Commit | Line | Data |
306290e8 |
1 | package Mouse::Meta::Attribute; |
bc69ee88 |
2 | use Mouse::Util qw(:meta); # enables strict and warnings |
c3398f5b |
3 | |
2efc0af1 |
4 | use Carp (); |
2efc0af1 |
5 | |
684db121 |
6 | use Mouse::Meta::TypeConstraint; |
d7d8d49b |
7 | |
8 | #use Mouse::Meta::Method::Accessor; |
9 | use Mouse::Meta::Method::Delegation; |
c3398f5b |
10 | |
87ca293b |
11 | sub _process_options{ |
12 | my($class, $name, $args) = @_; |
c3398f5b |
13 | |
04493075 |
14 | |
15 | # XXX: for backward compatibility (with method modifiers) |
16 | if($class->can('canonicalize_args') != \&canonicalize_args){ |
17 | %{$args} = $class->canonicalize_args($name, %{$args}); |
18 | } |
19 | |
2efc0af1 |
20 | # taken from Class::MOP::Attribute::new |
21 | |
22 | defined($name) |
23 | or $class->throw_error('You must provide a name for the attribute'); |
2e7e86c6 |
24 | |
1b9e472d |
25 | if(!exists $args->{init_arg}){ |
26 | $args->{init_arg} = $name; |
2efc0af1 |
27 | } |
28 | |
29 | # 'required' requires eigher 'init_arg', 'builder', or 'default' |
1b9e472d |
30 | my $can_be_required = defined( $args->{init_arg} ); |
2efc0af1 |
31 | |
1b9e472d |
32 | if(exists $args->{builder}){ |
c6d8f5ca |
33 | # XXX: |
34 | # Moose refuses a CODE ref builder, but Mouse doesn't for backward compatibility |
35 | # This feature will be changed in a future. (gfx) |
121acb8a |
36 | $class->throw_error('builder must be a defined scalar value which is a method name') |
c6d8f5ca |
37 | #if ref $args->{builder} || !defined $args->{builder}; |
38 | if !defined $args->{builder}; |
2efc0af1 |
39 | |
40 | $can_be_required++; |
41 | } |
1b9e472d |
42 | elsif(exists $args->{default}){ |
43 | if(ref $args->{default} && ref($args->{default}) ne 'CODE'){ |
2efc0af1 |
44 | $class->throw_error("References are not allowed as default values, you must " |
45 | . "wrap the default of '$name' in a CODE reference (ex: sub { [] } and not [])"); |
46 | } |
47 | $can_be_required++; |
48 | } |
49 | |
1b9e472d |
50 | if( $args->{required} && !$can_be_required ) { |
121acb8a |
51 | $class->throw_error("You cannot have a required attribute ($name) without a default, builder, or an init_arg"); |
2efc0af1 |
52 | } |
53 | |
1b9e472d |
54 | # taken from Mouse::Meta::Attribute->new and _process_args-> |
2efc0af1 |
55 | |
1b9e472d |
56 | if(exists $args->{is}){ |
57 | my $is = $args->{is}; |
2efc0af1 |
58 | |
59 | if($is eq 'ro'){ |
1b9e472d |
60 | $args->{reader} ||= $name; |
2efc0af1 |
61 | } |
62 | elsif($is eq 'rw'){ |
1b9e472d |
63 | if(exists $args->{writer}){ |
64 | $args->{reader} ||= $name; |
2efc0af1 |
65 | } |
66 | else{ |
1b9e472d |
67 | $args->{accessor} ||= $name; |
2efc0af1 |
68 | } |
69 | } |
70 | elsif($is eq 'bare'){ |
71 | # do nothing, but don't complain (later) about missing methods |
72 | } |
73 | else{ |
74 | $is = 'undef' if !defined $is; |
75 | $class->throw_error("I do not understand this option (is => $is) on attribute ($name)"); |
76 | } |
77 | } |
78 | |
79 | my $tc; |
1b9e472d |
80 | if(exists $args->{isa}){ |
81 | $args->{type_constraint} = Mouse::Util::TypeConstraints::find_or_create_isa_type_constraint($args->{isa}); |
2efc0af1 |
82 | } |
1b9e472d |
83 | elsif(exists $args->{does}){ |
