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 | |
53875581 |
8 | use Mouse::Util qw(:meta); |
6d28c5cf |
9 | |
684db121 |
10 | use Mouse::Meta::TypeConstraint; |
90fe520e |
11 | use Mouse::Meta::Method::Accessor; |
c3398f5b |
12 | |
87ca293b |
13 | sub _process_options{ |
14 | my($class, $name, $args) = @_; |
c3398f5b |
15 | |
2efc0af1 |
16 | # taken from Class::MOP::Attribute::new |
17 | |
18 | defined($name) |
19 | or $class->throw_error('You must provide a name for the attribute'); |
2e7e86c6 |
20 | |
1b9e472d |
21 | if(!exists $args->{init_arg}){ |
22 | $args->{init_arg} = $name; |
2efc0af1 |
23 | } |
24 | |
25 | # 'required' requires eigher 'init_arg', 'builder', or 'default' |
1b9e472d |
26 | my $can_be_required = defined( $args->{init_arg} ); |
2efc0af1 |
27 | |
1b9e472d |
28 | if(exists $args->{builder}){ |
121acb8a |
29 | $class->throw_error('builder must be a defined scalar value which is a method name') |
1b9e472d |
30 | if ref $args->{builder} || !(defined $args->{builder}); |
2efc0af1 |
31 | |
32 | $can_be_required++; |
33 | } |
1b9e472d |
34 | elsif(exists $args->{default}){ |
35 | if(ref $args->{default} && ref($args->{default}) ne 'CODE'){ |
2efc0af1 |
36 | $class->throw_error("References are not allowed as default values, you must " |
37 | . "wrap the default of '$name' in a CODE reference (ex: sub { [] } and not [])"); |
38 | } |
39 | $can_be_required++; |
40 | } |
41 | |
1b9e472d |
42 | if( $args->{required} && !$can_be_required ) { |
121acb8a |
43 | $class->throw_error("You cannot have a required attribute ($name) without a default, builder, or an init_arg"); |
2efc0af1 |
44 | } |
45 | |
1b9e472d |
46 | # taken from Mouse::Meta::Attribute->new and _process_args-> |
2efc0af1 |
47 | |
1b9e472d |
48 | if(exists $args->{is}){ |
49 | my $is = $args->{is}; |
2efc0af1 |
50 | |
51 | if($is eq 'ro'){ |
1b9e472d |
52 | $args->{reader} ||= $name; |
2efc0af1 |
53 | } |
54 | elsif($is eq 'rw'){ |
1b9e472d |
55 | if(exists $args->{writer}){ |
56 | $args->{reader} ||= $name; |
2efc0af1 |
57 | } |
58 | else{ |
1b9e472d |
59 | $args->{accessor} ||= $name; |
2efc0af1 |
60 | } |
61 | } |
62 | elsif($is eq 'bare'){ |
63 | # do nothing, but don't complain (later) about missing methods |
64 | } |
65 | else{ |
66 | $is = 'undef' if !defined $is; |
67 | $class->throw_error("I do not understand this option (is => $is) on attribute ($name)"); |
68 | } |
69 | } |
70 | |
71 | my $tc; |
1b9e472d |
72 | if(exists $args->{isa}){ |
73 | $args->{type_constraint} = Mouse::Util::TypeConstraints::find_or_create_isa_type_constraint($args->{isa}); |
2efc0af1 |
74 | } |
1b9e472d |
75 | elsif(exists $args->{does}){ |
76 | $args->{type_constraint} = Mouse::Util::TypeConstraints::find_or_create_does_type_constraint($args->{does}); |
2efc0af1 |
77 | } |
1b9e472d |
78 | $tc = $args->{type_constraint}; |
2efc0af1 |
79 | |
1b9e472d |
80 | if($args->{coerce}){ |
2efc0af1 |
81 | defined($tc) |
82 | || $class->throw_error("You cannot have coercion without specifying a type constraint on attribute ($name)"); |
83 | |
1b9e472d |
84 | $args->{weak_ref} |
121acb8a |
85 | && $class->throw_error("You cannot have a weak reference to a coerced value on attribute ($name)"); |
2efc0af1 |
86 | } |
87 | |
1b9e472d |
88 | if ($args->{lazy_build}) { |
89 | exists($args->{default}) |
121acb8a |
90 | && $class->throw_error("You can not use lazy_build and default for the same attribute ($name)"); |
91 | |
1b9e472d |
92 | $args->{lazy} = 1; |
93 | $args->{builder} ||= "_build_${name}"; |
121acb8a |
94 | if ($name =~ /^_/) { |
