Commit | Line | Data |
c0e30cf5 |
1 | |
2 | package Moose::Meta::Attribute; |
3 | |
4 | use strict; |
5 | use warnings; |
6 | |
9238220f |
7 | use Class::MOP (); |
21f1e231 |
8 | use Scalar::Util 'blessed', 'weaken'; |
fe11f190 |
9 | use List::MoreUtils 'any'; |
1454efcc |
10 | use Try::Tiny; |
a909a4df |
11 | use overload (); |
a15dff8d |
12 | |
d874ffad |
13 | our $VERSION = '1.20'; |
d44714be |
14 | our $AUTHORITY = 'cpan:STEVAN'; |
78cd1d3b |
15 | |
f1309155 |
16 | use Moose::Deprecated; |
8ee73eeb |
17 | use Moose::Meta::Method::Accessor; |
a05f85c1 |
18 | use Moose::Meta::Method::Delegation; |
d5c30e52 |
19 | use Moose::Util (); |
a3c7e2fe |
20 | use Moose::Util::TypeConstraints (); |
d2782813 |
21 | use Class::MOP::MiniTrait; |
bc1e29b5 |
22 | |
f785aad8 |
23 | use base 'Class::MOP::Attribute', 'Moose::Meta::Mixin::AttributeCore'; |
c0e30cf5 |
24 | |
d2782813 |
25 | Class::MOP::MiniTrait::apply(__PACKAGE__, 'Moose::Meta::Object::Trait'); |
26 | |
82a5b1a7 |
27 | __PACKAGE__->meta->add_attribute('traits' => ( |
28 | reader => 'applied_traits', |
29 | predicate => 'has_applied_traits', |
30 | )); |
82168dbb |
31 | |
d03bd989 |
32 | # we need to have a ->does method in here to |
33 | # more easily support traits, and the introspection |
0db4f1d7 |
34 | # of those traits. We extend the does check to look |
35 | # for metatrait aliases. |
36 | sub does { |
37 | my ($self, $role_name) = @_; |
1454efcc |
38 | my $name = try { |
0db4f1d7 |
39 | Moose::Util::resolve_metatrait_alias(Attribute => $role_name) |
40 | }; |
41 | return 0 if !defined($name); # failed to load class |
e8895723 |
42 | return $self->Moose::Object::does($name); |
0db4f1d7 |
43 | } |
587e457d |
44 | |
be05faea |
45 | sub throw_error { |
46 | my $self = shift; |
47 | my $class = ( ref $self && $self->associated_class ) || "Moose::Meta::Class"; |
48 | unshift @_, "message" if @_ % 2 == 1; |
49 | unshift @_, attr => $self if ref $self; |
50 | unshift @_, $class; |
18748ad6 |
51 | my $handler = $class->can("throw_error"); # to avoid incrementing depth by 1 |
52 | goto $handler; |
be05faea |
53 | } |
54 | |
78cd1d3b |
55 | sub new { |
f3c4e20e |
56 | my ($class, $name, %options) = @_; |
c32c2c61 |
57 | $class->_process_options($name, \%options) unless $options{__hack_no_process_options}; # used from clone()... YECHKKK FIXME ICKY YUCK GROSS |
aa4c3a8d |
58 | |
59 | delete $options{__hack_no_process_options}; |
60 | |
61 | my %attrs = |
62 | ( map { $_ => 1 } |
63 | grep { defined } |
64 | map { $_->init_arg() } |
65 | $class->meta()->get_all_attributes() |
66 | ); |
67 | |
68 | my @bad = sort grep { ! $attrs{$_} } keys %options; |
69 | |
70 | if (@bad) |
71 | { |
72 | Carp::cluck "Found unknown argument(s) passed to '$name' attribute constructor in '$class': @bad"; |
73 | } |
74 | |
f3c4e20e |
75 | return $class->SUPER::new($name, %options); |
1d768fb1 |
76 | } |
77 | |
d5c30e52 |
78 | sub interpolate_class_and_new { |
aa4c3a8d |
79 | my ($class, $name, %args) = @_; |
d5c30e52 |
80 | |
aa4c3a8d |
81 | my ( $new_class, @traits ) = $class->interpolate_class(\%args); |
d03bd989 |
82 | |
aa4c3a8d |
83 | $new_class->new($name, %args, ( scalar(@traits) ? ( traits => \@traits ) : () ) ); |
d5c30e52 |
84 | } |
85 | |
86 | sub interpolate_class { |
aa4c3a8d |
87 | my ($class, $options) = @_; |
d5c30e52 |
88 | |
c32c2c61 |
89 | $class = ref($class) || $class; |
90 | |
aa4c3a8d |
91 | if ( my $metaclass_name = delete $options->{metaclass} ) { |
c32c2c61 |
92 | my $new_class = Moose::Util::resolve_metaclass_alias( Attribute => $metaclass_name ); |
d03bd989 |
93 | |
c32c2c61 |
94 | if ( $class ne $new_class ) { |
95 | if ( $new_class->can("interpolate_class") ) { |
aa4c3a8d |
96 | return $new_class->interpolate_class($options); |
c32c2c61 |
97 | } else { |
98 | $class = $new_class; |
99 | } |
100 | } |
d5c30e52 |
101 | } |
102 | |
c32c2c61 |
103 | my @traits; |
104 | |
aa4c3a8d |
105 | if (my $traits = $options->{traits}) { |
8974015d |
106 | my $i = 0; |
107 | while ($i < @$traits) { |
108 | my $trait = $traits->[$i++]; |
109 | next if ref($trait); # options to a trait we discarded |
110 | |
111 | $trait = Moose::Util::resolve_metatrait_alias(Attribute => $trait) |
112 | || $trait; |
113 | |
114 | next if $class->does($trait); |
115 | |
116 | push @traits, $trait; |
117 | |
118 | # are there options? |
119 | push @traits, $traits->[$i++] |
120 | if $traits->[$i] && ref($traits->[$i]); |
121 | } |
965743fb |
122 | |
123 | if (@traits) { |
c32c2c61 |
124 | my $anon_class = Moose::Meta::Class->create_anon_class( |
125 | superclasses => [ $class ], |
126 | roles => [ @traits ], |
127 | cache => 1, |
128 | ); |
129 | |
130 | $class = $anon_class->name; |
131 | } |
d5c30e52 |
132 | } |
c32c2c61 |
133 | |
134 | return ( wantarray ? ( $class, @traits ) : $class ); |
d5c30e52 |
135 | } |
136 | |
e606ae5f |
137 | # ... |
138 | |
ec835085 |
139 | # method-generating options shouldn't be overridden |
140 | sub illegal_options_for_inheritance { |
d21262bd |
141 | qw(reader writer accessor clearer predicate) |
ec835085 |
142 | } |
e606ae5f |
143 | |
144 | # NOTE/TODO |
d03bd989 |
145 | # This method *must* be able to handle |
146 | # Class::MOP::Attribute instances as |
147 | # well. Yes, I know that is wrong, but |
148 | # apparently we didn't realize it was |
149 | # doing that and now we have some code |
150 | # which is dependent on it. The real |
151 | # solution of course is to push this |
e606ae5f |
152 | # feature back up into Class::MOP::Attribute |
153 | # but I not right now, I am too lazy. |
d03bd989 |
154 | # However if you are reading this and |
155 | # looking for something to do,.. please |
e606ae5f |
156 | # be my guest. |
157 | # - stevan |
ce0e8d63 |
158 | sub clone_and_inherit_options { |
159 | my ($self, %options) = @_; |
d03bd989 |
160 | |
e606ae5f |
161 | # NOTE: |
162 | # we may want to extends a Class::MOP::Attribute |
d03bd989 |
163 | # in which case we need to be able to use the |
164 | # core set of legal options that have always |
e606ae5f |
165 | # been here. But we allows Moose::Meta::Attribute |
166 | # instances to changes them. |
167 | # - SL |
7782e1da |
168 | my @illegal_options = $self->can('illegal_options_for_inheritance') |
169 | ? $self->illegal_options_for_inheritance |
170 | : (); |
171 | |
ec835085 |
172 | my @found_illegal_options = grep { exists $options{$_} && exists $self->{$_} ? $_ : undef } @illegal_options; |