9f74c401 |
84 | $args->{type_constraint} = Mouse::Util::TypeConstraints::find_or_create_does_type_constraint($args->{does}); |
2efc0af1 |
85 | } |
1b9e472d |
86 | $tc = $args->{type_constraint}; |
2efc0af1 |
87 | |
1b9e472d |
88 | if($args->{coerce}){ |
2efc0af1 |
89 | defined($tc) |
90 | || $class->throw_error("You cannot have coercion without specifying a type constraint on attribute ($name)"); |
91 | |
1b9e472d |
92 | $args->{weak_ref} |
121acb8a |
93 | && $class->throw_error("You cannot have a weak reference to a coerced value on attribute ($name)"); |
2efc0af1 |
94 | } |
95 | |
1b9e472d |
96 | if ($args->{lazy_build}) { |
97 | exists($args->{default}) |
121acb8a |
98 | && $class->throw_error("You can not use lazy_build and default for the same attribute ($name)"); |
99 | |
1b9e472d |
100 | $args->{lazy} = 1; |
101 | $args->{builder} ||= "_build_${name}"; |
121acb8a |
102 | if ($name =~ /^_/) { |
1b9e472d |
103 | $args->{clearer} ||= "_clear${name}"; |
104 | $args->{predicate} ||= "_has${name}"; |
121acb8a |
105 | } |
106 | else { |
1b9e472d |
107 | $args->{clearer} ||= "clear_${name}"; |
108 | $args->{predicate} ||= "has_${name}"; |
121acb8a |
109 | } |
2efc0af1 |
110 | } |
111 | |
1b9e472d |
112 | if ($args->{auto_deref}) { |
121acb8a |
113 | defined($tc) |
114 | || $class->throw_error("You cannot auto-dereference without specifying a type constraint on attribute ($name)"); |
2efc0af1 |
115 | |
121acb8a |
116 | ( $tc->is_a_type_of('ArrayRef') || $tc->is_a_type_of('HashRef') ) |
117 | || $class->throw_error("You cannot auto-dereference anything other than a ArrayRef or HashRef on attribute ($name)"); |
2efc0af1 |
118 | } |
119 | |
1b9e472d |
120 | if (exists $args->{trigger}) { |
121 | ('CODE' eq ref $args->{trigger}) |
121acb8a |
122 | || $class->throw_error("Trigger must be a CODE ref on attribute ($name)"); |
2efc0af1 |
123 | } |
45959ffa |
124 | |
1b9e472d |
125 | if ($args->{lazy}) { |
126 | (exists $args->{default} || defined $args->{builder}) |
121acb8a |
127 | || $class->throw_error("You cannot have lazy attribute ($name) without specifying a default value for it"); |
2efc0af1 |
128 | } |
90fe520e |
129 | |
87ca293b |
130 | return; |
131 | } |
132 | |
133 | sub new { |
134 | my $class = shift; |
135 | my $name = shift; |
136 | |
137 | my %args = (@_ == 1) ? %{ $_[0] } : @_; |
138 | |
139 | $class->_process_options($name, \%args); |
140 | |
141 | $args{name} = $name; |
142 | |
926290ac |
143 | my $self = bless \%args, $class; |
2efc0af1 |
144 | |
1b9e472d |
145 | # extra attributes |
146 | if($class ne __PACKAGE__){ |
926290ac |
147 | $class->meta->_initialize_object($self, \%args); |
90fe520e |
148 | } |
c3398f5b |
149 | |
2efc0af1 |
150 | # XXX: there is no fast way to check attribute validity |
1b9e472d |
151 | # my @bad = ...; |
2efc0af1 |
152 | # if(@bad){ |
153 | # @bad = sort @bad; |
154 | # Carp::cluck("Found unknown argument(s) passed to '$name' attribute constructor in '$class': @bad"); |
155 | # } |
156 | |
926290ac |
157 | return $self; |
c3398f5b |
158 | } |
159 | |
43165725 |
160 | sub has_read_method { $_[0]->has_reader || $_[0]->has_accessor } |
161 | sub has_write_method { $_[0]->has_writer || $_[0]->has_accessor } |
