Commit | Line | Data |
306290e8 |
1 | package Mouse::Meta::Attribute; |
c3398f5b |
2 | use strict; |
3 | use warnings; |
4 | |
2efc0af1 |
5 | use Carp (); |
6 | use Scalar::Util qw(weaken); |
7 | |
6d28c5cf |
8 | use Mouse::Util; |
9 | |
684db121 |
10 | use Mouse::Meta::TypeConstraint; |
90fe520e |
11 | use Mouse::Meta::Method::Accessor; |
c3398f5b |
12 | |
1b9e472d |
13 | sub BUILDARGS{ |
14 | my $class = shift; |
15 | my $name = shift; |
16 | my %args = (@_ == 1) ? %{$_[0]} : @_; |
17 | |
18 | $args{name} = $name; |
19 | |
20 | # XXX: for backward compatibility (with method modifiers) |
21 | if($class->can('canonicalize_args') != \&canonicalize_args){ |
22 | %args = $class->canonicalize_args($name, %args); |
23 | } |
24 | |
25 | return \%args; |
26 | } |
2efc0af1 |
27 | |
c3398f5b |
28 | sub new { |
1b9e472d |
29 | my $class = shift; |
30 | my $args = $class->BUILDARGS(@_); |
31 | |
32 | my $name = $args->{name}; |
c3398f5b |
33 | |
2efc0af1 |
34 | # taken from Class::MOP::Attribute::new |
35 | |
36 | defined($name) |
37 | or $class->throw_error('You must provide a name for the attribute'); |
2e7e86c6 |
38 | |
1b9e472d |
39 | if(!exists $args->{init_arg}){ |
40 | $args->{init_arg} = $name; |
2efc0af1 |
41 | } |
42 | |
43 | # 'required' requires eigher 'init_arg', 'builder', or 'default' |
1b9e472d |
44 | my $can_be_required = defined( $args->{init_arg} ); |
2efc0af1 |
45 | |
1b9e472d |
46 | if(exists $args->{builder}){ |
121acb8a |
47 | $class->throw_error('builder must be a defined scalar value which is a method name') |
1b9e472d |
48 | if ref $args->{builder} || !(defined $args->{builder}); |
2efc0af1 |
49 | |
50 | $can_be_required++; |
51 | } |
1b9e472d |
52 | elsif(exists $args->{default}){ |
53 | if(ref $args->{default} && ref($args->{default}) ne 'CODE'){ |
2efc0af1 |
54 | $class->throw_error("References are not allowed as default values, you must " |
55 | . "wrap the default of '$name' in a CODE reference (ex: sub { [] } and not [])"); |
56 | } |
57 | $can_be_required++; |
58 | } |
59 | |
1b9e472d |
60 | if( $args->{required} && !$can_be_required ) { |
121acb8a |
61 | $class->throw_error("You cannot have a required attribute ($name) without a default, builder, or an init_arg"); |
2efc0af1 |
62 | } |
63 | |
1b9e472d |
64 | # taken from Mouse::Meta::Attribute->new and _process_args-> |
2efc0af1 |
65 | |
1b9e472d |
66 | if(exists $args->{is}){ |
67 | my $is = $args->{is}; |
2efc0af1 |
68 | |
69 | if($is eq 'ro'){ |
1b9e472d |
70 | $args->{reader} ||= $name; |
2efc0af1 |
71 | } |
72 | elsif($is eq 'rw'){ |
1b9e472d |
73 | if(exists $args->{writer}){ |
74 | $args->{reader} ||= $name; |
2efc0af1 |
75 | } |
76 | else{ |
1b9e472d |
77 | $args->{accessor} ||= $name; |
2efc0af1 |
78 | } |
79 | } |
80 | elsif($is eq 'bare'){ |
81 | # do nothing, but don't complain (later) about missing methods |
82 | } |
83 | else{ |
84 | $is = 'undef' if !defined $is; |
85 | $class->throw_error("I do not understand this option (is => $is) on attribute ($name)"); |
86 | } |
87 | } |
88 | |
89 | my $tc; |
1b9e472d |
90 | if(exists $args->{isa}){ |
91 | $args->{type_constraint} = Mouse::Util::TypeConstraints::find_or_create_isa_type_constraint($args->{isa}); |
2efc0af1 |
92 | } |
1b9e472d |
93 | elsif(exists $args->{does}){ |
94 | $args->{type_constraint} = Mouse::Util::TypeConstraints::find_or_create_does_type_constraint($args->{does}); |