7782e1da |
173 | (scalar @found_illegal_options == 0) |
174 | || $self->throw_error("Illegal inherited options => (" . (join ', ' => @found_illegal_options) . ")", data => \%options); |
26fbace8 |
175 | |
ce0e8d63 |
176 | if ($options{isa}) { |
177 | my $type_constraint; |
8de73ff1 |
178 | if (blessed($options{isa}) && $options{isa}->isa('Moose::Meta::TypeConstraint')) { |
179 | $type_constraint = $options{isa}; |
180 | } |
181 | else { |
d40ce9d5 |
182 | $type_constraint = Moose::Util::TypeConstraints::find_or_create_isa_type_constraint($options{isa}); |
8de73ff1 |
183 | (defined $type_constraint) |
be05faea |
184 | || $self->throw_error("Could not find the type constraint '" . $options{isa} . "'", data => $options{isa}); |
8de73ff1 |
185 | } |
5e98d2b6 |
186 | |
7782e1da |
187 | $options{type_constraint} = $type_constraint; |
ce0e8d63 |
188 | } |
d03bd989 |
189 | |
2ea379cb |
190 | if ($options{does}) { |
191 | my $type_constraint; |
192 | if (blessed($options{does}) && $options{does}->isa('Moose::Meta::TypeConstraint')) { |
193 | $type_constraint = $options{does}; |
194 | } |
195 | else { |
d40ce9d5 |
196 | $type_constraint = Moose::Util::TypeConstraints::find_or_create_does_type_constraint($options{does}); |
2ea379cb |
197 | (defined $type_constraint) |
be05faea |
198 | || $self->throw_error("Could not find the type constraint '" . $options{does} . "'", data => $options{does}); |
2ea379cb |
199 | } |
200 | |
7782e1da |
201 | $options{type_constraint} = $type_constraint; |
d03bd989 |
202 | } |
c32c2c61 |
203 | |
cbd141ca |
204 | # NOTE: |
d03bd989 |
205 | # this doesn't apply to Class::MOP::Attributes, |
cbd141ca |
206 | # so we can ignore it for them. |
207 | # - SL |
208 | if ($self->can('interpolate_class')) { |
7782e1da |
209 | ( $options{metaclass}, my @traits ) = $self->interpolate_class(\%options); |
c32c2c61 |
210 | |
cbd141ca |
211 | my %seen; |
212 | my @all_traits = grep { $seen{$_}++ } @{ $self->applied_traits || [] }, @traits; |
7782e1da |
213 | $options{traits} = \@all_traits if @all_traits; |
cbd141ca |
214 | } |
c32c2c61 |
215 | |
d412262b |
216 | # This method can be called on a CMOP::Attribute object, so we need to |
1aefb264 |
217 | # make sure we can call this method. |
218 | $self->_process_lazy_build_option( $self->name, \%options ) |
219 | if $self->can('_process_lazy_build_option'); |
4a8c7092 |
220 | |
7782e1da |
221 | $self->clone(%options); |
1d768fb1 |
222 | } |
223 | |
c32c2c61 |
224 | sub clone { |
225 | my ( $self, %params ) = @_; |
226 | |
aa4c3a8d |
227 | my $class = delete $params{metaclass} || ref $self; |
c32c2c61 |
228 | |
db72153d |
229 | my ( @init, @non_init ); |
c32c2c61 |
230 | |
0772362a |
231 | foreach my $attr ( grep { $_->has_value($self) } Class::MOP::class_of($self)->get_all_attributes ) { |
db72153d |
232 | push @{ $attr->has_init_arg ? \@init : \@non_init }, $attr; |
233 | } |
c32c2c61 |
234 | |
db72153d |
235 | my %new_params = ( ( map { $_->init_arg => $_->get_value($self) } @init ), %params ); |
c32c2c61 |
236 | |
db72153d |
237 | my $name = delete $new_params{name}; |
c32c2c61 |
238 | |
db72153d |
239 | my $clone = $class->new($name, %new_params, __hack_no_process_options => 1 ); |
c32c2c61 |
240 | |
db72153d |
241 | foreach my $attr ( @non_init ) { |
242 | $attr->set_value($clone, $attr->get_value($self)); |
c32c2c61 |
243 | } |
db72153d |
244 | |
245 | return $clone; |
c32c2c61 |
246 | } |
247 | |
1d768fb1 |
248 | sub _process_options { |
1aefb264 |
249 | my ( $class, $name, $options ) = @_; |
8de73ff1 |
250 | |
1aefb264 |
251 | $class->_process_is_option( $name, $options ); |
252 | $class->_process_isa_option( $name, $options ); |
253 | $class->_process_does_option( $name, $options ); |
254 | $class->_process_coerce_option( $name, $options ); |
255 | $class->_process_trigger_option( $name, $options ); |
256 | $class->_process_auto_deref_option( $name, $options ); |
257 | $class->_process_lazy_build_option( $name, $options ); |
258 | $class->_process_lazy_option( $name, $options ); |
259 | $class->_process_required_option( $name, $options ); |
260 | } |
21f1e231 |
261 | |
1aefb264 |
262 | sub _process_is_option { |
263 | my ( $class, $name, $options ) = @_; |
d03bd989 |
264 | |
1aefb264 |
265 | return unless $options->{is}; |
266 | |
267 | ### ------------------------- |
268 | ## is => ro, writer => _foo # turns into (reader => foo, writer => _foo) as before |
269 | ## is => rw, writer => _foo # turns into (reader => foo, writer => _foo) |
270 | ## is => rw, accessor => _foo # turns into (accessor => _foo) |
271 | ## is => ro, accessor => _foo # error, accesor is rw |
272 | ### ------------------------- |
273 | |
274 | if ( $options->{is} eq 'ro' ) { |
275 | $class->throw_error( |
276 | "Cannot define an accessor name on a read-only attribute, accessors are read/write", |
277 | data => $options ) |
278 | if exists $options->{accessor}; |
279 | $options->{reader} ||= $name; |
280 | } |
281 | elsif ( $options->{is} eq 'rw' ) { |
282 | if ( $options->{writer} ) { |
8de73ff1 |
283 | $options->{reader} ||= $name; |
8de73ff1 |
284 | } |
8de73ff1 |
285 | else { |
1aefb264 |
286 | $options->{accessor} ||= $name; |
8de73ff1 |
287 | } |
f3c4e20e |
288 | } |
1aefb264 |
289 | elsif ( $options->{is} eq 'bare' ) { |
290 | return; |
291 | # do nothing, but don't complain (later) about missing methods |
292 | } |
293 | else { |
294 | $class->throw_error( "I do not understand this option (is => " |
295 | . $options->{is} |
296 | . ") on attribute ($name)", data => $options->{is} ); |
297 | } |
298 | } |
8de73ff1 |
299 | |
1aefb264 |
300 | sub _process_isa_option { |
301 | my ( $class, $name, $options ) = @_; |
302 | |
303 | return unless exists $options->{isa}; |
8de73ff1 |
304 | |
1aefb264 |
305 | if ( exists $options->{does} ) { |
306 | if ( try { $options->{isa}->can('does') } ) { |
307 | ( $options->{isa}->does( $options->{does} ) ) |
308 | || $class->throw_error( |
309 | "Cannot have an isa option and a does option if the isa does not do the does on attribute ($name)", |
310 | data => $options ); |
8de73ff1 |
311 | } |
312 | else { |
1aefb264 |
313 | $class->throw_error( |
314 | "Cannot have an isa option which cannot ->does() on attribute ($name)", |
315 | data => $options ); |
8de73ff1 |
316 | } |
f3c4e20e |
317 | } |
1aefb264 |
318 | |
319 | # allow for anon-subtypes here ... |
320 | if ( blessed( $options->{isa} ) |