1b9e472d |
162 | |
df77fd72 |
163 | sub _create_args { # DEPRECATED |
1bfebf5f |
164 | $_[0]->{_create_args} = $_[1] if @_ > 1; |
165 | $_[0]->{_create_args} |
166 | } |
167 | |
87ca293b |
168 | sub interpolate_class{ |
8cf51b82 |
169 | my($class, $args) = @_; |
c3398f5b |
170 | |
1b9e472d |
171 | if(my $metaclass = delete $args->{metaclass}){ |
172 | $class = Mouse::Util::resolve_metaclass_alias( Attribute => $metaclass ); |
173 | } |
1bfebf5f |
174 | |
87ca293b |
175 | my @traits; |
1b9e472d |
176 | if(my $traits_ref = delete $args->{traits}){ |
87ca293b |
177 | |
f3f04eed |
178 | for (my $i = 0; $i < @{$traits_ref}; $i++) { |
179 | my $trait = Mouse::Util::resolve_metaclass_alias(Attribute => $traits_ref->[$i], trait => 1); |
b2500191 |
180 | |
f3f04eed |
181 | next if $class->does($trait); |
74be9f76 |
182 | |
f3f04eed |
183 | push @traits, $trait; |
1b9e472d |
184 | |
f3f04eed |
185 | # are there options? |
186 | push @traits, $traits_ref->[++$i] |
187 | if ref($traits_ref->[$i+1]); |
188 | } |
c3398f5b |
189 | |
1b9e472d |
190 | if (@traits) { |
191 | $class = Mouse::Meta::Class->create_anon_class( |
192 | superclasses => [ $class ], |
193 | roles => \@traits, |
194 | cache => 1, |
195 | )->name; |
1b9e472d |
196 | } |
74be9f76 |
197 | } |
198 | |
87ca293b |
199 | return( $class, @traits ); |
1b9e472d |
200 | } |
201 | |
df77fd72 |
202 | sub canonicalize_args{ # DEPRECATED |
1b9e472d |
203 | my ($self, $name, %args) = @_; |
204 | |
205 | Carp::cluck("$self->canonicalize_args has been deprecated." |
04493075 |
206 | . "Use \$self->_process_options instead.") |
8aba926d |
207 | if Mouse::Util::_MOUSE_VERBOSE; |
1b9e472d |
208 | |
209 | return %args; |
210 | } |
211 | |
ce5920b7 |
212 | sub create { # DEPRECATED |
1b9e472d |
213 | my ($self, $class, $name, %args) = @_; |
214 | |
215 | Carp::cluck("$self->create has been deprecated." |
04493075 |
216 | . "Use \$meta->add_attribute and \$attr->install_accessors instead.") |
8aba926d |
217 | if Mouse::Util::_MOUSE_VERBOSE; |
1b9e472d |
218 | |
219 | # noop |
220 | return $self; |
c3398f5b |
221 | } |
222 | |
ffbbf459 |
223 | sub _coerce_and_verify { |
224 | my($self, $value, $instance) = @_; |
225 | |
226 | my $type_constraint = $self->{type_constraint}; |
4331a3f9 |
227 | return $value if !defined $type_constraint; |
ffbbf459 |
228 | |
229 | if ($self->should_coerce && $type_constraint->has_coercion) { |
230 | $value = $type_constraint->coerce($value); |
231 | } |
232 | |
ffbbf459 |
233 | $self->verify_against_type_constraint($value); |
234 | |
235 | return $value; |
236 | } |
237 | |
20e25eb9 |
238 | sub verify_against_type_constraint { |
f55f60dd |
239 | my ($self, $value) = @_; |
5aa30ced |
240 | |
ffbbf459 |
241 | my $type_constraint = $self->{type_constraint}; |
4331a3f9 |
242 | return 1 if !$type_constraint; |
ffbbf459 |
243 | return 1 if $type_constraint->check($value); |
5aa30ced |
244 | |
ffbbf459 |
245 | $self->verify_type_constraint_error($self->name, $value, $type_constraint); |
b3b74cc6 |
246 | } |
5aa30ced |
247 | |
b3b74cc6 |
248 | sub verify_type_constraint_error { |
249 | my($self, $name, $value, $type) = @_; |
4331a3f9 |
250 | $self->throw_error("Attribute ($name) does not pass the type constraint because: " |
