deprecate get_attribute_map for roles, and remove it from the recipes
[gitmo/Moose.git] / lib / Moose / Meta / Role.pm
CommitLineData
e185c027 1
2package Moose::Meta::Role;
3
4use strict;
5use warnings;
6use metaclass;
7
21f1e231 8use Scalar::Util 'blessed';
b6a00b82 9use Carp 'confess';
963c24e1 10use Devel::GlobalDestruction 'in_global_destruction';
bdabd620 11
8de57178 12our $VERSION = '0.92';
e606ae5f 13$VERSION = eval $VERSION;
d44714be 14our $AUTHORITY = 'cpan:STEVAN';
e185c027 15
8ee73eeb 16use Moose::Meta::Class;
39b3bc94 17use Moose::Meta::Role::Method;
d67145ed 18use Moose::Meta::Role::Method::Required;
bb153262 19use Moose::Meta::Role::Method::Conflicting;
8ee73eeb 20
68efb014 21use base 'Class::MOP::Module';
80572233 22
fb1e11d5 23## ------------------------------------------------------------------
24## NOTE:
25## I normally don't do this, but I am doing
26## a whole bunch of meta-programmin in this
27## module, so it just makes sense. For a clearer
d03bd989 28## picture of what is going on in the next
29## several lines of code, look at the really
fb1e11d5 30## big comment at the end of this file (right
31## before the POD).
32## - SL
33## ------------------------------------------------------------------
80572233 34
21716c07 35my $META = __PACKAGE__->meta;
36
37## ------------------------------------------------------------------
38## attributes ...
e185c027 39
21716c07 40# NOTE:
41# since roles are lazy, we hold all the attributes
fb1e11d5 42# of the individual role in 'statis' until which
43# time when it is applied to a class. This means
44# keeping a lot of things in hash maps, so we are
21716c07 45# using a little of that meta-programmin' magic
d03bd989 46# here an saving lots of extra typin. And since
fb1e11d5 47# many of these attributes above require similar
48# functionality to support them, so we again use
49# the wonders of meta-programmin' to deliver a
21716c07 50# very compact solution to this normally verbose
51# problem.
52# - SL
53
54foreach my $action (
fb1e11d5 55 {
56 name => 'excluded_roles_map',
57 attr_reader => 'get_excluded_roles_map' ,
21716c07 58 methods => {
fb1e11d5 59 add => 'add_excluded_roles',
55f28f0a 60 get_keys => 'get_excluded_roles_list',
fb1e11d5 61 existence => 'excludes_role',
21716c07 62 }
63 },
fb1e11d5 64 {
65 name => 'required_methods',
21716c07 66 attr_reader => 'get_required_methods_map',
67 methods => {
7c62cb0a 68 remove => 'remove_required_methods',
69 get_values => 'get_required_method_list',
70 existence => 'requires_method',
21716c07 71 }
d03bd989 72 },
21716c07 73 {
ce444596 74 name => '_attribute_map',
75 attr_reader => '_attribute_map',
21716c07 76 methods => {
77 get => 'get_attribute',
55f28f0a 78 get_keys => 'get_attribute_list',
21716c07 79 existence => 'has_attribute',
80 remove => 'remove_attribute',
81 }
82 }
83) {
fb1e11d5 84
21716c07 85 my $attr_reader = $action->{attr_reader};
86 my $methods = $action->{methods};
fb1e11d5 87
88 # create the attribute
89 $META->add_attribute($action->{name} => (
90 reader => $attr_reader,
91 default => sub { {} }
92 ));
93
94 # create some helper methods
21716c07 95 $META->add_method($methods->{add} => sub {
96 my ($self, @values) = @_;
fb1e11d5 97 $self->$attr_reader->{$_} = undef foreach @values;
21716c07 98 }) if exists $methods->{add};
fb1e11d5 99
55f28f0a 100 $META->add_method($methods->{get_keys} => sub {
21716c07 101 my ($self) = @_;
fb1e11d5 102 keys %{$self->$attr_reader};
55f28f0a 103 }) if exists $methods->{get_keys};
fb1e11d5 104
8a0bfed9 105 $META->add_method($methods->{get_values} => sub {
106 my ($self) = @_;
107 values %{$self->$attr_reader};
108 }) if exists $methods->{get_values};
109
21716c07 110 $META->add_method($methods->{get} => sub {
111 my ($self, $name) = @_;
fb1e11d5 112 $self->$attr_reader->{$name}
113 }) if exists $methods->{get};
114
21716c07 115 $META->add_method($methods->{existence} => sub {
116 my ($self, $name) = @_;