321 | && $options->{isa}->isa('Moose::Meta::TypeConstraint') ) { |
322 | $options->{type_constraint} = $options->{isa}; |
323 | } |
324 | else { |
325 | $options->{type_constraint} |
326 | = Moose::Util::TypeConstraints::find_or_create_isa_type_constraint( |
327 | $options->{isa} ); |
f3c4e20e |
328 | } |
1aefb264 |
329 | } |
8de73ff1 |
330 | |
1aefb264 |
331 | sub _process_does_option { |
332 | my ( $class, $name, $options ) = @_; |
2b54d2a6 |
333 | |
1aefb264 |
334 | return unless exists $options->{does} && ! exists $options->{isa}; |
f1309155 |
335 | |
1aefb264 |
336 | # allow for anon-subtypes here ... |
337 | if ( blessed( $options->{does} ) |
338 | && $options->{does}->isa('Moose::Meta::TypeConstraint') ) { |
339 | $options->{type_constraint} = $options->{does}; |
f3c4e20e |
340 | } |
1aefb264 |
341 | else { |
342 | $options->{type_constraint} |
343 | = Moose::Util::TypeConstraints::find_or_create_does_type_constraint( |
344 | $options->{does} ); |
0b7df53c |
345 | } |
1aefb264 |
346 | } |
0b7df53c |
347 | |
1aefb264 |
348 | sub _process_coerce_option { |
349 | my ( $class, $name, $options ) = @_; |
8de73ff1 |
350 | |
1aefb264 |
351 | return unless $options->{coerce}; |
8de73ff1 |
352 | |
1aefb264 |
353 | ( exists $options->{type_constraint} ) |
354 | || $class->throw_error( |
355 | "You cannot have coercion without specifying a type constraint on attribute ($name)", |
356 | data => $options ); |
357 | |
358 | $class->throw_error( |
359 | "You cannot have a weak reference to a coerced value on attribute ($name)", |
360 | data => $options ) |
361 | if $options->{weak_ref}; |
26fbace8 |
362 | |
1aefb264 |
363 | unless ( $options->{type_constraint}->has_coercion ) { |
364 | my $type = $options->{type_constraint}->name; |
365 | |
366 | Moose::Deprecated::deprecated( |
367 | feature => 'coerce without coercion', |
368 | message => |
369 | "You cannot coerce an attribute ($name) unless its type ($type) has a coercion" |
370 | ); |
9edba990 |
371 | } |
1aefb264 |
372 | } |
373 | |
374 | sub _process_trigger_option { |
375 | my ( $class, $name, $options ) = @_; |
376 | |
377 | return unless exists $options->{trigger}; |
9edba990 |
378 | |
1aefb264 |
379 | ( 'CODE' eq ref $options->{trigger} ) |
380 | || $class->throw_error("Trigger must be a CODE ref on attribute ($name)", data => $options->{trigger}); |
78cd1d3b |
381 | } |
c0e30cf5 |
382 | |
1aefb264 |
383 | sub _process_auto_deref_option { |
384 | my ( $class, $name, $options ) = @_; |
385 | |
386 | return unless $options->{auto_deref}; |
387 | |
388 | ( exists $options->{type_constraint} ) |
389 | || $class->throw_error( |
390 | "You cannot auto-dereference without specifying a type constraint on attribute ($name)", |
391 | data => $options ); |
392 | |
393 | ( $options->{type_constraint}->is_a_type_of('ArrayRef') |
394 | || $options->{type_constraint}->is_a_type_of('HashRef') ) |
395 | || $class->throw_error( |
396 | "You cannot auto-dereference anything other than a ArrayRef or HashRef on attribute ($name)", |
397 | data => $options ); |
398 | } |
399 | |
400 | sub _process_lazy_build_option { |
4a8c7092 |
401 | my ( $class, $name, $options ) = @_; |
402 | |
403 | return unless $options->{lazy_build}; |
404 | |
405 | $class->throw_error( |
406 | "You can not use lazy_build and default for the same attribute ($name)", |
407 | data => $options ) |
408 | if exists $options->{default}; |
409 | |
410 | $options->{lazy} = 1; |
411 | $options->{builder} ||= "_build_${name}"; |
1aefb264 |
412 | |
4a8c7092 |
413 | if ( $name =~ /^_/ ) { |
414 | $options->{clearer} ||= "_clear${name}"; |
415 | $options->{predicate} ||= "_has${name}"; |
416 | } |
417 | else { |
418 | $options->{clearer} ||= "clear_${name}"; |
419 | $options->{predicate} ||= "has_${name}"; |
420 | } |
421 | } |
422 | |
1aefb264 |
423 | sub _process_lazy_option { |
424 | my ( $class, $name, $options ) = @_; |
425 | |
426 | return unless $options->{lazy}; |
427 | |
428 | ( exists $options->{default} || defined $options->{builder} ) |
429 | || $class->throw_error( |
430 | "You cannot have a lazy attribute ($name) without specifying a default value for it", |
431 | data => $options ); |
432 | } |
433 | |
434 | sub _process_required_option { |
435 | my ( $class, $name, $options ) = @_; |
436 | |
437 | if ( |
438 | $options->{required} |
439 | && !( |
440 | ( !exists $options->{init_arg} || defined $options->{init_arg} ) |
441 | || exists $options->{default} |
442 | || defined $options->{builder} |
443 | ) |
444 | ) { |
445 | $class->throw_error( |
446 | "You cannot have a required attribute ($name) without a default, builder, or an init_arg", |
447 | data => $options ); |
448 | } |
449 | } |
450 | |
d500266f |
451 | sub initialize_instance_slot { |
ddd0ec20 |
452 | my ($self, $meta_instance, $instance, $params) = @_; |
d500266f |
453 | my $init_arg = $self->init_arg(); |
454 | # try to fetch the init arg from the %params ... |
ddd0ec20 |
455 | |
26fbace8 |
456 | my $val; |
1ed0b94f |
457 | my $value_is_set; |
625d571f |
458 | if ( defined($init_arg) and exists $params->{$init_arg}) { |
d500266f |
459 | $val = $params->{$init_arg}; |
d03bd989 |
460 | $value_is_set = 1; |
d500266f |
461 | } |
462 | else { |
463 | # skip it if it's lazy |
464 | return if $self->is_lazy; |
465 | # and die if it's required and doesn't have a default value |
be05faea |
466 | $self->throw_error("Attribute (" . $self->name . ") is required", object => $instance, data => $params) |
26fbace8 |
467 | if $self->is_required && !$self->has_default && !$self->has_builder; |
ddd0ec20 |
468 | |
1ed0b94f |
469 | # if nothing was in the %params, we can use the |
470 | # attribute's default value (if it has one) |
471 | if ($self->has_default) { |
472 | $val = $self->default($instance); |
473 | $value_is_set = 1; |
d03bd989 |
474 | } |
a6c84c69 |
475 | elsif ($self->has_builder) { |
e606ae5f |
476 | $val = $self->_call_builder($instance); |
477 | $value_is_set = 1; |
a0748c37 |
478 | } |
26fbace8 |
479 | } |
480 | |
1ed0b94f |
481 | return unless $value_is_set; |
482 | |
9c9563c7 |
483 | $val = $self->_coerce_and_verify( $val, $instance ); |
ddd0ec20 |
484 | |
759e4e8f |
485 | $self->set_initial_value($instance, $val); |
312e0f0c |
486 | |
487 | if ( ref $val && $self->is_weak_ref ) { |
32881f68 |
488 | $self->_weaken_value($instance); |
312e0f0c |
489 | } |
d500266f |
490 | } |
491 | |