251 | . $type->get_message($value)); |
5aa30ced |
252 | } |
253 | |
df77fd72 |
254 | sub coerce_constraint { # DEPRECATED |
8a7f2a8a |
255 | my $type = $_[0]->{type_constraint} |
256 | or return $_[1]; |
e763d56e |
257 | |
258 | Carp::cluck("coerce_constraint() has been deprecated, which was an internal utility anyway"); |
259 | |
7ca5c5fb |
260 | return Mouse::Util::TypeConstraints->typecast_constraints($_[0]->associated_class->name, $type, $_[1]); |
4188b837 |
261 | } |
262 | |
1b9e472d |
263 | sub clone_and_inherit_options{ |
8cf51b82 |
264 | my($self, %args) = @_; |
265 | |
266 | my($attribute_class, @traits) = ref($self)->interpolate_class(\%args); |
1b9e472d |
267 | |
8cf51b82 |
268 | $args{traits} = \@traits if @traits; |
4f41d79b |
269 | # do not inherit the 'handles' attribute |
270 | foreach my $name(keys %{$self}){ |
271 | if(!exists $args{$name} && $name ne 'handles'){ |
272 | $args{$name} = $self->{$name}; |
273 | } |
274 | } |
275 | return $attribute_class->new($self->name, %args); |
1b9e472d |
276 | } |
277 | |
df77fd72 |
278 | sub clone_parent { # DEPRECATED |
1bfebf5f |
279 | my $self = shift; |
280 | my $class = shift; |
281 | my $name = shift; |
282 | my %args = ($self->get_parent_args($class, $name), @_); |
283 | |
1b9e472d |
284 | Carp::cluck("$self->clone_parent has been deprecated." |
04493075 |
285 | . "Use \$meta->add_attribute and \$attr->install_accessors instead.") |
8aba926d |
286 | if Mouse::Util::_MOUSE_VERBOSE; |
1b9e472d |
287 | |
7ca5c5fb |
288 | $self->clone_and_inherited_args($class, $name, %args); |
1bfebf5f |
289 | } |
290 | |
df77fd72 |
291 | sub get_parent_args { # DEPRECATED |
1bfebf5f |
292 | my $self = shift; |
293 | my $class = shift; |
294 | my $name = shift; |
295 | |
724c77c0 |
296 | for my $super ($class->linearized_isa) { |
bb733405 |
297 | my $super_attr = $super->can("meta") && $super->meta->get_attribute($name) |
1bfebf5f |
298 | or next; |
299 | return %{ $super_attr->_create_args }; |
300 | } |
301 | |
fce211ae |
302 | $self->throw_error("Could not find an attribute by the name of '$name' to inherit from"); |
303 | } |
304 | |
2a464664 |
305 | |
0126c27c |
306 | sub get_read_method { |
43165725 |
307 | $_[0]->reader || $_[0]->accessor |
df77fd72 |
308 | } |
0126c27c |
309 | sub get_write_method { |
43165725 |
310 | $_[0]->writer || $_[0]->accessor |
df77fd72 |
311 | } |
2a464664 |
312 | |
313 | sub get_read_method_ref{ |
314 | my($self) = @_; |
315 | |
316 | $self->{_read_method_ref} ||= do{ |
317 | my $metaclass = $self->associated_class |
318 | or $self->throw_error('No asocciated class for ' . $self->name); |
319 | |
320 | my $reader = $self->{reader} || $self->{accessor}; |
321 | if($reader){ |
322 | $metaclass->name->can($reader); |
323 | } |
324 | else{ |
4ab51fb0 |
325 | $self->accessor_metaclass->_generate_reader($self, $metaclass); |
2a464664 |
326 | } |
327 | }; |
328 | } |
329 | |
330 | sub get_write_method_ref{ |
331 | my($self) = @_; |
332 | |
333 | $self->{_write_method_ref} ||= do{ |
334 | my $metaclass = $self->associated_class |
335 | or $self->throw_error('No asocciated class for ' . $self->name); |
336 | |
337 | my $reader = $self->{writer} || $self->{accessor}; |