fb1e11d5 117 exists $self->$attr_reader->{$name} ? 1 : 0;
118 }) if exists $methods->{existence};
119
21716c07 120 $META->add_method($methods->{remove} => sub {
121 my ($self, @values) = @_;
122 delete $self->$attr_reader->{$_} foreach @values;
fb1e11d5 123 }) if exists $methods->{remove};
21716c07 124}
d79e62fd 125
b05518b2 126$META->add_attribute(
127 'method_metaclass',
128 reader => 'method_metaclass',
129 default => 'Moose::Meta::Role::Method',
130);
131
77ed8b8d 132$META->add_attribute(
133 'required_method_metaclass',
134 reader => 'required_method_metaclass',
135 default => 'Moose::Meta::Role::Method::Required',
136);
137
eec8ca8a 138$META->add_attribute(
bb153262 139 'conflicting_method_metaclass',
140 reader => 'conflicting_method_metaclass',
141 default => 'Moose::Meta::Role::Method::Conflicting',
eec8ca8a 142);
143
07de7559 144$META->add_attribute(
145 'application_to_class_class',
146 reader => 'application_to_class_class',
147 default => 'Moose::Meta::Role::Application::ToClass',
148);
149
150$META->add_attribute(
151 'application_to_role_class',
152 reader => 'application_to_role_class',
153 default => 'Moose::Meta::Role::Application::ToRole',
154);
155
156$META->add_attribute(
157 'application_to_instance_class',
158 reader => 'application_to_instance_class',
159 default => 'Moose::Meta::Role::Application::ToInstance',
160);
161
12d8c847 162$META->add_attribute(
163 'composition_class_roles',
164 reader => 'composition_class_roles',
165 predicate => 'has_composition_class_roles',
166);
167
21716c07 168## some things don't always fit, so they go here ...
80572233 169
21716c07 170sub add_attribute {
171 my $self = shift;
172 my $name = shift;
52ac1d4a 173 unless ( defined $name ) {
70ea9161 174 require Moose;
175 Moose->throw_error("You must provide a name for the attribute");
176 }
21716c07 177 my $attr_desc;
178 if (scalar @_ == 1 && ref($_[0]) eq 'HASH') {
179 $attr_desc = $_[0];
180 }
181 else {
182 $attr_desc = { @_ };
183 }
ce444596 184 $self->_attribute_map->{$name} = $attr_desc;
21716c07 185}
e185c027 186
16d721b3 187sub add_required_methods {
188 my $self = shift;
189
190 for (@_) {
191 my $method = $_;
c9d7e396 192 if (!blessed($method)) {
16d721b3 193 $method = $self->required_method_metaclass->new(
194 name => $method,
195 );
196 }
197 $self->get_required_methods_map->{$method->name} = $method;
198 }
199}
200
bb153262 201sub add_conflicting_method {
09eeab06 202 my $self = shift;
203
204 my $method;
205 if (@_ == 1 && blessed($_[0])) {
206 $method = shift;
207 }
208 else {
bb153262 209 $method = $self->conflicting_method_metaclass->new(@_);
09eeab06 210 }
211
212 $self->add_required_methods($method);
213}
214
21716c07 215## ------------------------------------------------------------------
216## method modifiers
217
21716c07 218# NOTE:
fb1e11d5 219# the before/around/after method modifiers are
21716c07 220# stored by name, but there can be many methods
221# then associated with that name. So again we have
222# lots of similar functionality, so we can do some
223# meta-programmin' and save some time.
224# - SL
225
226foreach my $modifier_type (qw[ before around after ]) {
fb1e11d5 227
228 my $attr_reader = "get_${modifier_type}_method_modifiers_map";
d03bd989 229
fb1e11d5 230 # create the attribute ...
231 $META->add_attribute("${modifier_type}_method_modifiers" => (
232 reader => $attr_reader,
233 default => sub { {} }
d03bd989 234 ));
fb1e11d5 235
236 # and some helper methods ...
21716c07 237 $META->add_method("get_${modifier_type}_method_modifiers" => sub {
238 my ($self, $method_name) = @_;
fb1e11d5 239 #return () unless exists $self->$attr_reader->{$method_name};
d9847263 240 my $mm = $self->$attr_reader->{$method_name};
241 $mm ? @$mm : ();
21716c07 242 });
fb1e11d5 243
21716c07 244 $META->add_method("has_${modifier_type}_method_modifiers" => sub {
245 my ($self, $method_name) = @_;
246 # NOTE:
fb1e11d5 247 # for now we assume that if it exists,..
