2 package Moose::Meta::Role;
8 use Scalar::Util 'blessed';
10 our $VERSION = '0.57';
11 $VERSION = eval $VERSION;
12 our $AUTHORITY = 'cpan:STEVAN';
14 use Moose::Meta::Class;
15 use Moose::Meta::Role::Method;
16 use Moose::Meta::Role::Method::Required;
18 use base 'Class::MOP::Module';
20 ## ------------------------------------------------------------------
22 ## I normally don't do this, but I am doing
23 ## a whole bunch of meta-programmin in this
24 ## module, so it just makes sense. For a clearer
25 ## picture of what is going on in the next
26 ## several lines of code, look at the really
27 ## big comment at the end of this file (right
30 ## ------------------------------------------------------------------
32 my $META = __PACKAGE__->meta;
34 ## ------------------------------------------------------------------
38 # since roles are lazy, we hold all the attributes
39 # of the individual role in 'statis' until which
40 # time when it is applied to a class. This means
41 # keeping a lot of things in hash maps, so we are
42 # using a little of that meta-programmin' magic
43 # here an saving lots of extra typin. And since
44 # many of these attributes above require similar
45 # functionality to support them, so we again use
46 # the wonders of meta-programmin' to deliver a
47 # very compact solution to this normally verbose
53 name => 'excluded_roles_map',
54 attr_reader => 'get_excluded_roles_map' ,
56 add => 'add_excluded_roles',
57 get_list => 'get_excluded_roles_list',
58 existence => 'excludes_role',
62 name => 'required_methods',
63 attr_reader => 'get_required_methods_map',
65 add => 'add_required_methods',
66 remove => 'remove_required_methods',
67 get_list => 'get_required_method_list',
68 existence => 'requires_method',
72 name => 'attribute_map',
73 attr_reader => 'get_attribute_map',
75 get => 'get_attribute',
76 get_list => 'get_attribute_list',
77 existence => 'has_attribute',
78 remove => 'remove_attribute',
83 my $attr_reader = $action->{attr_reader};
84 my $methods = $action->{methods};
86 # create the attribute
87 $META->add_attribute($action->{name} => (
88 reader => $attr_reader,
92 # create some helper methods
93 $META->add_method($methods->{add} => sub {
94 my ($self, @values) = @_;
95 $self->$attr_reader->{$_} = undef foreach @values;
96 }) if exists $methods->{add};
98 $META->add_method($methods->{get_list} => sub {
100 keys %{$self->$attr_reader};
101 }) if exists $methods->{get_list};
103 $META->add_method($methods->{get} => sub {
104 my ($self, $name) = @_;
105 $self->$attr_reader->{$name}
106 }) if exists $methods->{get};
108 $META->add_method($methods->{existence} => sub {
109 my ($self, $name) = @_;
110 exists $self->$attr_reader->{$name} ? 1 : 0;
111 }) if exists $methods->{existence};
113 $META->add_method($methods->{remove} => sub {
114 my ($self, @values) = @_;
115 delete $self->$attr_reader->{$_} foreach @values;
116 }) if exists $methods->{remove};
119 ## some things don't always fit, so they go here ...
124 (defined $name && $name)
125 || Moose->throw_error("You must provide a name for the attribute");
127 if (scalar @_ == 1 && ref($_[0]) eq 'HASH') {
133 $self->get_attribute_map->{$name} = $attr_desc;
137 # sub _clean_up_required_methods {
139 # foreach my $method ($self->get_required_method_list) {
140 # $self->remove_required_methods($method)
141 # if $self->has_method($method);
145 ## ------------------------------------------------------------------
149 # the before/around/after method modifiers are
150 # stored by name, but there can be many methods
151 # then associated with that name. So again we have
152 # lots of similar functionality, so we can do some
153 # meta-programmin' and save some time.
156 foreach my $modifier_type (qw[ before around after ]) {
158 my $attr_reader = "get_${modifier_type}_method_modifiers_map";
160 # create the attribute ...
161 $META->add_attribute("${modifier_type}_method_modifiers" => (
162 reader => $attr_reader,
163 default => sub { {} }
166 # and some helper methods ...
167 $META->add_method("get_${modifier_type}_method_modifiers" => sub {
168 my ($self, $method_name) = @_;
169 #return () unless exists $self->$attr_reader->{$method_name};
170 @{$self->$attr_reader->{$method_name}};
173 $META->add_method("has_${modifier_type}_method_modifiers" => sub {
174 my ($self, $method_name) = @_;
176 # for now we assume that if it exists,..