1b9e472d |
95 | $args->{clearer} ||= "_clear${name}"; |
96 | $args->{predicate} ||= "_has${name}"; |
121acb8a |
97 | } |
98 | else { |
1b9e472d |
99 | $args->{clearer} ||= "clear_${name}"; |
100 | $args->{predicate} ||= "has_${name}"; |
121acb8a |
101 | } |
2efc0af1 |
102 | } |
103 | |
1b9e472d |
104 | if ($args->{auto_deref}) { |
121acb8a |
105 | defined($tc) |
106 | || $class->throw_error("You cannot auto-dereference without specifying a type constraint on attribute ($name)"); |
2efc0af1 |
107 | |
121acb8a |
108 | ( $tc->is_a_type_of('ArrayRef') || $tc->is_a_type_of('HashRef') ) |
109 | || $class->throw_error("You cannot auto-dereference anything other than a ArrayRef or HashRef on attribute ($name)"); |
2efc0af1 |
110 | } |
111 | |
1b9e472d |
112 | if (exists $args->{trigger}) { |
113 | ('CODE' eq ref $args->{trigger}) |
121acb8a |
114 | || $class->throw_error("Trigger must be a CODE ref on attribute ($name)"); |
2efc0af1 |
115 | } |
45959ffa |
116 | |
1b9e472d |
117 | if ($args->{lazy}) { |
118 | (exists $args->{default} || defined $args->{builder}) |
121acb8a |
119 | || $class->throw_error("You cannot have lazy attribute ($name) without specifying a default value for it"); |
2efc0af1 |
120 | } |
90fe520e |
121 | |
87ca293b |
122 | # XXX: for backward compatibility (with method modifiers) |
123 | if($class->can('canonicalize_args') != \&canonicalize_args){ |
124 | %{$args} = $class->canonicalize_args($name, %{$args}); |
125 | } |
126 | return; |
127 | } |
128 | |
129 | sub new { |
130 | my $class = shift; |
131 | my $name = shift; |
132 | |
133 | my %args = (@_ == 1) ? %{ $_[0] } : @_; |
134 | |
135 | $class->_process_options($name, \%args); |
136 | |
137 | $args{name} = $name; |
138 | |
139 | my $instance = bless \%args, $class; |
2efc0af1 |
140 | |
1b9e472d |
141 | # extra attributes |
142 | if($class ne __PACKAGE__){ |
87ca293b |
143 | $class->meta->_initialize_instance($instance,\%args); |
90fe520e |
144 | } |
c3398f5b |
145 | |
2efc0af1 |
146 | # XXX: there is no fast way to check attribute validity |
1b9e472d |
147 | # my @bad = ...; |
2efc0af1 |
148 | # if(@bad){ |
149 | # @bad = sort @bad; |
150 | # Carp::cluck("Found unknown argument(s) passed to '$name' attribute constructor in '$class': @bad"); |
151 | # } |
152 | |
1b9e472d |
153 | return $instance |
c3398f5b |
154 | } |
155 | |
90fe520e |
156 | # readers |
157 | |
f6715552 |
158 | sub name { $_[0]->{name} } |
159 | sub associated_class { $_[0]->{associated_class} } |
90fe520e |
160 | |
161 | sub accessor { $_[0]->{accessor} } |
162 | sub reader { $_[0]->{reader} } |
163 | sub writer { $_[0]->{writer} } |
164 | sub predicate { $_[0]->{predicate} } |
165 | sub clearer { $_[0]->{clearer} } |
166 | sub handles { $_[0]->{handles} } |
167 | |
f6715552 |
168 | sub _is_metadata { $_[0]->{is} } |
169 | sub is_required { $_[0]->{required} } |
170 | sub default { $_[0]->{default} } |
171 | sub is_lazy { $_[0]->{lazy} } |
172 | sub is_lazy_build { $_[0]->{lazy_build} } |
f6715552 |
173 | sub is_weak_ref { $_[0]->{weak_ref} } |
174 | sub init_arg { $_[0]->{init_arg} } |
175 | sub type_constraint { $_[0]->{type_constraint} } |
2efc0af1 |
176 | |
f6715552 |
177 | sub trigger { $_[0]->{trigger} } |
178 | sub builder { $_[0]->{builder} } |
179 | sub should_auto_deref { $_[0]->{auto_deref} } |
2efc0af1 |
180 | sub should_coerce { $_[0]->{coerce} } |
c3398f5b |
181 | |
1b9e472d |
182 | sub get_read_method { $_[0]->{reader} || $_[0]->{accessor} } |
183 | sub get_write_method { $_[0]->{writer} || $_[0]->{accessor} } |