21716c07 248 # it has at least one modifier in it
249 (exists $self->$attr_reader->{$method_name}) ? 1 : 0;
fb1e11d5 250 });
251
21716c07 252 $META->add_method("add_${modifier_type}_method_modifier" => sub {
253 my ($self, $method_name, $method) = @_;
fb1e11d5 254
255 $self->$attr_reader->{$method_name} = []
21716c07 256 unless exists $self->$attr_reader->{$method_name};
fb1e11d5 257
21716c07 258 my $modifiers = $self->$attr_reader->{$method_name};
fb1e11d5 259
21716c07 260 # NOTE:
fb1e11d5 261 # check to see that we aren't adding the
262 # same code twice. We err in favor of the
21716c07 263 # first on here, this may not be as expected
264 foreach my $modifier (@{$modifiers}) {
265 return if $modifier == $method;
266 }
fb1e11d5 267
21716c07 268 push @{$modifiers} => $method;
269 });
fb1e11d5 270
21716c07 271}
1331430a 272
21716c07 273## ------------------------------------------------------------------
274## override method mofidiers
0558683c 275
fb1e11d5 276$META->add_attribute('override_method_modifiers' => (
277 reader => 'get_override_method_modifiers_map',
278 default => sub { {} }
279));
280
21716c07 281# NOTE:
fb1e11d5 282# these are a little different because there
21716c07 283# can only be one per name, whereas the other
284# method modifiers can have multiples.
285# - SL
0558683c 286
21716c07 287sub add_override_method_modifier {
288 my ($self, $method_name, $method) = @_;
289 (!$self->has_method($method_name))
c245d69b 290 || Moose->throw_error("Cannot add an override of method '$method_name' " .
4c0b3599 291 "because there is a local version of '$method_name'");
fb1e11d5 292 $self->get_override_method_modifiers_map->{$method_name} = $method;
21716c07 293}
0558683c 294
21716c07 295sub has_override_method_modifier {
296 my ($self, $method_name) = @_;
297 # NOTE:
fb1e11d5 298 # for now we assume that if it exists,..
21716c07 299 # it has at least one modifier in it
fb1e11d5 300 (exists $self->get_override_method_modifiers_map->{$method_name}) ? 1 : 0;
21716c07 301}
0558683c 302
21716c07 303sub get_override_method_modifier {
304 my ($self, $method_name) = @_;
fb1e11d5 305 $self->get_override_method_modifiers_map->{$method_name};
21716c07 306}
0558683c 307
21716c07 308## general list accessor ...
80572233 309
21716c07 310sub get_method_modifier_list {
311 my ($self, $modifier_type) = @_;
fb1e11d5 312 my $accessor = "get_${modifier_type}_method_modifiers_map";
21716c07 313 keys %{$self->$accessor};
314}
e185c027 315
e606ae5f 316sub reset_package_cache_flag { (shift)->{'_package_cache_flag'} = undef }
317sub update_package_cache_flag {
318 my $self = shift;
319 $self->{'_package_cache_flag'} = Class::MOP::check_package_cache_flag($self->name);
320}
321
322
323
21716c07 324## ------------------------------------------------------------------
80572233 325## subroles
326
278ca49c 327$META->add_attribute('roles' => (
21716c07 328 reader => 'get_roles',
329 default => sub { [] }
330));
331
80572233 332sub add_role {
333 my ($self, $role) = @_;
334 (blessed($role) && $role->isa('Moose::Meta::Role'))
c245d69b 335 || Moose->throw_error("Roles must be instances of Moose::Meta::Role");
80572233 336 push @{$self->get_roles} => $role;
e606ae5f 337 $self->reset_package_cache_flag;
80572233 338}
339
b8aeb4dc 340sub calculate_all_roles {
341 my $self = shift;
342 my %seen;
fb1e11d5 343 grep {
344 !$seen{$_->name}++
345 } ($self, map {
346 $_->calculate_all_roles
347 } @{ $self->get_roles });
b8aeb4dc 348}
349
80572233 350sub does_role {
351 my ($self, $role_name) = @_;
352 (defined $role_name)
c245d69b 353 || Moose->throw_error("You must supply a role name to look for");
bdabd620 354 # if we are it,.. then return true
355 return 1 if $role_name eq $self->name;
356 # otherwise.. check our children
80572233 357 foreach my $role (@{$self->get_roles}) {
bdabd620 358 return 1 if $role->does_role($role_name);
80572233 359 }
360 return 0;