177 # it has at least one modifier in it
178 (exists $self->$attr_reader->{$method_name}) ? 1 : 0;
181 $META->add_method("add_${modifier_type}_method_modifier" => sub {
182 my ($self, $method_name, $method) = @_;
184 $self->$attr_reader->{$method_name} = []
185 unless exists $self->$attr_reader->{$method_name};
187 my $modifiers = $self->$attr_reader->{$method_name};
190 # check to see that we aren't adding the
191 # same code twice. We err in favor of the
192 # first on here, this may not be as expected
193 foreach my $modifier (@{$modifiers}) {
194 return if $modifier == $method;
197 push @{$modifiers} => $method;
202 ## ------------------------------------------------------------------
203 ## override method mofidiers
205 $META->add_attribute('override_method_modifiers' => (
206 reader => 'get_override_method_modifiers_map',
207 default => sub { {} }
211 # these are a little different because there
212 # can only be one per name, whereas the other
213 # method modifiers can have multiples.
216 sub add_override_method_modifier {
217 my ($self, $method_name, $method) = @_;
218 (!$self->has_method($method_name))
219 || Moose->throw_error("Cannot add an override of method '$method_name' " .
220 "because there is a local version of '$method_name'");
221 $self->get_override_method_modifiers_map->{$method_name} = $method;
224 sub has_override_method_modifier {
225 my ($self, $method_name) = @_;
227 # for now we assume that if it exists,..
228 # it has at least one modifier in it
229 (exists $self->get_override_method_modifiers_map->{$method_name}) ? 1 : 0;
232 sub get_override_method_modifier {
233 my ($self, $method_name) = @_;
234 $self->get_override_method_modifiers_map->{$method_name};
237 ## general list accessor ...
239 sub get_method_modifier_list {
240 my ($self, $modifier_type) = @_;
241 my $accessor = "get_${modifier_type}_method_modifiers_map";
242 keys %{$self->$accessor};
245 sub reset_package_cache_flag { (shift)->{'_package_cache_flag'} = undef }
246 sub update_package_cache_flag {
248 $self->{'_package_cache_flag'} = Class::MOP::check_package_cache_flag($self->name);
253 ## ------------------------------------------------------------------
256 __PACKAGE__->meta->add_attribute('roles' => (
257 reader => 'get_roles',
258 default => sub { [] }
262 my ($self, $role) = @_;
263 (blessed($role) && $role->isa('Moose::Meta::Role'))
264 || Moose->throw_error("Roles must be instances of Moose::Meta::Role");
265 push @{$self->get_roles} => $role;
266 $self->reset_package_cache_flag;
269 sub calculate_all_roles {
275 $_->calculate_all_roles
276 } @{ $self->get_roles });
280 my ($self, $role_name) = @_;
282 || Moose->throw_error("You must supply a role name to look for");
283 # if we are it,.. then return true
284 return 1 if $role_name eq $self->name;
285 # otherwise.. check our children
286 foreach my $role (@{$self->get_roles}) {
287 return 1 if $role->does_role($role_name);
292 ## ------------------------------------------------------------------
295 sub method_metaclass { 'Moose::Meta::Role::Method' }
300 my $current = Class::MOP::check_package_cache_flag($self->name);
302 if (defined $self->{'_package_cache_flag'} && $self->{'_package_cache_flag'} == $current) {
303 return $self->{'methods'} ||= {};
306 $self->{_package_cache_flag} = $current;
308 my $map = $self->{'methods'} ||= {};
310 my $role_name = $self->name;
311 my $method_metaclass = $self->method_metaclass;
313 my %all_code = $self->get_all_package_symbols('CODE');
315 foreach my $symbol (keys %all_code) {
316 my $code = $all_code{$symbol};
318 next if exists $map->{$symbol} &&
319 defined $map->{$symbol} &&
320 $map->{$symbol}->body == $code;
322 my ($pkg, $name) = Class::MOP::get_code_info($code);
324 if ($pkg->can('meta')
326 # we don't know what ->meta we are calling
327 # here, so we need to be careful cause it
328 # just might blow up at us, or just complain
329 # loudly (in the case of Curses.pm) so we
330 # just be a little overly cautious here.
332 && eval { no warnings; blessed($pkg->meta) } # FIXME calls meta
333 && $pkg->meta->isa('Moose::Meta::Role')) {
334 my $role = $pkg->meta->name;
335 next unless $self->does_role($role);
339 # in 5.10 constant.pm the constants show up
340 # as being in the right package, but in pre-5.10
341 # they show up as constant::__ANON__ so we
342 # make an exception here to be sure that things
343 # work as expected in both.
