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;
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 ## ------------------------------------------------------------------
247 __PACKAGE__->meta->add_attribute('roles' => (
248 reader => 'get_roles',
249 default => sub { [] }
253 my ($self, $role) = @_;
254 (blessed($role) && $role->isa('Moose::Meta::Role'))
255 || confess "Roles must be instances of Moose::Meta::Role";
256 push @{$self->get_roles} => $role;
259 sub calculate_all_roles {
265 $_->calculate_all_roles
266 } @{ $self->get_roles });
270 my ($self, $role_name) = @_;
272 || confess "You must supply a role name to look for";
273 # if we are it,.. then return true
274 return 1 if $role_name eq $self->name;
275 # otherwise.. check our children
276 foreach my $role (@{$self->get_roles}) {
277 return 1 if $role->does_role($role_name);
282 ## ------------------------------------------------------------------
285 sub method_metaclass { 'Moose::Meta::Role::Method' }
291 my $role_name = $self->name;
292 my $method_metaclass = $self->method_metaclass;
294 foreach my $symbol ($self->list_all_package_symbols('CODE')) {
296 my $code = $self->get_package_symbol('&' . $symbol);
298 my ($pkg, $name) = Class::MOP::get_code_info($code);
300 if ($pkg->can('meta')
302 # we don't know what ->meta we are calling
303 # here, so we need to be careful cause it
304 # just might blow up at us, or just complain
305 # loudly (in the case of Curses.pm) so we
306 # just be a little overly cautious here.
308 && eval { no warnings; blessed($pkg->meta) }
309 && $pkg->meta->isa('Moose::Meta::Role')) {
310 my $role = $pkg->meta->name;
311 next unless $self->does_role($role);
314 next if ($pkg || '') ne $role_name &&
315 ($name || '') ne '__ANON__';
318 $map->{$symbol} = $method_metaclass->wrap($code);
325 my ($self, $name) = @_;
326 $self->get_method_map->{$name};
330 my ($self, $name) = @_;
331 exists $self->get_method_map->{$name} ? 1 : 0
334 sub find_method_by_name { (shift)->get_method(@_) }
336 sub get_method_list {
338 grep { !/^meta$/ } keys %{$self->get_method_map};
342 my ($self, $method_name, $method) = @_;
343 (defined $method_name && $method_name)
344 || confess "You must define a method name";
346 my $body = (blessed($method) ? $method->body : $method);
347 ('CODE' eq (reftype($body) || ''))
348 || confess "Your code block must be a CODE reference";
350 $self->add_package_symbol("&${method_name}" => $body);
353 ## ------------------------------------------------------------------
355 ## ------------------------------------------------------------------
358 my ($self, $other, @args) = @_;
361 || confess "You must pass in an blessed instance";
363 if ($other->isa('Moose::Meta::Role')) {
364 require Moose::Meta::Role::Application::ToRole;
365 return Moose::Meta::Role::Application::ToRole->new(@args)->apply($self, $other);
367 elsif ($other->isa('Moose::Meta::Class')) {
368 require Moose::Meta::Role::Application::ToClass;
369 return Moose::Meta::Role::Application::ToClass->new(@args)->apply($self, $other);
372 require Moose::Meta::Role::Application::ToInstance;
373 return Moose::Meta::Role::Application::ToInstance->new(@args)->apply($self, $other);
378 my ($class, @role_specs) = @_;
380 require Moose::Meta::Role::Application::RoleSummation;
381 require Moose::Meta::Role::Composite;
383 my (@roles, %role_params);
384 while (@role_specs) {
385 my ($role, $params) = @{ splice @role_specs, 0, 1 };
386 push @roles => $role->meta;
387 next unless defined $params;
388 $role_params{$role} = $params;
391 my $c = Moose::Meta::Role::Composite->new(roles => \@roles);
392 Moose::Meta::Role::Application::RoleSummation->new(
393 role_params => \%role_params
399 #####################################################################
401 ## This is Moose::Meta::Role as defined by Moose (plus the use of
402 ## MooseX::AttributeHelpers module). It is here as a reference to
403 ## make it easier to see what is happening above with all the meta
405 #####################################################################
408 # metaclass => 'Collection::Array',
409 # reader => 'get_roles',
410 # isa => 'ArrayRef[Moose::Meta::Roles]',
411 # default => sub { [] },
413 # 'push' => 'add_role',
417 # has 'excluded_roles_map' => (
418 # metaclass => 'Collection::Hash',
419 # reader => 'get_excluded_roles_map',
420 # isa => 'HashRef[Str]',
422 # # Not exactly set, cause it sets multiple
423 # 'set' => 'add_excluded_roles',
424 # 'keys' => 'get_excluded_roles_list',
425 # 'exists' => 'excludes_role',
429 # has 'attribute_map' => (
430 # metaclass => 'Collection::Hash',
431 # reader => 'get_attribute_map',
432 # isa => 'HashRef[Str]',
434 # # 'set' => 'add_attribute' # has some special crap in it
435 # 'get' => 'get_attribute',