e606ae5f |
492 | sub _call_builder { |
493 | my ( $self, $instance ) = @_; |
494 | |
495 | my $builder = $self->builder(); |
496 | |
497 | return $instance->$builder() |
498 | if $instance->can( $self->builder ); |
499 | |
500 | $self->throw_error( blessed($instance) |
501 | . " does not support builder method '" |
502 | . $self->builder |
503 | . "' for attribute '" |
504 | . $self->name |
505 | . "'", |
506 | object => $instance, |
507 | ); |
508 | } |
509 | |
d617b644 |
510 | ## Slot management |
9e93dd19 |
511 | |
8abe9636 |
512 | # FIXME: |
d03bd989 |
513 | # this duplicates too much code from |
514 | # Class::MOP::Attribute, we need to |
8abe9636 |
515 | # refactor these bits eventually. |
516 | # - SL |
517 | sub _set_initial_slot_value { |
518 | my ($self, $meta_instance, $instance, $value) = @_; |
519 | |
520 | my $slot_name = $self->name; |
521 | |
522 | return $meta_instance->set_slot_value($instance, $slot_name, $value) |
523 | unless $self->has_initializer; |
524 | |
8abe9636 |
525 | my $callback = sub { |
9c9563c7 |
526 | my $val = $self->_coerce_and_verify( shift, $instance );; |
527 | |
8abe9636 |
528 | $meta_instance->set_slot_value($instance, $slot_name, $val); |
529 | }; |
d03bd989 |
530 | |
8abe9636 |
531 | my $initializer = $self->initializer; |
532 | |
533 | # most things will just want to set a value, so make it first arg |
534 | $instance->$initializer($value, $callback, $self); |
535 | } |
536 | |
946289d1 |
537 | sub set_value { |
b6af66f8 |
538 | my ($self, $instance, @args) = @_; |
539 | my $value = $args[0]; |
26fbace8 |
540 | |
946289d1 |
541 | my $attr_name = $self->name; |
26fbace8 |
542 | |
b6af66f8 |
543 | if ($self->is_required and not @args) { |
be05faea |
544 | $self->throw_error("Attribute ($attr_name) is required", object => $instance); |
946289d1 |
545 | } |
26fbace8 |
546 | |
9c9563c7 |
547 | $value = $self->_coerce_and_verify( $value, $instance ); |
26fbace8 |
548 | |
3dda07f5 |
549 | my @old; |
550 | if ( $self->has_trigger && $self->has_value($instance) ) { |
551 | @old = $self->get_value($instance, 'for trigger'); |
552 | } |
553 | |
312e0f0c |
554 | $self->SUPER::set_value($instance, $value); |
26fbace8 |
555 | |
312e0f0c |
556 | if ( ref $value && $self->is_weak_ref ) { |
32881f68 |
557 | $self->_weaken_value($instance); |
946289d1 |
558 | } |
26fbace8 |
559 | |
946289d1 |
560 | if ($self->has_trigger) { |
3dda07f5 |
561 | $self->trigger->($instance, $value, @old); |
946289d1 |
562 | } |
563 | } |
564 | |
32881f68 |
565 | sub _weaken_value { |
312e0f0c |
566 | my ( $self, $instance ) = @_; |
567 | |
32881f68 |
568 | my $meta_instance = Class::MOP::Class->initialize( blessed($instance) ) |
569 | ->get_meta_instance; |
312e0f0c |
570 | |
571 | $meta_instance->weaken_slot_value( $instance, $self->name ); |
572 | } |
573 | |
946289d1 |
574 | sub get_value { |
3dda07f5 |
575 | my ($self, $instance, $for_trigger) = @_; |
26fbace8 |
576 | |
946289d1 |
577 | if ($self->is_lazy) { |
8de73ff1 |
578 | unless ($self->has_value($instance)) { |
e606ae5f |
579 | my $value; |
8de73ff1 |
580 | if ($self->has_default) { |
e606ae5f |
581 | $value = $self->default($instance); |
3f11800d |
582 | } elsif ( $self->has_builder ) { |
e606ae5f |
583 | $value = $self->_call_builder($instance); |
584 | } |
9c9563c7 |
585 | |
586 | $value = $self->_coerce_and_verify( $value, $instance ); |
587 | |
e606ae5f |
588 | $self->set_initial_value($instance, $value); |
8de73ff1 |
589 | } |
946289d1 |
590 | } |
26fbace8 |
591 | |
3dda07f5 |
592 | if ( $self->should_auto_deref && ! $for_trigger ) { |
26fbace8 |
593 | |
946289d1 |
594 | my $type_constraint = $self->type_constraint; |
595 | |
596 | if ($type_constraint->is_a_type_of('ArrayRef')) { |
597 | my $rv = $self->SUPER::get_value($instance); |
598 | return unless defined $rv; |
599 | return wantarray ? @{ $rv } : $rv; |
26fbace8 |
600 | } |
946289d1 |
601 | elsif ($type_constraint->is_a_type_of('HashRef')) { |
602 | my $rv = $self->SUPER::get_value($instance); |
603 | return unless defined $rv; |
604 | return wantarray ? %{ $rv } : $rv; |
26fbace8 |
605 | } |
946289d1 |
606 | else { |
46cb090f |
607 | $self->throw_error("Can not auto de-reference the type constraint '" . $type_constraint->name . "'", object => $instance, type_constraint => $type_constraint); |
946289d1 |
608 | } |
26fbace8 |
609 | |
946289d1 |
610 | } |
611 | else { |
26fbace8 |
612 | |
946289d1 |
613 | return $self->SUPER::get_value($instance); |
26fbace8 |
614 | } |
946289d1 |
615 | } |
a15dff8d |
616 | |
26fbace8 |
617 | ## installing accessors |
c0e30cf5 |
618 | |
246bbeef |
619 | sub accessor_metaclass { 'Moose::Meta::Method::Accessor' } |
620 | |
621 | sub install_accessors { |
ae907ae0 |
622 | my $self = shift; |
246bbeef |
623 | $self->SUPER::install_accessors(@_); |
624 | $self->install_delegation if $self->has_handles; |
28af3424 |
625 | return; |
626 | } |
627 | |
9340e346 |
628 | sub _check_associated_methods { |
28af3424 |
629 | my $self = shift; |
86cf196b |
630 | unless ( |
0bbd378f |
631 | @{ $self->associated_methods } |
86cf196b |
632 | || ($self->_is_metadata || '') eq 'bare' |
633 | ) { |
634 | Carp::cluck( |
8f4450f3 |
635 | 'Attribute (' . $self->name . ') of class ' |
636 | . $self->associated_class->name |
637 | . ' has no associated methods' |
86cf196b |
638 | . ' (did you mean to provide an "is" argument?)' |
639 | . "\n" |
640 | ) |
641 | } |
e606ae5f |
642 | } |
26fbace8 |
643 | |
3b6e2290 |
644 | sub _process_accessors { |
645 | my $self = shift; |
646 | my ($type, $accessor, $generate_as_inline_methods) = @_; |
837f61c9 |
647 | |
648 | $accessor = ( keys %$accessor )[0] if ( ref($accessor) || '' ) eq 'HASH'; |
99541dfd |
649 | my $method = $self->associated_class->get_method($accessor); |
837f61c9 |
650 | |
d7dfe605 |
651 | if ( $method |
652 | && $method->isa('Class::MOP::Method::Accessor') |
653 | && $method->associated_attribute->name ne $self->name ) { |
654 | |
655 | my $other_attr_name = $method->associated_attribute->name; |
656 | my $name = $self->name; |
657 | |
658 | Carp::cluck( |
659 | "You are overwriting an accessor ($accessor) for the $other_attr_name attribute" |
660 | . " with a new accessor method for the $name attribute" ); |
661 | } |
662 | |
837f61c9 |
663 | if ( |
664 | $method |
665 | && !$method->isa('Class::MOP::Method::Accessor') |
666 | && ( !$self->definition_context |