345 unless ($pkg eq 'constant' && $name eq '__ANON__') {
346 next if ($pkg || '') ne $role_name ||
347 (($name || '') ne '__ANON__' && ($pkg || '') ne $role_name);
351 $map->{$symbol} = $method_metaclass->wrap(
353 package_name => $role_name,
362 my ($self, $name) = @_;
363 $self->get_method_map->{$name};
367 my ($self, $name) = @_;
368 exists $self->get_method_map->{$name} ? 1 : 0
371 # FIXME this is copypasated from Class::MOP::Class
372 # refactor to inherit from some common base
373 sub wrap_method_body {
374 my ( $self, %args ) = @_;
376 ('CODE' eq ref $args{body})
377 || Moose->throw_error("Your code block must be a CODE reference");
379 $self->method_metaclass->wrap(
380 package_name => $self->name,
386 my ($self, $method_name, $method) = @_;
387 (defined $method_name && $method_name)
388 || Moose->throw_error("You must define a method name");
391 if (blessed($method)) {
392 $body = $method->body;
393 if ($method->package_name ne $self->name) {
394 $method = $method->clone(
395 package_name => $self->name,
397 ) if $method->can('clone');
402 $method = $self->wrap_method_body( body => $body, name => $method_name );
405 $method->attach_to_class($self);
407 $self->get_method_map->{$method_name} = $method;
409 my $full_method_name = ($self->name . '::' . $method_name);
410 $self->add_package_symbol(
411 { sigil => '&', type => 'CODE', name => $method_name },
412 Class::MOP::subname($full_method_name => $body)
415 $self->update_package_cache_flag; # still valid, since we just added the method to the map, and if it was invalid before that then get_method_map updated it
418 sub find_method_by_name { (shift)->get_method(@_) }
420 sub get_method_list {
422 grep { !/^meta$/ } keys %{$self->get_method_map};
428 $self->add_method(@_);
431 ## ------------------------------------------------------------------
433 ## ------------------------------------------------------------------
436 my ($self, $other, @args) = @_;
439 || Moose->throw_error("You must pass in an blessed instance");
441 if ($other->isa('Moose::Meta::Role')) {
442 require Moose::Meta::Role::Application::ToRole;
443 return Moose::Meta::Role::Application::ToRole->new(@args)->apply($self, $other);
445 elsif ($other->isa('Moose::Meta::Class')) {
446 require Moose::Meta::Role::Application::ToClass;
447 return Moose::Meta::Role::Application::ToClass->new(@args)->apply($self, $other);
450 require Moose::Meta::Role::Application::ToInstance;
451 return Moose::Meta::Role::Application::ToInstance->new(@args)->apply($self, $other);
456 my ($class, @role_specs) = @_;
458 require Moose::Meta::Role::Application::RoleSummation;
459 require Moose::Meta::Role::Composite;
461 my (@roles, %role_params);
462 while (@role_specs) {
463 my ($role, $params) = @{ splice @role_specs, 0, 1 };
464 push @roles => $role->meta;
465 next unless defined $params;
466 $role_params{$role} = $params;
469 my $c = Moose::Meta::Role::Composite->new(roles => \@roles);
470 Moose::Meta::Role::Application::RoleSummation->new(
471 role_params => \%role_params
477 #####################################################################
479 ## This is Moose::Meta::Role as defined by Moose (plus the use of
480 ## MooseX::AttributeHelpers module). It is here as a reference to
481 ## make it easier to see what is happening above with all the meta
483 #####################################################################
486 # metaclass => 'Collection::Array',
487 # reader => 'get_roles',
488 # isa => 'ArrayRef[Moose::Meta::Roles]',
489 # default => sub { [] },
491 # 'push' => 'add_role',
495 # has 'excluded_roles_map' => (
496 # metaclass => 'Collection::Hash',
497 # reader => 'get_excluded_roles_map',
498 # isa => 'HashRef[Str]',
500 # # Not exactly set, cause it sets multiple
501 # 'set' => 'add_excluded_roles',
502 # 'keys' => 'get_excluded_roles_list',
503 # 'exists' => 'excludes_role',
507 # has 'attribute_map' => (
508 # metaclass => 'Collection::Hash',
509 # reader => 'get_attribute_map',
510 # isa => 'HashRef[Str]',
512 # # 'set' => 'add_attribute' # has some special crap in it
513 # 'get' => 'get_attribute',
514 # 'keys' => 'get_attribute_list',
515 # 'exists' => 'has_attribute',
516 # # Not exactly delete, cause it sets multiple
517 # 'delete' => 'remove_attribute',
521 # has 'required_methods' => (
522 # metaclass => 'Collection::Hash',