361}
362
1db8ecc7 363sub find_method_by_name { (shift)->get_method(@_) }
093b12c2 364
fb1e11d5 365sub alias_method {
8b7cb9ab 366 Carp::cluck("The alias_method method is deprecated. Use add_method instead.\n");
89e6757a 367
87e63626 368 my $self = shift;
fb1e11d5 369
87e63626 370 $self->add_method(@_);
fb1e11d5 371}
372
21716c07 373## ------------------------------------------------------------------
fb1e11d5 374## role construction
21716c07 375## ------------------------------------------------------------------
e185c027 376
21716c07 377sub apply {
bca01282 378 my ($self, $other, @args) = @_;
379
380 (blessed($other))
c245d69b 381 || Moose->throw_error("You must pass in an blessed instance");
d03bd989 382
07de7559 383 my $application_class;
1c9db35c 384 if ($other->isa('Moose::Meta::Role')) {
07de7559 385 $application_class = $self->application_to_role_class;
1c9db35c 386 }
387 elsif ($other->isa('Moose::Meta::Class')) {
07de7559 388 $application_class = $self->application_to_class_class;
d03bd989 389 }
1c9db35c 390 else {
07de7559 391 $application_class = $self->application_to_instance_class;
d03bd989 392 }
07de7559 393
394 Class::MOP::load_class($application_class);
395 return $application_class->new(@args)->apply($self, $other);
0558683c 396}
397
21716c07 398sub combine {
a4e516f6 399 my ($class, @role_specs) = @_;
d03bd989 400
d03bd989 401 require Moose::Meta::Role::Composite;
402
28412c0b 403 my (@roles, %role_params);
404 while (@role_specs) {
31d96c3e 405 my ($role_name, $params) = @{ splice @role_specs, 0, 1 };
406 my $requested_role = Class::MOP::class_of($role_name);
407
6bdef412 408 my $actual_role = $requested_role->_role_for_combination($params);
31d96c3e 409 push @roles => $actual_role;
410
28412c0b 411 next unless defined $params;
31d96c3e 412 $role_params{$actual_role->name} = $params;
28412c0b 413 }
d03bd989 414
fb1e11d5 415 my $c = Moose::Meta::Role::Composite->new(roles => \@roles);
7071e2cb 416 return $c->apply_params(\%role_params);
0558683c 417}
418
6bdef412 419sub _role_for_combination {
436d7a28 420 my ($self, $params) = @_;
421 return $self;
422}
423
b6a00b82 424sub create {
2d5f3fab 425 my ( $role, $package_name, %options ) = @_;
b6a00b82 426
2d5f3fab 427 $options{package} = $package_name;
b6a00b82 428
429 (ref $options{attributes} eq 'HASH')
430 || confess "You must pass a HASH ref of attributes"
431 if exists $options{attributes};
432
433 (ref $options{methods} eq 'HASH')
434 || confess "You must pass a HASH ref of methods"
435 if exists $options{methods};
436
2d5f3fab 437 my (%initialize_options) = %options;
b6a00b82 438 delete @initialize_options{qw(
439 package
440 attributes
441 methods
442 version
443 authority
444 )};
445
446 my $meta = $role->initialize( $package_name => %initialize_options );
447
6a4a7c31 448 $meta->_instantiate_module( $options{version}, $options{authority} );
449
b6a00b82 450 # FIXME totally lame
451 $meta->add_method('meta' => sub {
452 $role->initialize(ref($_[0]) || $_[0]);
453 });
454
455 if (exists $options{attributes}) {
456 foreach my $attribute_name (keys %{$options{attributes}}) {
457 my $attr = $options{attributes}->{$attribute_name};
458 $meta->add_attribute($attribute_name => $attr);
459 }
460 }
461
462 if (exists $options{methods}) {
463 foreach my $method_name (keys %{$options{methods}}) {
464 $meta->add_method($method_name, $options{methods}->{$method_name});
465 }
466 }
467
d1765290 468 Class::MOP::weaken_metaclass($meta->name)
469 if $meta->is_anon_role;
470
b6a00b82 471 return $meta;
472}
473
c9ee520d 474# anonymous roles. most of it is copied straight out of Class::MOP::Class.
475# an intrepid hacker might find great riches if he unifies this code with that
476# code in Class::MOP::Module or Class::MOP::Package
477{
478 # NOTE:
479 # this should be sufficient, if you have a
480 # use case where it is not, write a test and
481 # I will change it.