667 | || $method->package_name eq $self->definition_context->{package} ) |
668 | ) { |
669 | |
3b6e2290 |
670 | Carp::cluck( |
1d18c898 |
671 | "You are overwriting a locally defined method ($accessor) with " |
837f61c9 |
672 | . "an accessor" ); |
3b6e2290 |
673 | } |
d7dfe605 |
674 | |
837f61c9 |
675 | if ( !$self->associated_class->has_method($accessor) |
676 | && $self->associated_class->has_package_symbol( '&' . $accessor ) ) { |
677 | |
3968746e |
678 | Carp::cluck( |
679 | "You are overwriting a locally defined function ($accessor) with " |
837f61c9 |
680 | . "an accessor" ); |
3968746e |
681 | } |
837f61c9 |
682 | |
3b6e2290 |
683 | $self->SUPER::_process_accessors(@_); |
e606ae5f |
684 | } |
26fbace8 |
685 | |
e1d6f0a3 |
686 | sub remove_accessors { |
687 | my $self = shift; |
688 | $self->SUPER::remove_accessors(@_); |
689 | $self->remove_delegation if $self->has_handles; |
690 | return; |
691 | } |
692 | |
e06951bb |
693 | sub inline_set { |
d67398ab |
694 | my $self = shift; |
695 | my ( $instance, $value ) = @_; |
696 | |
697 | my $mi = $self->associated_class->get_meta_instance; |
698 | |
699 | my $code |
700 | = $mi->inline_set_slot_value( $instance, $self->slots, $value ) . ";"; |
701 | $code |
702 | .= $mi->inline_weaken_slot_value( $instance, $self->slots, $value ) |
6e642c8f |
703 | . " if ref $value;" |
d67398ab |
704 | if $self->is_weak_ref; |
705 | |
706 | return $code; |
707 | } |
708 | |
e606ae5f |
709 | sub install_delegation { |
710 | my $self = shift; |
26fbace8 |
711 | |
e606ae5f |
712 | # NOTE: |
713 | # Here we canonicalize the 'handles' option |
714 | # this will sort out any details and always |
715 | # return an hash of methods which we want |
716 | # to delagate to, see that method for details |
717 | my %handles = $self->_canonicalize_handles; |
718 | |
e606ae5f |
719 | |
720 | # install the delegation ... |
721 | my $associated_class = $self->associated_class; |
722 | foreach my $handle (keys %handles) { |
723 | my $method_to_call = $handles{$handle}; |
724 | my $class_name = $associated_class->name; |
725 | my $name = "${class_name}::${handle}"; |
26fbace8 |
726 | |
452bac1b |
727 | (!$associated_class->has_method($handle)) |
cee532a1 |
728 | || $self->throw_error("You cannot overwrite a locally defined method ($handle) with a delegation", method_name => $handle); |
26fbace8 |
729 | |
e606ae5f |
730 | # NOTE: |
731 | # handles is not allowed to delegate |
732 | # any of these methods, as they will |
733 | # override the ones in your class, which |
734 | # is almost certainly not what you want. |
4fe78472 |
735 | |
e606ae5f |
736 | # FIXME warn when $handle was explicitly specified, but not if the source is a regex or something |
737 | #cluck("Not delegating method '$handle' because it is a core method") and |
738 | next if $class_name->isa("Moose::Object") and $handle =~ /^BUILD|DEMOLISH$/ || Moose::Object->can($handle); |
26fbace8 |
739 | |
46f7e6a5 |
740 | my $method = $self->_make_delegation_method($handle, $method_to_call); |
a05f85c1 |
741 | |
742 | $self->associated_class->add_method($method->name, $method); |
0bbd378f |
743 | $self->associate_method($method); |
d03bd989 |
744 | } |
452bac1b |
745 | } |
746 | |
e1d6f0a3 |
747 | sub remove_delegation { |
748 | my $self = shift; |
749 | my %handles = $self->_canonicalize_handles; |
750 | my $associated_class = $self->associated_class; |
751 | foreach my $handle (keys %handles) { |
684323b3 |
752 | next unless any { $handle eq $_ } |
753 | map { $_->name } |
754 | @{ $self->associated_methods }; |
e1d6f0a3 |
755 | $self->associated_class->remove_method($handle); |
756 | } |
757 | } |
758 | |
98aae381 |
759 | # private methods to help delegation ... |
760 | |
452bac1b |
761 | sub _canonicalize_handles { |
762 | my $self = shift; |
763 | my $handles = $self->handles; |
c84f324f |
764 | if (my $handle_type = ref($handles)) { |
765 | if ($handle_type eq 'HASH') { |
766 | return %{$handles}; |
767 | } |
768 | elsif ($handle_type eq 'ARRAY') { |
769 | return map { $_ => $_ } @{$handles}; |
770 | } |
771 | elsif ($handle_type eq 'Regexp') { |
772 | ($self->has_type_constraint) |
0286711b |
773 | || $self->throw_error("Cannot delegate methods based on a Regexp without a type constraint (isa)", data => $handles); |
26fbace8 |
774 | return map { ($_ => $_) } |
c84f324f |
775 | grep { /$handles/ } $self->_get_delegate_method_list; |
776 | } |
777 | elsif ($handle_type eq 'CODE') { |
778 | return $handles->($self, $self->_find_delegate_metaclass); |
779 | } |
6cbf4a23 |
780 | elsif (blessed($handles) && $handles->isa('Moose::Meta::TypeConstraint::DuckType')) { |
781 | return map { $_ => $_ } @{ $handles->methods }; |
782 | } |
c7761602 |
783 | elsif (blessed($handles) && $handles->isa('Moose::Meta::TypeConstraint::Role')) { |
784 | $handles = $handles->role; |
785 | } |
c84f324f |
786 | else { |
be05faea |
787 | $self->throw_error("Unable to canonicalize the 'handles' option with $handles", data => $handles); |
c84f324f |
788 | } |
452bac1b |
789 | } |
c84f324f |
790 | |
c7761602 |
791 | Class::MOP::load_class($handles); |
792 | my $role_meta = Class::MOP::class_of($handles); |
d03bd989 |
793 | |
c7761602 |
794 | (blessed $role_meta && $role_meta->isa('Moose::Meta::Role')) |
795 | || $self->throw_error("Unable to canonicalize the 'handles' option with $handles because its metaclass is not a Moose::Meta::Role", data => $handles); |
796 | |
797 | return map { $_ => $_ } |
ba7d613d |
798 | map { $_->name } |
799 | grep { !$_->isa('Class::MOP::Method::Meta') } ( |
800 | $role_meta->_get_local_methods, |
801 | $role_meta->get_required_method_list, |
c7761602 |
802 | ); |
452bac1b |
803 | } |
804 | |
452bac1b |
805 | sub _get_delegate_method_list { |
806 | my $self = shift; |
807 | my $meta = $self->_find_delegate_metaclass; |
808 | if ($meta->isa('Class::MOP::Class')) { |
e606ae5f |
809 | return map { $_->name } # NOTE: !never! delegate &meta |
ba7d613d |
810 | grep { $_->package_name ne 'Moose::Object' && !$_->isa('Class::MOP::Method::Meta') } |
e606ae5f |
811 | $meta->get_all_methods; |
452bac1b |
812 | } |
813 | elsif ($meta->isa('Moose::Meta::Role')) { |
26fbace8 |
814 | return $meta->get_method_list; |
452bac1b |
815 | } |
816 | else { |
be05faea |
817 | $self->throw_error("Unable to recognize the delegate metaclass '$meta'", data => $meta); |
452bac1b |
818 | } |
819 | } |
820 | |
ccc2f11f |
821 | sub _find_delegate_metaclass { |