523 # reader => 'get_required_methods_map',
524 # isa => 'HashRef[Str]',
526 # # not exactly set, or delete since it works for multiple
527 # 'set' => 'add_required_methods',
528 # 'delete' => 'remove_required_methods',
529 # 'keys' => 'get_required_method_list',
530 # 'exists' => 'requires_method',
534 # # the before, around and after modifiers are
535 # # HASH keyed by method-name, with ARRAY of
536 # # CODE refs to apply in that order
538 # has 'before_method_modifiers' => (
539 # metaclass => 'Collection::Hash',
540 # reader => 'get_before_method_modifiers_map',
541 # isa => 'HashRef[ArrayRef[CodeRef]]',
543 # 'keys' => 'get_before_method_modifiers',
544 # 'exists' => 'has_before_method_modifiers',
545 # # This actually makes sure there is an
546 # # ARRAY at the given key, and pushed onto
547 # # it. It also checks for duplicates as well
548 # # 'add' => 'add_before_method_modifier'
552 # has 'after_method_modifiers' => (
553 # metaclass => 'Collection::Hash',
554 # reader =>'get_after_method_modifiers_map',
555 # isa => 'HashRef[ArrayRef[CodeRef]]',
557 # 'keys' => 'get_after_method_modifiers',
558 # 'exists' => 'has_after_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_after_method_modifier'
566 # has 'around_method_modifiers' => (
567 # metaclass => 'Collection::Hash',
568 # reader =>'get_around_method_modifiers_map',
569 # isa => 'HashRef[ArrayRef[CodeRef]]',
571 # 'keys' => 'get_around_method_modifiers',
572 # 'exists' => 'has_around_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_around_method_modifier'
580 # # override is similar to the other modifiers
581 # # except that it is not an ARRAY of code refs
582 # # but instead just a single name->code mapping
584 # has 'override_method_modifiers' => (
585 # metaclass => 'Collection::Hash',
586 # reader =>'get_override_method_modifiers_map',
587 # isa => 'HashRef[CodeRef]',
589 # 'keys' => 'get_override_method_modifier',
590 # 'exists' => 'has_override_method_modifier',
591 # 'add' => 'add_override_method_modifier', # checks for local method ..
595 #####################################################################
606 Moose::Meta::Role - The Moose Role metaclass
610 Please see L<Moose::Role> for more information about roles.
611 For the most part, this has no user-serviceable parts inside
612 this module. It's API is still subject to some change (although
613 probably not that much really).
625 =item B<apply_to_metaclass_instance>
653 =item B<add_excluded_roles>
655 =item B<excludes_role>
657 =item B<get_excluded_roles_list>
659 =item B<get_excluded_roles_map>
661 =item B<calculate_all_roles>
667 =item B<method_metaclass>
669 =item B<find_method_by_name>
677 =item B<wrap_method_body>
679 =item B<alias_method>
681 =item B<get_method_list>
683 =item B<get_method_map>
685 =item B<update_package_cache_flag>
687 =item B<reset_package_cache_flag>
693 =item B<add_attribute>
695 =item B<has_attribute>
697 =item B<get_attribute>
699 =item B<get_attribute_list>
701 =item B<get_attribute_map>
703 =item B<remove_attribute>
709 =item B<add_required_methods>
711 =item B<remove_required_methods>
713 =item B<get_required_method_list>
715 =item B<get_required_methods_map>
717 =item B<requires_method>
723 =item B<add_after_method_modifier>
725 =item B<add_around_method_modifier>
727 =item B<add_before_method_modifier>
729 =item B<add_override_method_modifier>
735 =item B<has_after_method_modifiers>
737 =item B<has_around_method_modifiers>
739 =item B<has_before_method_modifiers>
741 =item B<has_override_method_modifier>
747 =item B<get_after_method_modifiers>
749 =item B<get_around_method_modifiers>
751 =item B<get_before_method_modifiers>
753 =item B<get_method_modifier_list>
759 =item B<get_override_method_modifier>
761 =item B<get_after_method_modifiers_map>
763 =item B<get_around_method_modifiers_map>
765 =item B<get_before_method_modifiers_map>
767 =item B<get_override_method_modifiers_map>
773 All complex software has bugs lurking in it, and this module is no
774 exception. If you find a bug please either email me, or add the bug
779 Stevan Little E<lt>stevan@iinteractive.comE<gt>
781 =head1 COPYRIGHT AND LICENSE
783 Copyright 2006-2008 by Infinity Interactive, Inc.
785 L<http://www.iinteractive.com>
787 This library is free software; you can redistribute it and/or modify
788 it under the same terms as Perl itself.