the same terms as Perl itself.