338 | if($reader){ |
339 | $metaclass->name->can($reader); |
340 | } |
341 | else{ |
4ab51fb0 |
342 | $self->accessor_metaclass->_generate_writer($self, $metaclass); |
2a464664 |
343 | } |
344 | }; |
345 | } |
346 | |
4ab51fb0 |
347 | sub _canonicalize_handles { |
348 | my($self, $handles) = @_; |
349 | |
350 | if (ref($handles) eq 'HASH') { |
351 | return %$handles; |
352 | } |
353 | elsif (ref($handles) eq 'ARRAY') { |
354 | return map { $_ => $_ } @$handles; |
355 | } |
9ae9702e |
356 | elsif (ref($handles) eq 'Regexp') { |
357 | my $class_or_role = ($self->{isa} || $self->{does}) |
358 | || $self->throw_error("Cannot delegate methods based on a Regexp without a type constraint (isa)"); |
359 | |
360 | my $meta = Mouse::Meta::Class->initialize("$class_or_role"); # "" for stringify |
361 | return map { $_ => $_ } |
007481ba |
362 | grep { !Mouse::Object->can($_) && $_ =~ $handles } |
f48920c1 |
363 | Mouse::Util::is_a_metarole($meta) |
745220df |
364 | ? $meta->get_method_list |
365 | : $meta->get_all_method_names; |
9ae9702e |
366 | } |
4ab51fb0 |
367 | else { |
368 | $self->throw_error("Unable to canonicalize the 'handles' option with $handles"); |
369 | } |
370 | } |
371 | |
04493075 |
372 | sub associate_method{ |
e5e22afd |
373 | my ($attribute, $method_name) = @_; |
04493075 |
374 | $attribute->{associated_methods}++; |
375 | return; |
376 | } |
377 | |
d7d8d49b |
378 | sub delegation_metaclass() { 'Mouse::Meta::Method::Delegation' } |
379 | |
1b9e472d |
380 | sub install_accessors{ |
381 | my($attribute) = @_; |
382 | |
93540011 |
383 | my $metaclass = $attribute->associated_class; |
4ab51fb0 |
384 | my $accessor_class = $attribute->accessor_metaclass; |
1b9e472d |
385 | |
4ab51fb0 |
386 | foreach my $type(qw(accessor reader writer predicate clearer)){ |
1b9e472d |
387 | if(exists $attribute->{$type}){ |
4ab51fb0 |
388 | my $generator = '_generate_' . $type; |
389 | my $code = $accessor_class->$generator($attribute, $metaclass); |
390 | $metaclass->add_method($attribute->{$type} => $code); |
e5e22afd |
391 | $attribute->associate_method($attribute->{$type}); |
4ab51fb0 |
392 | } |
393 | } |
7ca5c5fb |
394 | |
4ab51fb0 |
395 | # install delegation |
396 | if(exists $attribute->{handles}){ |
d7d8d49b |
397 | my $delegation_class = $attribute->delegation_metaclass; |
4ab51fb0 |
398 | my %handles = $attribute->_canonicalize_handles($attribute->{handles}); |
399 | my $reader = $attribute->get_read_method_ref; |
7ca5c5fb |
400 | |
4ab51fb0 |
401 | while(my($handle_name, $method_to_call) = each %handles){ |
d7d8d49b |
402 | my $code = $delegation_class->_generate_delegation($attribute, $metaclass, |
4ab51fb0 |
403 | $reader, $handle_name, $method_to_call); |
404 | |
405 | $metaclass->add_method($handle_name => $code); |
e5e22afd |
406 | $attribute->associate_method($handle_name); |
1b9e472d |
407 | } |
408 | } |
409 | |
410 | if($attribute->can('create') != \&create){ |
7ca5c5fb |
411 | # backword compatibility |
1b9e472d |
412 | $attribute->create($metaclass, $attribute->name, %{$attribute}); |
413 | } |
414 | |
415 | return; |
416 | } |
417 | |
fce211ae |
418 | sub throw_error{ |
419 | my $self = shift; |
420 | |