482 my $ANON_ROLE_SERIAL = 0;
483
484 # NOTE:
485 # we need a sufficiently annoying prefix
486 # this should suffice for now, this is
487 # used in a couple of places below, so
488 # need to put it up here for now.
489 my $ANON_ROLE_PREFIX = 'Moose::Meta::Role::__ANON__::SERIAL::';
490
491 sub is_anon_role {
492 my $self = shift;
493 no warnings 'uninitialized';
494 $self->name =~ /^$ANON_ROLE_PREFIX/;
495 }
496
497 sub create_anon_role {
498 my ($role, %options) = @_;
499 my $package_name = $ANON_ROLE_PREFIX . ++$ANON_ROLE_SERIAL;
500 return $role->create($package_name, %options);
501 }
502
503 # NOTE:
504 # this will only get called for
505 # anon-roles, all other calls
506 # are assumed to occur during
507 # global destruction and so don't
508 # really need to be handled explicitly
509 sub DESTROY {
510 my $self = shift;
511
963c24e1 512 return if in_global_destruction(); # it'll happen soon anyway and this just makes things more complicated
c9ee520d 513
514 no warnings 'uninitialized';
515 return unless $self->name =~ /^$ANON_ROLE_PREFIX/;
516
517 # XXX: is this necessary for us? I don't understand what it's doing
518 # -sartak
519
520 # Moose does a weird thing where it replaces the metaclass for
521 # class when fixing metaclass incompatibility. In that case,
522 # we don't want to clean out the namespace now. We can detect
523 # that because Moose will explicitly update the singleton
524 # cache in Class::MOP.
525 #my $current_meta = Class::MOP::get_metaclass_by_name($self->name);
526 #return if $current_meta ne $self;
527
528 my ($serial_id) = ($self->name =~ /^$ANON_ROLE_PREFIX(\d+)/);
529 no strict 'refs';
530 foreach my $key (keys %{$ANON_ROLE_PREFIX . $serial_id}) {
531 delete ${$ANON_ROLE_PREFIX . $serial_id}{$key};
532 }
533 delete ${'main::' . $ANON_ROLE_PREFIX}{$serial_id . '::'};
534 }
535}
536
fb1e11d5 537#####################################################################
538## NOTE:
d03bd989 539## This is Moose::Meta::Role as defined by Moose (plus the use of
540## MooseX::AttributeHelpers module). It is here as a reference to
fb1e11d5 541## make it easier to see what is happening above with all the meta
542## programming. - SL
543#####################################################################
544#
545# has 'roles' => (
a40b446a 546# metaclass => 'Array',
fb1e11d5 547# reader => 'get_roles',
764a7831 548# isa => 'ArrayRef[Moose::Meta::Role]',
fb1e11d5 549# default => sub { [] },
550# provides => {
551# 'push' => 'add_role',
552# }
553# );
d03bd989 554#
fb1e11d5 555# has 'excluded_roles_map' => (
a40b446a 556# metaclass => 'Hash',
fb1e11d5 557# reader => 'get_excluded_roles_map',
558# isa => 'HashRef[Str]',
559# provides => {
560# # Not exactly set, cause it sets multiple
561# 'set' => 'add_excluded_roles',
562# 'keys' => 'get_excluded_roles_list',
563# 'exists' => 'excludes_role',
564# }
565# );
d03bd989 566#
fb1e11d5 567# has 'attribute_map' => (
a40b446a 568# metaclass => 'Hash',
ce444596 569# reader => '_attribute_map',
d03bd989 570# isa => 'HashRef[Str]',
fb1e11d5 571# provides => {
572# # 'set' => 'add_attribute' # has some special crap in it
573# 'get' => 'get_attribute',
574# 'keys' => 'get_attribute_list',
575# 'exists' => 'has_attribute',
576# # Not exactly delete, cause it sets multiple
d03bd989 577# 'delete' => 'remove_attribute',
fb1e11d5 578# }
579# );
d03bd989 580#
fb1e11d5 581# has 'required_methods' => (
a40b446a 582# metaclass => 'Hash',
fb1e11d5 583# reader => 'get_required_methods_map',
72264f10 584# isa => 'HashRef[Moose::Meta::Role::Method::Required]',
d03bd989 585# provides => {
586# # not exactly set, or delete since it works for multiple
fb1e11d5 587# 'set' => 'add_required_methods',
588# 'delete' => 'remove_required_methods',
589# 'keys' => 'get_required_method_list',
d03bd989 590# 'exists' => 'requires_method',
fb1e11d5 591# }
592# );
d03bd989 593#
594# # the before, around and after modifiers are