822 | my $self = shift; |
823 | if (my $class = $self->_isa_metadata) { |
9238220f |
824 | unless ( Class::MOP::is_class_loaded($class) ) { |
825 | $self->throw_error( |
826 | sprintf( |
827 | 'The %s attribute is trying to delegate to a class which has not been loaded - %s', |
828 | $self->name, $class |
829 | ) |
830 | ); |
831 | } |
ccc2f11f |
832 | # we might be dealing with a non-Moose class, |
833 | # and need to make our own metaclass. if there's |
834 | # already a metaclass, it will be returned |
835 | return Class::MOP::Class->initialize($class); |
836 | } |
837 | elsif (my $role = $self->_does_metadata) { |
9238220f |
838 | unless ( Class::MOP::is_class_loaded($class) ) { |
839 | $self->throw_error( |
840 | sprintf( |
841 | 'The %s attribute is trying to delegate to a role which has not been loaded - %s', |
842 | $self->name, $role |
843 | ) |
844 | ); |
845 | } |
846 | |
ccc2f11f |
847 | return Class::MOP::class_of($role); |
848 | } |
849 | else { |
850 | $self->throw_error("Cannot find delegate metaclass for attribute " . $self->name); |
851 | } |
852 | } |
853 | |
bd1226e2 |
854 | sub delegation_metaclass { 'Moose::Meta::Method::Delegation' } |
855 | |
a05f85c1 |
856 | sub _make_delegation_method { |
46f7e6a5 |
857 | my ( $self, $handle_name, $method_to_call ) = @_; |
a05f85c1 |
858 | |
3c573ca4 |
859 | my @curried_arguments; |
2de18801 |
860 | |
3c573ca4 |
861 | ($method_to_call, @curried_arguments) = @$method_to_call |
2de18801 |
862 | if 'ARRAY' eq ref($method_to_call); |
863 | |
bd1226e2 |
864 | return $self->delegation_metaclass->new( |
46f7e6a5 |
865 | name => $handle_name, |
866 | package_name => $self->associated_class->name, |
867 | attribute => $self, |
868 | delegate_to_method => $method_to_call, |
3c573ca4 |
869 | curried_arguments => \@curried_arguments, |
a05f85c1 |
870 | ); |
871 | } |
872 | |
9c9563c7 |
873 | sub _coerce_and_verify { |
874 | my $self = shift; |
875 | my $val = shift; |
876 | my $instance = shift; |
877 | |
878 | return $val unless $self->has_type_constraint; |
879 | |
2b54d2a6 |
880 | $val = $self->type_constraint->coerce($val) |
5aab256d |
881 | if $self->should_coerce && $self->type_constraint->has_coercion; |
9c9563c7 |
882 | |
883 | $self->verify_against_type_constraint($val, instance => $instance); |
884 | |
885 | return $val; |
886 | } |
887 | |
5755a9b2 |
888 | sub verify_against_type_constraint { |
2b86e02b |
889 | my $self = shift; |
890 | my $val = shift; |
891 | |
892 | return 1 if !$self->has_type_constraint; |
893 | |
894 | my $type_constraint = $self->type_constraint; |
895 | |
896 | $type_constraint->check($val) |
897 | || $self->throw_error("Attribute (" |
898 | . $self->name |
899 | . ") does not pass the type constraint because: " |
900 | . $type_constraint->get_message($val), data => $val, @_); |
901 | } |
902 | |
21f1e231 |
903 | package Moose::Meta::Attribute::Custom::Moose; |
904 | sub register_implementation { 'Moose::Meta::Attribute' } |
905 | |
c0e30cf5 |
906 | 1; |
907 | |
908 | __END__ |
909 | |
910 | =pod |
911 | |
912 | =head1 NAME |
913 | |
6ba6d68c |
914 | Moose::Meta::Attribute - The Moose attribute metaclass |
c0e30cf5 |
915 | |
916 | =head1 DESCRIPTION |
917 | |
93a708fd |
918 | This class is a subclass of L<Class::MOP::Attribute> that provides |
919 | additional Moose-specific functionality. |
6ba6d68c |
920 | |
7854b409 |
921 | To really understand this class, you will need to start with the |
922 | L<Class::MOP::Attribute> documentation. This class can be understood |
923 | as a set of additional features on top of the basic feature provided |
924 | by that parent class. |
e522431d |
925 | |
d4b1449e |
926 | =head1 INHERITANCE |
927 | |
928 | C<Moose::Meta::Attribute> is a subclass of L<Class::MOP::Attribute>. |
929 | |
c0e30cf5 |
930 | =head1 METHODS |
931 | |
93a708fd |
932 | Many of the documented below override methods in |
933 | L<Class::MOP::Attribute> and add Moose specific features. |
6ba6d68c |
934 | |
93a708fd |
935 | =head2 Creation |
6ba6d68c |
936 | |
c0e30cf5 |
937 | =over 4 |
938 | |
93a708fd |
939 | =item B<< Moose::Meta::Attribute->new(%options) >> |
c0e30cf5 |
940 | |
93a708fd |
941 | This method overrides the L<Class::MOP::Attribute> constructor. |
c32c2c61 |
942 | |
93a708fd |
943 | Many of the options below are described in more detail in the |
944 | L<Moose::Manual::Attributes> document. |
6e2840b7 |
945 | |
93a708fd |
946 | It adds the following options to the constructor: |
d500266f |
947 | |
93a708fd |
948 | =over 8 |
452bac1b |
949 | |
996b8c8d |
950 | =item * is => 'ro', 'rw', 'bare' |
e1d6f0a3 |
951 | |
93a708fd |
952 | This provides a shorthand for specifying the C<reader>, C<writer>, or |
953 | C<accessor> names. If the attribute is read-only ('ro') then it will |
954 | have a C<reader> method with the same attribute as the name. |
e606ae5f |
955 | |
93a708fd |
956 | If it is read-write ('rw') then it will have an C<accessor> method |
957 | with the same name. If you provide an explicit C<writer> for a |
958 | read-write attribute, then you will have a C<reader> with the same |
959 | name as the attribute, and a C<writer> with the name you provided. |
e1d6f0a3 |
960 | |
996b8c8d |
961 | Use 'bare' when you are deliberately not installing any methods |
962 | (accessor, reader, etc.) associated with this attribute; otherwise, |
963 | Moose will issue a deprecation warning when this attribute is added to a |
9340e346 |
964 | metaclass. |
996b8c8d |
965 | |
93a708fd |
966 | =item * isa => $type |
39b3bc94 |
967 | |
93a708fd |
968 | This option accepts a type. The type can be a string, which should be |
969 | a type name. If the type name is unknown, it is assumed to be a class |
970 | name. |
971 | |
972 | This option can also accept a L<Moose::Meta::TypeConstraint> object. |
973 | |
974 | If you I<also> provide a C<does> option, then your C<isa> option must |
975 | be a class name, and that class must do the role specified with |
976 | C<does>. |
977 | |
978 | =item * does => $role |
979 | |
980 | This is short-hand for saying that the attribute's type must be an |
981 | object which does the named role. |
982 | |
983 | =item * coerce => $bool |
984 | |
985 | This option is only valid for objects with a type constraint |
3b98ba07 |
986 | (C<isa>) that defined a coercion. If this is true, then coercions will be applied whenever |
93a708fd |