421 | my $metaclass = (ref $self && $self->associated_class) || 'Mouse::Meta::Class'; |
422 | $metaclass->throw_error(@_, depth => 1); |
1bfebf5f |
423 | } |
424 | |
c3398f5b |
425 | 1; |
c3398f5b |
426 | __END__ |
427 | |
428 | =head1 NAME |
429 | |
bedd575c |
430 | Mouse::Meta::Attribute - The Mouse attribute metaclass |
c3398f5b |
431 | |
a25ca8d6 |
432 | =head1 VERSION |
433 | |
5176a3e4 |
434 | This document describes Mouse version 0.42 |
a25ca8d6 |
435 | |
c3398f5b |
436 | =head1 METHODS |
437 | |
1820fffe |
438 | =head2 C<< new(%options) -> Mouse::Meta::Attribute >> |
c3398f5b |
439 | |
306290e8 |
440 | Instantiates a new Mouse::Meta::Attribute. Does nothing else. |
c3398f5b |
441 | |
1820fffe |
442 | It adds the following options to the constructor: |
c3398f5b |
443 | |
1820fffe |
444 | =over 4 |
c3398f5b |
445 | |
612d3e1a |
446 | =item C<< is => 'ro', 'rw', 'bare' >> |
c3398f5b |
447 | |
1820fffe |
448 | This provides a shorthand for specifying the C<reader>, C<writer>, or |
449 | C<accessor> names. If the attribute is read-only ('ro') then it will |
450 | have a C<reader> method with the same attribute as the name. |
c3398f5b |
451 | |
1820fffe |
452 | If it is read-write ('rw') then it will have an C<accessor> method |
453 | with the same name. If you provide an explicit C<writer> for a |
454 | read-write attribute, then you will have a C<reader> with the same |
455 | name as the attribute, and a C<writer> with the name you provided. |
c3398f5b |
456 | |
1820fffe |
457 | Use 'bare' when you are deliberately not installing any methods |
458 | (accessor, reader, etc.) associated with this attribute; otherwise, |
459 | Moose will issue a deprecation warning when this attribute is added to a |
460 | metaclass. |
c3398f5b |
461 | |
612d3e1a |
462 | =item C<< isa => Type >> |
ab27a55e |
463 | |
1820fffe |
464 | This option accepts a type. The type can be a string, which should be |
465 | a type name. If the type name is unknown, it is assumed to be a class |
466 | name. |
ab27a55e |
467 | |
1820fffe |
468 | This option can also accept a L<Moose::Meta::TypeConstraint> object. |
ab27a55e |
469 | |
1820fffe |
470 | If you I<also> provide a C<does> option, then your C<isa> option must |
471 | be a class name, and that class must do the role specified with |
472 | C<does>. |
ab27a55e |
473 | |
612d3e1a |
474 | =item C<< does => Role >> |
ab27a55e |
475 | |
1820fffe |
476 | This is short-hand for saying that the attribute's type must be an |
477 | object which does the named role. |
c3398f5b |
478 | |
1820fffe |
479 | B<This option is not yet supported.> |
c3398f5b |
480 | |
612d3e1a |
481 | =item C<< coerce => Bool >> |
ab27a55e |
482 | |
1820fffe |
483 | This option is only valid for objects with a type constraint |
484 | (C<isa>). If this is true, then coercions will be applied whenever |
485 | this attribute is set. |
c3398f5b |
486 | |
1820fffe |
487 | You can make both this and the C<weak_ref> option true. |
c3398f5b |
488 | |
612d3e1a |
489 | =item C<< trigger => CodeRef >> |
ab27a55e |
490 | |
1820fffe |
491 | This option accepts a subroutine reference, which will be called after |
492 | the attribute is set. |
ab27a55e |
493 | |
612d3e1a |
494 | =item C<< required => Bool >> |
ab27a55e |