2efc0af1 |
95 | } |
1b9e472d |
96 | $tc = $args->{type_constraint}; |
2efc0af1 |
97 | |
1b9e472d |
98 | if($args->{coerce}){ |
2efc0af1 |
99 | defined($tc) |
100 | || $class->throw_error("You cannot have coercion without specifying a type constraint on attribute ($name)"); |
101 | |
1b9e472d |
102 | $args->{weak_ref} |
121acb8a |
103 | && $class->throw_error("You cannot have a weak reference to a coerced value on attribute ($name)"); |
2efc0af1 |
104 | } |
105 | |
1b9e472d |
106 | if ($args->{lazy_build}) { |
107 | exists($args->{default}) |
121acb8a |
108 | && $class->throw_error("You can not use lazy_build and default for the same attribute ($name)"); |
109 | |
1b9e472d |
110 | $args->{lazy} = 1; |
111 | $args->{builder} ||= "_build_${name}"; |
121acb8a |
112 | if ($name =~ /^_/) { |
1b9e472d |
113 | $args->{clearer} ||= "_clear${name}"; |
114 | $args->{predicate} ||= "_has${name}"; |
121acb8a |
115 | } |
116 | else { |
1b9e472d |
117 | $args->{clearer} ||= "clear_${name}"; |
118 | $args->{predicate} ||= "has_${name}"; |
121acb8a |
119 | } |
2efc0af1 |
120 | } |
121 | |
1b9e472d |
122 | if ($args->{auto_deref}) { |
121acb8a |
123 | defined($tc) |
124 | || $class->throw_error("You cannot auto-dereference without specifying a type constraint on attribute ($name)"); |
2efc0af1 |
125 | |
121acb8a |
126 | ( $tc->is_a_type_of('ArrayRef') || $tc->is_a_type_of('HashRef') ) |
127 | || $class->throw_error("You cannot auto-dereference anything other than a ArrayRef or HashRef on attribute ($name)"); |
2efc0af1 |
128 | } |
129 | |
1b9e472d |
130 | if (exists $args->{trigger}) { |
131 | ('CODE' eq ref $args->{trigger}) |
121acb8a |
132 | || $class->throw_error("Trigger must be a CODE ref on attribute ($name)"); |
2efc0af1 |
133 | } |
45959ffa |
134 | |
1b9e472d |
135 | if ($args->{lazy}) { |
136 | (exists $args->{default} || defined $args->{builder}) |
121acb8a |
137 | || $class->throw_error("You cannot have lazy attribute ($name) without specifying a default value for it"); |
2efc0af1 |
138 | } |
90fe520e |
139 | |
1b9e472d |
140 | my $instance = bless $args, $class; |
2efc0af1 |
141 | |
1b9e472d |
142 | # extra attributes |
143 | if($class ne __PACKAGE__){ |
144 | $class->meta->_initialize_instance($instance, $args); |
90fe520e |
145 | } |
c3398f5b |
146 | |
2efc0af1 |
147 | # XXX: there is no fast way to check attribute validity |
1b9e472d |
148 | # my @bad = ...; |
2efc0af1 |
149 | # if(@bad){ |
150 | # @bad = sort @bad; |
151 | # Carp::cluck("Found unknown argument(s) passed to '$name' attribute constructor in '$class': @bad"); |
152 | # } |
153 | |
1b9e472d |
154 | return $instance |
c3398f5b |
155 | } |
156 | |
1b9e472d |
157 | sub does { |
158 | my ($self, $role_name) = @_; |
159 | my $meta = Mouse::Meta::Class->initialize(ref($self) || $self); |
160 | |
161 | (defined $role_name) |
162 | || $meta->throw_error("You must supply a role name to does()"); |
163 | |
164 | return $meta->does_role($role_name); |
165 | }; |
166 | |
90fe520e |
167 | # readers |
168 | |
f6715552 |
169 | sub name { $_[0]->{name} } |
170 | sub associated_class { $_[0]->{associated_class} } |
90fe520e |
171 | |
172 | sub accessor { $_[0]->{accessor} } |
173 | sub reader { $_[0]->{reader} } |
174 | sub writer { $_[0]->{writer} } |
175 | sub predicate { $_[0]->{predicate} } |
176 | sub clearer { $_[0]->{clearer} } |