987 | this attribute is set. |
988 | |
989 | You can make both this and the C<weak_ref> option true. |
990 | |
991 | =item * trigger => $sub |
992 | |
993 | This option accepts a subroutine reference, which will be called after |
994 | the attribute is set. |
995 | |
996 | =item * required => $bool |
997 | |
998 | An attribute which is required must be provided to the constructor. An |
999 | attribute which is required can also have a C<default> or C<builder>, |
36741534 |
1000 | which will satisfy its required-ness. |
93a708fd |
1001 | |
1002 | A required attribute must have a C<default>, C<builder> or a |
1003 | non-C<undef> C<init_arg> |
1004 | |
1005 | =item * lazy => $bool |
1006 | |
1007 | A lazy attribute must have a C<default> or C<builder>. When an |
1008 | attribute is lazy, the default value will not be calculated until the |
1009 | attribute is read. |
1010 | |
1011 | =item * weak_ref => $bool |
1012 | |
1013 | If this is true, the attribute's value will be stored as a weak |
1014 | reference. |
1015 | |
1016 | =item * auto_deref => $bool |
1017 | |
1018 | If this is true, then the reader will dereference the value when it is |
1019 | called. The attribute must have a type constraint which defines the |
1020 | attribute as an array or hash reference. |
1021 | |
1022 | =item * lazy_build => $bool |
1023 | |
1024 | Setting this to true makes the attribute lazy and provides a number of |
1025 | default methods. |
1026 | |
1027 | has 'size' => ( |
1028 | is => 'ro', |
1029 | lazy_build => 1, |
1030 | ); |
1031 | |
1032 | is equivalent to this: |
1033 | |
1034 | has 'size' => ( |
1035 | is => 'ro', |
1036 | lazy => 1, |
1037 | builder => '_build_size', |
1038 | clearer => 'clear_size', |
1039 | predicate => 'has_size', |
1040 | ); |
1041 | |
ff39a83c |
1042 | |
1043 | If your attribute name starts with an underscore (C<_>), then the clearer |
1044 | and predicate will as well: |
1045 | |
1046 | has '_size' => ( |
1047 | is => 'ro', |
1048 | lazy_build => 1, |
1049 | ); |
1050 | |
1051 | becomes: |
1052 | |
1053 | has '_size' => ( |
1054 | is => 'ro', |
1055 | lazy => 1, |
1056 | builder => '_build__size', |
1057 | clearer => '_clear_size', |
1058 | predicate => '_has_size', |
1059 | ); |
1060 | |
1061 | Note the doubled underscore in the builder name. Internally, Moose |
1062 | simply prepends the attribute name with "_build_" to come up with the |
1063 | builder name. |
1064 | |
93a708fd |
1065 | =item * documentation |
1066 | |
1067 | An arbitrary string that can be retrieved later by calling C<< |
1068 | $attr->documentation >>. |
1069 | |
1070 | =back |
1071 | |
1072 | =item B<< $attr->clone(%options) >> |
1073 | |
1074 | This creates a new attribute based on attribute being cloned. You must |
1075 | supply a C<name> option to provide a new name for the attribute. |
1076 | |
1077 | The C<%options> can only specify options handled by |
1078 | L<Class::MOP::Attribute>. |
1079 | |
36741534 |
1080 | =back |
1081 | |
93a708fd |
1082 | =head2 Value management |
1083 | |
36741534 |
1084 | =over 4 |
1085 | |
93a708fd |
1086 | =item B<< $attr->initialize_instance_slot($meta_instance, $instance, $params) >> |
1087 | |
1088 | This method is used internally to initialize the attribute's slot in |
1089 | the object C<$instance>. |
1090 | |
1091 | This overrides the L<Class::MOP::Attribute> method to handle lazy |
1092 | attributes, weak references, and type constraints. |
bd1226e2 |
1093 | |
946289d1 |
1094 | =item B<get_value> |
1095 | |
1096 | =item B<set_value> |
1097 | |
6549b0d1 |
1098 | eval { $point->meta->get_attribute('x')->set_value($point, 'forty-two') }; |
bcbaa845 |
1099 | if($@) { |
1100 | print "Oops: $@\n"; |
1101 | } |
1102 | |
6549b0d1 |
1103 | I<Attribute (x) does not pass the type constraint (Int) with 'forty-two'> |
bcbaa845 |
1104 | |
1105 | Before setting the value, a check is made on the type constraint of |
1106 | the attribute, if it has one, to see if the value passes it. If the |
cec39889 |
1107 | value fails to pass, the set operation dies with a L</throw_error>. |
bcbaa845 |
1108 | |
1109 | Any coercion to convert values is done before checking the type constraint. |
1110 | |
1111 | To check a value against a type constraint before setting it, fetch the |
ec00fa75 |
1112 | attribute instance using L<Class::MOP::Class/find_attribute_by_name>, |
bcbaa845 |
1113 | fetch the type_constraint from the attribute using L<Moose::Meta::Attribute/type_constraint> |
e606ae5f |
1114 | and call L<Moose::Meta::TypeConstraint/check>. See L<Moose::Cookbook::Basics::Recipe4> |
bcbaa845 |
1115 | for an example. |
1116 | |
a15dff8d |
1117 | =back |
1118 | |
93a708fd |
1119 | =head2 Attribute Accessor generation |
6ba6d68c |
1120 | |
a15dff8d |
1121 | =over 4 |
1122 | |
93a708fd |
1123 | =item B<< $attr->install_accessors >> |
be05faea |
1124 | |
93a708fd |
1125 | This method overrides the parent to also install delegation methods. |
be05faea |
1126 | |
7a582117 |
1127 | If, after installing all methods, the attribute object has no associated |
1128 | methods, it throws an error unless C<< is => 'bare' >> was passed to the |
1129 | attribute constructor. (Trying to add an attribute that has no associated |
1130 | methods is almost always an error.) |
1131 | |
36741534 |
1132 | =item B<< $attr->remove_accessors >> |
d5c30e52 |
1133 | |
93a708fd |
1134 | This method overrides the parent to also remove delegation methods. |
d5c30e52 |
1135 | |
e06951bb |
1136 | =item B<< $attr->inline_set($instance_var, $value_var) >> |
d67398ab |
1137 | |
e06951bb |
1138 | This method return a code snippet suitable for inlining the relevant |
1139 | operation. It expect strings containing variable names to be used in the |
1140 | inlining, like C<'$self'> or C<'$_[1]'>. |
d67398ab |
1141 | |
93a708fd |
1142 | =item B<< $attr->install_delegation >> |
1143 | |
1144 | This method adds its delegation methods to the attribute's associated |
1145 | class, if it has any to add. |
1146 | |
1147 | =item B<< $attr->remove_delegation >> |
1148 | |
1149 | This method remove its delegation methods from the attribute's |
1150 | associated class. |
d5c30e52 |
1151 | |
93a708fd |
1152 | =item B<< $attr->accessor_metaclass >> |
9e93dd19 |
1153 | |
93a708fd |
1154 | Returns the accessor metaclass name, which defaults to |
1155 | L<Moose::Meta::Method::Accessor>. |
1156 | |
1157 | =item B<< $attr->delegation_metaclass >> |