495 | |
1820fffe |
496 | An attribute which is required must be provided to the constructor. An |
497 | attribute which is required can also have a C<default> or C<builder>, |
498 | which will satisfy its required-ness. |
ab27a55e |
499 | |
1820fffe |
500 | A required attribute must have a C<default>, C<builder> or a |
501 | non-C<undef> C<init_arg> |
ab27a55e |
502 | |
612d3e1a |
503 | =item C<< lazy => Bool >> |
ab27a55e |
504 | |
1820fffe |
505 | A lazy attribute must have a C<default> or C<builder>. When an |
506 | attribute is lazy, the default value will not be calculated until the |
507 | attribute is read. |
93f08899 |
508 | |
612d3e1a |
509 | =item C<< weak_ref => Bool >> |
0fff36e6 |
510 | |
1820fffe |
511 | If this is true, the attribute's value will be stored as a weak |
512 | reference. |
c3398f5b |
513 | |
612d3e1a |
514 | =item C<< auto_deref => Bool >> |
fb706f5c |
515 | |
1820fffe |
516 | If this is true, then the reader will dereference the value when it is |
517 | called. The attribute must have a type constraint which defines the |
518 | attribute as an array or hash reference. |
519 | |
612d3e1a |
520 | =item C<< lazy_build => Bool >> |
1820fffe |
521 | |
522 | Setting this to true makes the attribute lazy and provides a number of |
523 | default methods. |
fb706f5c |
524 | |
1820fffe |
525 | has 'size' => ( |
526 | is => 'ro', |
527 | lazy_build => 1, |
528 | ); |
93d190e0 |
529 | |
1820fffe |
530 | is equivalent to this: |
93d190e0 |
531 | |
1820fffe |
532 | has 'size' => ( |
533 | is => 'ro', |
534 | lazy => 1, |
535 | builder => '_build_size', |
536 | clearer => 'clear_size', |
537 | predicate => 'has_size', |
538 | ); |
93d190e0 |
539 | |
1820fffe |
540 | =back |
541 | |
e5e22afd |
542 | =head2 C<< associate_method(MethodName) >> |
31c5194b |
543 | |
544 | Associates a method with the attribute. Typically, this is called internally |
545 | when an attribute generates its accessors. |
546 | |
e5e22afd |
547 | Currently the argument I<MethodName> is ignored in Mouse. |
31c5194b |
548 | |
1820fffe |
549 | =head2 C<< verify_against_type_constraint(Item) -> TRUE | ERROR >> |
550 | |
551 | Checks that the given value passes this attribute's type constraint. Returns C<true> |
552 | on success, otherwise C<confess>es. |
93d190e0 |
553 | |
1820fffe |
554 | =head2 C<< clone_and_inherit_options(options) -> Mouse::Meta::Attribute >> |
f7b11a21 |
555 | |
612d3e1a |
556 | Creates a new attribute in the owner class, inheriting options from parent classes. |
f7b11a21 |
557 | Accessors and helper methods are installed. Some error checking is done. |
558 | |
9ae9702e |
559 | =head2 C<< get_read_method_ref >> |
560 | |
561 | =head2 C<< get_write_method_ref >> |
562 | |
563 | Returns the subroutine reference of a method suitable for reading or |
564 | writing the attribute's value in the associated class. These methods |
565 | always return a subroutine reference, regardless of whether or not the |
df77fd72 |
566 | attribute is read- or write-only. |
567 | |
1820fffe |
568 | =head1 SEE ALSO |
f7b11a21 |
569 | |
1820fffe |
570 | L<Moose::Meta::Attribute> |
f7b11a21 |
571 | |
31c5194b |
572 | L<Class::MOP::Attribute> |
573 | |
c3398f5b |
574 | =cut |
575 | |