595# # HASH keyed by method-name, with ARRAY of
fb1e11d5 596# # CODE refs to apply in that order
d03bd989 597#
fb1e11d5 598# has 'before_method_modifiers' => (
a40b446a 599# metaclass => 'Hash',
fb1e11d5 600# reader => 'get_before_method_modifiers_map',
601# isa => 'HashRef[ArrayRef[CodeRef]]',
602# provides => {
603# 'keys' => 'get_before_method_modifiers',
d03bd989 604# 'exists' => 'has_before_method_modifiers',
605# # This actually makes sure there is an
fb1e11d5 606# # ARRAY at the given key, and pushed onto
607# # it. It also checks for duplicates as well
d03bd989 608# # 'add' => 'add_before_method_modifier'
609# }
fb1e11d5 610# );
d03bd989 611#
fb1e11d5 612# has 'after_method_modifiers' => (
a40b446a 613# metaclass => 'Hash',
fb1e11d5 614# reader =>'get_after_method_modifiers_map',
615# isa => 'HashRef[ArrayRef[CodeRef]]',
616# provides => {
617# 'keys' => 'get_after_method_modifiers',
d03bd989 618# 'exists' => 'has_after_method_modifiers',
619# # This actually makes sure there is an
fb1e11d5 620# # ARRAY at the given key, and pushed onto
d03bd989 621# # it. It also checks for duplicates as well
622# # 'add' => 'add_after_method_modifier'
623# }
fb1e11d5 624# );
d03bd989 625#
fb1e11d5 626# has 'around_method_modifiers' => (
a40b446a 627# metaclass => 'Hash',
fb1e11d5 628# reader =>'get_around_method_modifiers_map',
629# isa => 'HashRef[ArrayRef[CodeRef]]',
630# provides => {
631# 'keys' => 'get_around_method_modifiers',
d03bd989 632# 'exists' => 'has_around_method_modifiers',
633# # This actually makes sure there is an
fb1e11d5 634# # ARRAY at the given key, and pushed onto
d03bd989 635# # it. It also checks for duplicates as well
636# # 'add' => 'add_around_method_modifier'
637# }
fb1e11d5 638# );
d03bd989 639#
fb1e11d5 640# # override is similar to the other modifiers
641# # except that it is not an ARRAY of code refs
642# # but instead just a single name->code mapping
d03bd989 643#
fb1e11d5 644# has 'override_method_modifiers' => (
a40b446a 645# metaclass => 'Hash',
fb1e11d5 646# reader =>'get_override_method_modifiers_map',
d03bd989 647# isa => 'HashRef[CodeRef]',
fb1e11d5 648# provides => {
649# 'keys' => 'get_override_method_modifier',
d03bd989 650# 'exists' => 'has_override_method_modifier',
651# 'add' => 'add_override_method_modifier', # checks for local method ..
fb1e11d5 652# }
653# );
d03bd989 654#
fb1e11d5 655#####################################################################
656
657
e185c027 6581;
659
660__END__
661
662=pod
663
664=head1 NAME
665
666Moose::Meta::Role - The Moose Role metaclass
667
668=head1 DESCRIPTION
669
705d4cfd 670This class is a subclass of L<Class::MOP::Module> that provides
671additional Moose-specific functionality.
672
673It's API looks a lot like L<Moose::Meta::Class>, but internally it
674implements many things differently. This may change in the future.
79592a54 675
cf3bb5c5 676=head1 INHERITANCE
677
678C<Moose::Meta::Role> is a subclass of L<Class::MOP::Module>.
679
e185c027 680=head1 METHODS
681
705d4cfd 682=head2 Construction
683
e185c027 684=over 4
685
705d4cfd 686=item B<< Moose::Meta::Role->initialize($role_name) >>
e185c027 687
705d4cfd 688This method creates a new role object with the provided name.
e185c027 689
705d4cfd 690=item B<< Moose::Meta::Role->combine( [ $role => { ... } ], [ $role ], ... ) >>
78cd1d3b 691
705d4cfd 692This method accepts a list of array references. Each array reference
693should contain a role name as its first element. The second element is
c8b8d92f 694an optional hash reference. The hash reference can contain C<-excludes>
695and C<-alias> keys to control how methods are composed from the role.
e606ae5f 696
705d4cfd 697The return value is a new L<Moose::Meta::Role::Composite> that
698represents the combined roles.
db1ab48d 699
705d4cfd 700=item B<< Moose::Meta::Role->create($name, %options) >>
e185c027 701
705d4cfd 702This method is identical to the L<Moose::Meta::Class> C<create>
703method.