177 | sub handles { $_[0]->{handles} } |
178 | |
f6715552 |
179 | sub _is_metadata { $_[0]->{is} } |
180 | sub is_required { $_[0]->{required} } |
181 | sub default { $_[0]->{default} } |
182 | sub is_lazy { $_[0]->{lazy} } |
183 | sub is_lazy_build { $_[0]->{lazy_build} } |
f6715552 |
184 | sub is_weak_ref { $_[0]->{weak_ref} } |
185 | sub init_arg { $_[0]->{init_arg} } |
186 | sub type_constraint { $_[0]->{type_constraint} } |
2efc0af1 |
187 | |
f6715552 |
188 | sub trigger { $_[0]->{trigger} } |
189 | sub builder { $_[0]->{builder} } |
190 | sub should_auto_deref { $_[0]->{auto_deref} } |
2efc0af1 |
191 | sub should_coerce { $_[0]->{coerce} } |
c3398f5b |
192 | |
1b9e472d |
193 | sub get_read_method { $_[0]->{reader} || $_[0]->{accessor} } |
194 | sub get_write_method { $_[0]->{writer} || $_[0]->{accessor} } |
195 | |
90fe520e |
196 | # predicates |
197 | |
198 | sub has_accessor { exists $_[0]->{accessor} } |
199 | sub has_reader { exists $_[0]->{reader} } |
200 | sub has_writer { exists $_[0]->{writer} } |
f6715552 |
201 | sub has_predicate { exists $_[0]->{predicate} } |
202 | sub has_clearer { exists $_[0]->{clearer} } |
203 | sub has_handles { exists $_[0]->{handles} } |
90fe520e |
204 | |
205 | sub has_default { exists $_[0]->{default} } |
f6715552 |
206 | sub has_type_constraint { exists $_[0]->{type_constraint} } |
207 | sub has_trigger { exists $_[0]->{trigger} } |
208 | sub has_builder { exists $_[0]->{builder} } |
eec1bb49 |
209 | |
1b9e472d |
210 | sub has_read_method { exists $_[0]->{reader} || exists $_[0]->{accessor} } |
211 | sub has_write_method { exists $_[0]->{writer} || exists $_[0]->{accessor} } |
212 | |
1bfebf5f |
213 | sub _create_args { |
214 | $_[0]->{_create_args} = $_[1] if @_ > 1; |
215 | $_[0]->{_create_args} |
216 | } |
217 | |
90fe520e |
218 | sub accessor_metaclass { 'Mouse::Meta::Method::Accessor' } |
219 | |
1b9e472d |
220 | sub interpolate_class_and_new{ |
221 | my($class, $name, $args) = @_; |
c3398f5b |
222 | |
1b9e472d |
223 | if(my $metaclass = delete $args->{metaclass}){ |
224 | $class = Mouse::Util::resolve_metaclass_alias( Attribute => $metaclass ); |
225 | } |
1bfebf5f |
226 | |
c3398f5b |
227 | |
1b9e472d |
228 | if(my $traits_ref = delete $args->{traits}){ |
229 | my @traits; |
230 | for (my $i = 0; $i < @{$traits_ref}; $i++) { |
231 | my $trait = Mouse::Util::resolve_metaclass_alias(Attribute => $traits_ref->[$i], trait => 1); |
b2500191 |
232 | |
1b9e472d |
233 | next if $class->does($trait); |
74be9f76 |
234 | |
1b9e472d |
235 | push @traits, $trait; |
236 | |
237 | # are there options? |
238 | push @traits, $traits_ref->[++$i] |
239 | if ref($traits_ref->[$i+1]); |
c3398f5b |
240 | } |
c3398f5b |
241 | |
1b9e472d |
242 | if (@traits) { |
243 | $class = Mouse::Meta::Class->create_anon_class( |
244 | superclasses => [ $class ], |
245 | roles => \@traits, |
246 | cache => 1, |
247 | )->name; |
a7d31de0 |
248 | |
1b9e472d |
249 | $args->{traits} = \@traits; |
250 | } |
74be9f76 |
251 | } |
252 | |
1b9e472d |
253 | return $class->new($name, $args); |
254 | } |
255 | |
256 | sub canonicalize_args{ |
257 | my ($self, $name, %args) = @_; |
258 | |
259 | Carp::cluck("$self->canonicalize_args has been deprecated." |
260 | . "Use \$self->BUILDARGS instead."); |
261 | |
262 | return %args; |
263 | } |
264 | |
265 | sub create { |
266 | my ($self, $class, $name, %args) = @_; |