436 # 'keys' => 'get_attribute_list',
437 # 'exists' => 'has_attribute',
438 # # Not exactly delete, cause it sets multiple
439 # 'delete' => 'remove_attribute',
443 # has 'required_methods' => (
444 # metaclass => 'Collection::Hash',
445 # reader => 'get_required_methods_map',
446 # isa => 'HashRef[Str]',
448 # # not exactly set, or delete since it works for multiple
449 # 'set' => 'add_required_methods',
450 # 'delete' => 'remove_required_methods',
451 # 'keys' => 'get_required_method_list',
452 # 'exists' => 'requires_method',
456 # # the before, around and after modifiers are
457 # # HASH keyed by method-name, with ARRAY of
458 # # CODE refs to apply in that order
460 # has 'before_method_modifiers' => (
461 # metaclass => 'Collection::Hash',
462 # reader => 'get_before_method_modifiers_map',
463 # isa => 'HashRef[ArrayRef[CodeRef]]',
465 # 'keys' => 'get_before_method_modifiers',
466 # 'exists' => 'has_before_method_modifiers',
467 # # This actually makes sure there is an
468 # # ARRAY at the given key, and pushed onto
469 # # it. It also checks for duplicates as well
470 # # 'add' => 'add_before_method_modifier'
474 # has 'after_method_modifiers' => (
475 # metaclass => 'Collection::Hash',
476 # reader =>'get_after_method_modifiers_map',
477 # isa => 'HashRef[ArrayRef[CodeRef]]',
479 # 'keys' => 'get_after_method_modifiers',
480 # 'exists' => 'has_after_method_modifiers',
481 # # This actually makes sure there is an
482 # # ARRAY at the given key, and pushed onto
483 # # it. It also checks for duplicates as well
484 # # 'add' => 'add_after_method_modifier'
488 # has 'around_method_modifiers' => (
489 # metaclass => 'Collection::Hash',
490 # reader =>'get_around_method_modifiers_map',
491 # isa => 'HashRef[ArrayRef[CodeRef]]',
493 # 'keys' => 'get_around_method_modifiers',
494 # 'exists' => 'has_around_method_modifiers',
495 # # This actually makes sure there is an
496 # # ARRAY at the given key, and pushed onto
497 # # it. It also checks for duplicates as well
498 # # 'add' => 'add_around_method_modifier'
502 # # override is similar to the other modifiers
503 # # except that it is not an ARRAY of code refs
504 # # but instead just a single name->code mapping
506 # has 'override_method_modifiers' => (
507 # metaclass => 'Collection::Hash',
508 # reader =>'get_override_method_modifiers_map',
509 # isa => 'HashRef[CodeRef]',
511 # 'keys' => 'get_override_method_modifier',
512 # 'exists' => 'has_override_method_modifier',
513 # 'add' => 'add_override_method_modifier', # checks for local method ..
517 #####################################################################
528 Moose::Meta::Role - The Moose Role metaclass
532 Please see L<Moose::Role> for more information about roles.
533 For the most part, this has no user-serviceable parts inside
534 this module. It's API is still subject to some change (although
535 probably not that much really).
573 =item B<add_excluded_roles>
575 =item B<excludes_role>
577 =item B<get_excluded_roles_list>
579 =item B<get_excluded_roles_map>
581 =item B<calculate_all_roles>
587 =item B<method_metaclass>
589 =item B<find_method_by_name>
595 =item B<alias_method>
597 =item B<get_method_list>
599 =item B<get_method_map>
601 =item B<update_package_cache_flag>
603 =item B<reset_package_cache_flag>
609 =item B<add_attribute>
611 =item B<has_attribute>
613 =item B<get_attribute>
615 =item B<get_attribute_list>
617 =item B<get_attribute_map>
619 =item B<remove_attribute>
625 =item B<add_required_methods>
627 =item B<remove_required_methods>
629 =item B<get_required_method_list>
631 =item B<get_required_methods_map>
633 =item B<requires_method>
639 =item B<add_after_method_modifier>
641 =item B<add_around_method_modifier>
643 =item B<add_before_method_modifier>
645 =item B<add_override_method_modifier>
651 =item B<has_after_method_modifiers>
653 =item B<has_around_method_modifiers>
655 =item B<has_before_method_modifiers>
657 =item B<has_override_method_modifier>
663 =item B<get_after_method_modifiers>
665 =item B<get_around_method_modifiers>
667 =item B<get_before_method_modifiers>
669 =item B<get_method_modifier_list>
675 =item B<get_override_method_modifier>
677 =item B<get_after_method_modifiers_map>
679 =item B<get_around_method_modifiers_map>
681 =item B<get_before_method_modifiers_map>
683 =item B<get_override_method_modifiers_map>
689 All complex software has bugs lurking in it, and this module is no
690 exception. If you find a bug please either email me, or add the bug
695 Stevan Little E<lt>stevan@iinteractive.comE<gt>
697 =head1 COPYRIGHT AND LICENSE
699 Copyright 2006-2008 by Infinity Interactive, Inc.
701 L<http://www.iinteractive.com>
703 This library is free software; you can redistribute it and/or modify
704 it under the same terms as Perl itself.