1158 | |
1159 | Returns the delegation metaclass name, which defaults to |
1160 | L<Moose::Meta::Method::Delegation>. |
1161 | |
1162 | =back |
1163 | |
1164 | =head2 Additional Moose features |
1165 | |
1166 | These methods are not found in the superclass. They support features |
1167 | provided by Moose. |
1168 | |
36741534 |
1169 | =over 4 |
1170 | |
93a708fd |
1171 | =item B<< $attr->does($role) >> |
1172 | |
1173 | This indicates whether the I<attribute itself> does the given |
36741534 |
1174 | role. The role can be given as a full class name, or as a resolvable |
93a708fd |
1175 | trait name. |
1176 | |
1177 | Note that this checks the attribute itself, not its type constraint, |
1178 | so it is checking the attribute's metaclass and any traits applied to |
1179 | the attribute. |
1180 | |
1181 | =item B<< Moose::Meta::Class->interpolate_class_and_new($name, %options) >> |
1182 | |
1183 | This is an alternate constructor that handles the C<metaclass> and |
1184 | C<traits> options. |
9e93dd19 |
1185 | |
93a708fd |
1186 | Effectively, this method is a factory that finds or creates the |
36741534 |
1187 | appropriate class for the given C<metaclass> and/or C<traits>. |
e606ae5f |
1188 | |
93a708fd |
1189 | Once it has the appropriate class, it will call C<< $class->new($name, |
1190 | %options) >> on that class. |
e606ae5f |
1191 | |
93a708fd |
1192 | =item B<< $attr->clone_and_inherit_options(%options) >> |
a15dff8d |
1193 | |
93a708fd |
1194 | This method supports the C<has '+foo'> feature. It does various bits |
1195 | of processing on the supplied C<%options> before ultimately calling |
1196 | the C<clone> method. |
6ba6d68c |
1197 | |
93a708fd |
1198 | One of its main tasks is to make sure that the C<%options> provided |
7782e1da |
1199 | does not include the options returned by the |
1200 | C<illegal_options_for_inheritance> method. |
a15dff8d |
1201 | |
7782e1da |
1202 | =item B<< $attr->illegal_options_for_inheritance >> |
a15dff8d |
1203 | |
7782e1da |
1204 | This returns a blacklist of options that can not be overridden in a |
93a708fd |
1205 | subclass's attribute definition. |
2b86e02b |
1206 | |
93a708fd |
1207 | This exists to allow a custom metaclass to change or add to the list |
7782e1da |
1208 | of options which can not be changed. |
2b86e02b |
1209 | |
93a708fd |
1210 | =item B<< $attr->type_constraint >> |
452bac1b |
1211 | |
93a708fd |
1212 | Returns the L<Moose::Meta::TypeConstraint> object for this attribute, |
1213 | if it has one. |
452bac1b |
1214 | |
93a708fd |
1215 | =item B<< $attr->has_type_constraint >> |
452bac1b |
1216 | |
93a708fd |
1217 | Returns true if this attribute has a type constraint. |
452bac1b |
1218 | |
93a708fd |
1219 | =item B<< $attr->verify_against_type_constraint($value) >> |
a15dff8d |
1220 | |
93a708fd |
1221 | Given a value, this method returns true if the value is valid for the |
1222 | attribute's type constraint. If the value is not valid, it throws an |
1223 | error. |
4b598ea3 |
1224 | |
93a708fd |
1225 | =item B<< $attr->handles >> |
ca01a97b |
1226 | |
93a708fd |
1227 | This returns the value of the C<handles> option passed to the |
1228 | constructor. |
ca01a97b |
1229 | |
93a708fd |
1230 | =item B<< $attr->has_handles >> |
ca01a97b |
1231 | |
93a708fd |
1232 | Returns true if this attribute performs delegation. |
ca01a97b |
1233 | |
93a708fd |
1234 | =item B<< $attr->is_weak_ref >> |
26fbace8 |
1235 | |
93a708fd |
1236 | Returns true if this attribute stores its value as a weak reference. |
26fbace8 |
1237 | |
93a708fd |
1238 | =item B<< $attr->is_required >> |
26fbace8 |
1239 | |
93a708fd |
1240 | Returns true if this attribute is required to have a value. |
26fbace8 |
1241 | |
93a708fd |
1242 | =item B<< $attr->is_lazy >> |
58f85113 |
1243 | |
93a708fd |
1244 | Returns true if this attribute is lazy. |
26fbace8 |
1245 | |
93a708fd |
1246 | =item B<< $attr->is_lazy_build >> |
ca01a97b |
1247 | |
93a708fd |
1248 | Returns true if the C<lazy_build> option was true when passed to the |
1249 | constructor. |
4b598ea3 |
1250 | |
93a708fd |
1251 | =item B<< $attr->should_coerce >> |
6ba6d68c |
1252 | |
93a708fd |
1253 | Returns true if the C<coerce> option passed to the constructor was |
1254 | true. |
536f0b17 |
1255 | |
93a708fd |
1256 | =item B<< $attr->should_auto_deref >> |
536f0b17 |
1257 | |
93a708fd |
1258 | Returns true if the C<auto_deref> option passed to the constructor was |
1259 | true. |
536f0b17 |
1260 | |
93a708fd |
1261 | =item B<< $attr->trigger >> |
8c9d74e7 |
1262 | |
93a708fd |
1263 | This is the subroutine reference that was in the C<trigger> option |
1264 | passed to the constructor, if any. |
02a0fb52 |
1265 | |
36741534 |
1266 | =item B<< $attr->has_trigger >> |
8c9d74e7 |
1267 | |
93a708fd |
1268 | Returns true if this attribute has a trigger set. |
02a0fb52 |
1269 | |
93a708fd |
1270 | =item B<< $attr->documentation >> |
ddbdc0cb |
1271 | |
93a708fd |
1272 | Returns the value that was in the C<documentation> option passed to |
1273 | the constructor, if any. |
ddbdc0cb |
1274 | |
93a708fd |
1275 | =item B<< $attr->has_documentation >> |
ddbdc0cb |
1276 | |
93a708fd |
1277 | Returns true if this attribute has any documentation. |
ddbdc0cb |
1278 | |
93a708fd |
1279 | =item B<< $attr->applied_traits >> |
88f23977 |
1280 | |
93a708fd |
1281 | This returns an array reference of all the traits which were applied |
1282 | to this attribute. If none were applied, this returns C<undef>. |
88f23977 |
1283 | |
93a708fd |
1284 | =item B<< $attr->has_applied_traits >> |
88f23977 |
1285 | |
93a708fd |
1286 | Returns true if this attribute has any traits applied. |
88f23977 |
1287 | |
c0e30cf5 |
1288 | =back |
1289 | |
1290 | =head1 BUGS |
1291 | |
d4048ef3 |
1292 | See L<Moose/BUGS> for details on reporting bugs. |
c0e30cf5 |
1293 | |
c0e30cf5 |
1294 | =head1 AUTHOR |
1295 | |
1296 | Stevan Little E<lt>stevan@iinteractive.comE<gt> |
1297 | |
98aae381 |
1298 | Yuval Kogman E<lt>nothingmuch@woobling.comE<gt> |
1299 | |
c0e30cf5 |
1300 | =head1 COPYRIGHT AND LICENSE |
1301 | |
7e0492d3 |
1302 | Copyright 2006-2010 by Infinity Interactive, Inc. |
c0e30cf5 |
1303 | |
1304 | L<http://www.iinteractive.com> |
1305 | |
1306 | This library is free software; you can redistribute it and/or modify |
26fbace8 |
1307 | it under the same terms as Perl itself. |
c0e30cf5 |
1308 | |
8a7a9c53 |
1309 | =cut |