267 | |
268 | Carp::cluck("$self->create has been deprecated." |
269 | . "Use \$meta->add_attribute and \$attr->install_accessors instead."); |
270 | |
271 | # noop |
272 | return $self; |
c3398f5b |
273 | } |
274 | |
20e25eb9 |
275 | sub verify_against_type_constraint { |
f55f60dd |
276 | my ($self, $value) = @_; |
277 | my $tc = $self->type_constraint; |
278 | return 1 unless $tc; |
5aa30ced |
279 | |
f55f60dd |
280 | local $_ = $value; |
281 | return 1 if $tc->check($value); |
5aa30ced |
282 | |
f55f60dd |
283 | $self->verify_type_constraint_error($self->name, $value, $tc); |
b3b74cc6 |
284 | } |
5aa30ced |
285 | |
b3b74cc6 |
286 | sub verify_type_constraint_error { |
287 | my($self, $name, $value, $type) = @_; |
fce211ae |
288 | $self->throw_error("Attribute ($name) does not pass the type constraint because: " . $type->get_message($value)); |
5aa30ced |
289 | } |
290 | |
8a7f2a8a |
291 | sub coerce_constraint { ## my($self, $value) = @_; |
292 | my $type = $_[0]->{type_constraint} |
293 | or return $_[1]; |
684db121 |
294 | return Mouse::Util::TypeConstraints->typecast_constraints($_[0]->associated_class->name, $_[0]->type_constraint, $_[1]); |
4188b837 |
295 | } |
296 | |
af745d5a |
297 | sub _canonicalize_handles { |
298 | my $self = shift; |
299 | my $handles = shift; |
300 | |
301 | if (ref($handles) eq 'HASH') { |
302 | return %$handles; |
303 | } |
304 | elsif (ref($handles) eq 'ARRAY') { |
305 | return map { $_ => $_ } @$handles; |
306 | } |
307 | else { |
fce211ae |
308 | $self->throw_error("Unable to canonicalize the 'handles' option with $handles"); |
af745d5a |
309 | } |
310 | } |
311 | |
1b9e472d |
312 | sub clone_and_inherit_options{ |
313 | my $self = shift; |
314 | my $name = shift; |
315 | |
316 | return ref($self)->new($name, %{$self}, @_ == 1 ? %{$_[0]} : @_); |
317 | } |
318 | |
1bfebf5f |
319 | sub clone_parent { |
320 | my $self = shift; |
321 | my $class = shift; |
322 | my $name = shift; |
323 | my %args = ($self->get_parent_args($class, $name), @_); |
324 | |
1b9e472d |
325 | Carp::cluck("$self->clone_parent has been deprecated." |
326 | . "Use \$meta->add_attribute and \$attr->install_accessors instead."); |
327 | |
328 | |
1bfebf5f |
329 | $self->create($class, $name, %args); |
330 | } |
331 | |
332 | sub get_parent_args { |
333 | my $self = shift; |
334 | my $class = shift; |
335 | my $name = shift; |
336 | |
724c77c0 |
337 | for my $super ($class->linearized_isa) { |
bb733405 |
338 | my $super_attr = $super->can("meta") && $super->meta->get_attribute($name) |
1bfebf5f |
339 | or next; |
340 | return %{ $super_attr->_create_args }; |
341 | } |
342 | |
fce211ae |
343 | $self->throw_error("Could not find an attribute by the name of '$name' to inherit from"); |
344 | } |
345 | |
1b9e472d |
346 | sub install_accessors{ |
347 | my($attribute) = @_; |
348 | |
349 | my $metaclass = $attribute->{associated_class}; |
350 | my $generator_class = $attribute->accessor_metaclass; |
351 | |
352 | foreach my $type(qw(accessor reader writer predicate clearer handles)){ |
353 | if(exists $attribute->{$type}){ |
354 | my $installer = '_install_' . $type; |
355 | $generator_class->$installer($attribute, $attribute->{$type}, $metaclass); |
356 | $attribute->{associated_methods}++; |
357 | } |
358 | } |
359 | |
360 | if($attribute->can('create') != \&create){ |