704
705=item B<< Moose::Meta::Role->create_anon_role >>
e185c027 706
705d4cfd 707This method is identical to the L<Moose::Meta::Class>
708C<create_anon_class> method.
e185c027 709
705d4cfd 710=item B<< $metarole->is_anon_role >>
e185c027 711
705d4cfd 712Returns true if the role is an anonymous role.
e185c027 713
714=back
715
705d4cfd 716=head2 Role application
717
e185c027 718=over 4
719
705d4cfd 720=item B<< $metarole->apply( $thing, @options ) >>
80572233 721
705d4cfd 722This method applies a role to the given C<$thing>. That can be another
723L<Moose::Meta::Role>, object, a L<Moose::Meta::Class> object, or a
724(non-meta) object instance.
80572233 725
705d4cfd 726The options are passed directly to the constructor for the appropriate
727L<Moose::Meta::Role::Application> subclass.
80572233 728
d05235e1 729Note that this will apply the role even if the C<$thing> in question already
730C<does> this role. L<Moose::Util/does_role> is a convenient wrapper for
731finding out if role application is necessary.
732
80572233 733=back
734
705d4cfd 735=head2 Roles and other roles
736
80572233 737=over 4
738
705d4cfd 739=item B<< $metarole->get_roles >>
d79e62fd 740
705d4cfd 741This returns an array reference of roles which this role does. This
742list may include duplicates.
d79e62fd 743
705d4cfd 744=item B<< $metarole->calculate_all_roles >>
d79e62fd 745
705d4cfd 746This returns a I<unique> list of all roles that this role does, and
747all the roles that its roles do.
d79e62fd 748
705d4cfd 749=item B<< $metarole->does_role($role_name) >>
2b14ac61 750
705d4cfd 751Given a role I<name>, returns true if this role does the given
752role.
d79e62fd 753
705d4cfd 754=item B<< $metarole->add_role($role) >>
d79e62fd 755
705d4cfd 756Given a L<Moose::Meta::Role> object, this adds the role to the list of
757roles that the role does.
68efb014 758
705d4cfd 759=item B<< $metarole->get_excluded_roles_list >>
be4427d0 760
705d4cfd 761Returns a list of role names which this role excludes.
e185c027 762
705d4cfd 763=item B<< $metarole->excludes_role($role_name) >>
e185c027 764
705d4cfd 765Given a role I<name>, returns true if this role excludes the named
766role.
e606ae5f 767
705d4cfd 768=item B<< $metarole->add_excluded_roles(@role_names) >>
e606ae5f 769
705d4cfd 770Given one or more role names, adds those roles to the list of excluded
771roles.
bdabd620 772
705d4cfd 773=back
e185c027 774
705d4cfd 775=head2 Methods
093b12c2 776
705d4cfd 777The methods for dealing with a role's methods are all identical in API
778and behavior to the same methods in L<Class::MOP::Class>.
638853cb 779
705d4cfd 780=over 4
53dd42d8 781
705d4cfd 782=item B<< $metarole->method_metaclass >>
e185c027 783
705d4cfd 784Returns the method metaclass name for the role. This defaults to
785L<Moose::Meta::Role::Method>.
e185c027 786
705d4cfd 787=item B<< $metarole->get_method($name) >>
e185c027 788
705d4cfd 789=item B<< $metarole->has_method($name) >>
e185c027 790
705d4cfd 791=item B<< $metarole->add_method( $name, $body ) >>
e185c027 792
705d4cfd 793=item B<< $metarole->get_method_list >>
e185c027 794
705d4cfd 795=item B<< $metarole->find_method_by_name($name) >>
796
797These methods are all identical to the methods of the same name in
8f6cbfcd 798L<Class::MOP::Package>
e185c027 799
800=back
801
705d4cfd 802=head2 Attributes
803
804As with methods, the methods for dealing with a role's attribute are
805all identical in API and behavior to the same methods in
806L<Class::MOP::Class>.
807
808However, attributes stored in this class are I<not> stored as
809objects. Rather, the attribute definition is stored as a hash
810reference. When a role is composed into a class, this hash reference
811is passed directly to the metaclass's C<add_attribute> method.