361 | $attribute->create($metaclass, $attribute->name, %{$attribute}); |
362 | } |
363 | |
364 | return; |
365 | } |
366 | |
fce211ae |
367 | sub throw_error{ |
368 | my $self = shift; |
369 | |
370 | my $metaclass = (ref $self && $self->associated_class) || 'Mouse::Meta::Class'; |
371 | $metaclass->throw_error(@_, depth => 1); |
1bfebf5f |
372 | } |
373 | |
c3398f5b |
374 | 1; |
375 | |
376 | __END__ |
377 | |
378 | =head1 NAME |
379 | |
306290e8 |
380 | Mouse::Meta::Attribute - attribute metaclass |
c3398f5b |
381 | |
382 | =head1 METHODS |
383 | |
306290e8 |
384 | =head2 new %args -> Mouse::Meta::Attribute |
c3398f5b |
385 | |
306290e8 |
386 | Instantiates a new Mouse::Meta::Attribute. Does nothing else. |
c3398f5b |
387 | |
306290e8 |
388 | =head2 create OwnerClass, AttributeName, %args -> Mouse::Meta::Attribute |
c3398f5b |
389 | |
390 | Creates a new attribute in OwnerClass. Accessors and helper methods are |
391 | installed. Some error checking is done. |
392 | |
393 | =head2 name -> AttributeName |
394 | |
181502b9 |
395 | =head2 associated_class -> OwnerClass |
c3398f5b |
396 | |
ab27a55e |
397 | =head2 is_required -> Bool |
c3398f5b |
398 | |
ab27a55e |
399 | =head2 default -> Item |
c3398f5b |
400 | |
ab27a55e |
401 | =head2 has_default -> Bool |
402 | |
403 | =head2 is_lazy -> Bool |
404 | |
405 | =head2 predicate -> MethodName | Undef |
406 | |
407 | =head2 has_predicate -> Bool |
408 | |
409 | =head2 clearer -> MethodName | Undef |
410 | |
411 | =head2 has_clearer -> Bool |
c3398f5b |
412 | |
413 | =head2 handles -> { LocalName => RemoteName } |
414 | |
ab27a55e |
415 | =head2 has_handles -> Bool |
416 | |
3645b316 |
417 | =head2 is_weak_ref -> Bool |
c3398f5b |
418 | |
419 | =head2 init_arg -> Str |
420 | |
ab27a55e |
421 | =head2 type_constraint -> Str |
422 | |
423 | =head2 has_type_constraint -> Bool |
424 | |
425 | =head2 trigger => CODE | Undef |
426 | |
427 | =head2 has_trigger -> Bool |
428 | |
429 | =head2 builder => MethodName | Undef |
430 | |
431 | =head2 has_builder -> Bool |
432 | |
93f08899 |
433 | =head2 is_lazy_build => Bool |
434 | |
0fff36e6 |
435 | =head2 should_auto_deref -> Bool |
436 | |
c3398f5b |
437 | Informational methods. |
438 | |
20e25eb9 |
439 | =head2 verify_against_type_constraint Item -> 1 | ERROR |
fb706f5c |
440 | |
441 | Checks that the given value passes this attribute's type constraint. Returns 1 |
442 | on success, otherwise C<confess>es. |
443 | |
93d190e0 |
444 | =head2 canonicalize_args Name, %args -> %args |
445 | |
446 | Canonicalizes some arguments to create. In particular, C<lazy_build> is |
447 | canonicalized into C<lazy>, C<builder>, etc. |
448 | |
1bbaa8ed |
449 | =head2 validate_args Name, \%args -> 1 | ERROR |
93d190e0 |
450 | |
451 | Checks that the arguments to create the attribute (ie those specified by |
452 | C<has>) are valid. |
453 | |
f7b11a21 |
454 | =head2 clone_parent OwnerClass, AttributeName, %args -> Mouse::Meta::Attribute |
455 | |
456 | Creates a new attribute in OwnerClass, inheriting options from parent classes. |
457 | Accessors and helper methods are installed. Some error checking is done. |
458 | |
459 | =head2 get_parent_args OwnerClass, AttributeName -> Hash |
460 | |
461 | Returns the options that the parent class of C<OwnerClass> used for attribute |
462 | C<AttributeName>. |
463 | |
c3398f5b |
464 | =cut |
465 | |