812
813This is quite likely to change in the future.
814
e185c027 815=over 4
816
705d4cfd 817=item B<< $metarole->get_attribute($attribute_name) >>
818
819=item B<< $metarole->has_attribute($attribute_name) >>
1331430a 820
705d4cfd 821=item B<< $metarole->get_attribute_list >>
1331430a 822
705d4cfd 823=item B<< $metarole->add_attribute($name, %options) >>
1331430a 824
705d4cfd 825=item B<< $metarole->remove_attribute($attribute_name) >>
1331430a 826
827=back
828
705d4cfd 829=head2 Required methods
830
0558683c 831=over 4
832
705d4cfd 833=item B<< $metarole->get_required_method_list >>
0558683c 834
705d4cfd 835Returns the list of methods required by the role.
0558683c 836
705d4cfd 837=item B<< $metarole->requires_method($name) >>
0558683c 838
705d4cfd 839Returns true if the role requires the named method.
0558683c 840
0ecff16b 841=item B<< $metarole->add_required_methods(@names) >>
0558683c 842
b3c1586a 843Adds the named methods to the role's list of required methods.
0558683c 844
705d4cfd 845=item B<< $metarole->remove_required_methods(@names) >>
0558683c 846
2dda1d28 847Removes the named methods from the role's list of required methods.
0558683c 848
bb153262 849=item B<< $metarole->add_conflicting_method(%params) >>
09eeab06 850
bb153262 851Instantiate the parameters as a L<Moose::Meta::Role::Method::Conflicting>
09eeab06 852object, then add it to the required method list.
853
705d4cfd 854=back
855
856=head2 Method modifiers
0558683c 857
705d4cfd 858These methods act like their counterparts in L<Class::Mop::Class> and
859L<Moose::Meta::Class>.
860
861However, method modifiers are simply stored internally, and are not
862applied until the role itself is applied to a class.
0558683c 863
864=over 4
865
705d4cfd 866=item B<< $metarole->add_after_method_modifier($method_name, $method) >>
0558683c 867
705d4cfd 868=item B<< $metarole->add_around_method_modifier($method_name, $method) >>
0558683c 869
705d4cfd 870=item B<< $metarole->add_before_method_modifier($method_name, $method) >>
0558683c 871
705d4cfd 872=item B<< $metarole->add_override_method_modifier($method_name, $method) >>
0558683c 873
705d4cfd 874These methods all add an appropriate modifier to the internal list of
875modifiers.
0558683c 876
705d4cfd 877=item B<< $metarole->has_after_method_modifiers >>
0558683c 878
705d4cfd 879=item B<< $metarole->has_around_method_modifiers >>
880
881=item B<< $metarole->has_before_method_modifiers >>
882
883=item B<< $metarole->has_override_method_modifier >>
0558683c 884
705d4cfd 885Return true if the role has any modifiers of the given type.
0558683c 886
705d4cfd 887=item B<< $metarole->get_after_method_modifiers($method_name) >>
0558683c 888
705d4cfd 889=item B<< $metarole->get_around_method_modifiers($method_name) >>
0558683c 890
705d4cfd 891=item B<< $metarole->get_before_method_modifiers($method_name) >>
0558683c 892
705d4cfd 893Given a method name, returns a list of the appropriate modifiers for
894that method.
895
896=item B<< $metarole->get_override_method_modifier($method_name) >>
897
898Given a method name, returns the override method modifier for that
899method, if it has one.
0558683c 900
901=back
902
705d4cfd 903=head2 Introspection
505065c4 904
705d4cfd 905=over 4
505065c4 906
705d4cfd 907=item B<< Moose::Meta::Role->meta >>
505065c4 908
705d4cfd 909This will return a L<Class::MOP::Class> instance for this class.
505065c4 910
911=back
912
e185c027 913=head1 BUGS
914
fb1e11d5 915All complex software has bugs lurking in it, and this module is no
e185c027 916exception. If you find a bug please either email me, or add the bug
917to cpan-RT.
918
919=head1 AUTHOR
920
921Stevan Little E<lt>stevan@iinteractive.comE<gt>
922
923=head1 COPYRIGHT AND LICENSE
924
2840a3b2 925Copyright 2006-2009 by Infinity Interactive, Inc.
e185c027 926
927L<http://www.iinteractive.com>
928
929This library is free software; you can redistribute it and/or modify
fb1e11d5 930it under the same terms as Perl itself.
e185c027 931
b8aeb4dc 932=cut