184 | |
90fe520e |
185 | # predicates |
186 | |
187 | sub has_accessor { exists $_[0]->{accessor} } |
188 | sub has_reader { exists $_[0]->{reader} } |
189 | sub has_writer { exists $_[0]->{writer} } |
f6715552 |
190 | sub has_predicate { exists $_[0]->{predicate} } |
191 | sub has_clearer { exists $_[0]->{clearer} } |
192 | sub has_handles { exists $_[0]->{handles} } |
90fe520e |
193 | |
194 | sub has_default { exists $_[0]->{default} } |
f6715552 |
195 | sub has_type_constraint { exists $_[0]->{type_constraint} } |
196 | sub has_trigger { exists $_[0]->{trigger} } |
197 | sub has_builder { exists $_[0]->{builder} } |
eec1bb49 |
198 | |
1b9e472d |
199 | sub has_read_method { exists $_[0]->{reader} || exists $_[0]->{accessor} } |
200 | sub has_write_method { exists $_[0]->{writer} || exists $_[0]->{accessor} } |
201 | |
1bfebf5f |
202 | sub _create_args { |
203 | $_[0]->{_create_args} = $_[1] if @_ > 1; |
204 | $_[0]->{_create_args} |
205 | } |
206 | |
90fe520e |
207 | sub accessor_metaclass { 'Mouse::Meta::Method::Accessor' } |
208 | |
87ca293b |
209 | sub interpolate_class{ |
1b9e472d |
210 | my($class, $name, $args) = @_; |
c3398f5b |
211 | |
1b9e472d |
212 | if(my $metaclass = delete $args->{metaclass}){ |
213 | $class = Mouse::Util::resolve_metaclass_alias( Attribute => $metaclass ); |
214 | } |
1bfebf5f |
215 | |
87ca293b |
216 | my @traits; |
1b9e472d |
217 | if(my $traits_ref = delete $args->{traits}){ |
87ca293b |
218 | |
1b9e472d |
219 | for (my $i = 0; $i < @{$traits_ref}; $i++) { |
220 | my $trait = Mouse::Util::resolve_metaclass_alias(Attribute => $traits_ref->[$i], trait => 1); |
b2500191 |
221 | |
1b9e472d |
222 | next if $class->does($trait); |
74be9f76 |
223 | |
1b9e472d |
224 | push @traits, $trait; |
225 | |
226 | # are there options? |
227 | push @traits, $traits_ref->[++$i] |
228 | if ref($traits_ref->[$i+1]); |
c3398f5b |
229 | } |
c3398f5b |
230 | |
1b9e472d |
231 | if (@traits) { |
232 | $class = Mouse::Meta::Class->create_anon_class( |
233 | superclasses => [ $class ], |
234 | roles => \@traits, |
235 | cache => 1, |
236 | )->name; |
1b9e472d |
237 | } |
74be9f76 |
238 | } |
239 | |
87ca293b |
240 | return( $class, @traits ); |
1b9e472d |
241 | } |
242 | |
243 | sub canonicalize_args{ |
244 | my ($self, $name, %args) = @_; |
245 | |
246 | Carp::cluck("$self->canonicalize_args has been deprecated." |
87ca293b |
247 | . "Use \$self->_process_options instead."); |
1b9e472d |
248 | |
249 | return %args; |
250 | } |
251 | |
252 | sub create { |
253 | my ($self, $class, $name, %args) = @_; |
254 | |
255 | Carp::cluck("$self->create has been deprecated." |
256 | . "Use \$meta->add_attribute and \$attr->install_accessors instead."); |
257 | |
258 | # noop |
259 | return $self; |
c3398f5b |
260 | } |
261 | |
20e25eb9 |
262 | sub verify_against_type_constraint { |
f55f60dd |
263 | my ($self, $value) = @_; |
264 | my $tc = $self->type_constraint; |
265 | return 1 unless $tc; |
5aa30ced |
266 | |
f55f60dd |
267 | local $_ = $value; |
268 | return 1 if $tc->check($value); |
5aa30ced |
269 | |
f55f60dd |
270 | $self->verify_type_constraint_error($self->name, $value, $tc); |
b3b74cc6 |
271 | } |
5aa30ced |
272 | |
b3b74cc6 |
273 | sub verify_type_constraint_error { |
274 | my($self, $name, $value, $type) = @_; |
fce211ae |
275 | $self->throw_error("Attribute ($name) does not pass the type constraint because: " . $type->get_message($value)); |
5aa30ced |
276 | } |
277 | |
8a7f2a8a |
278 | sub coerce_constraint { ## my($self, $value) = @_; |
279 | my $type = $_[0]->{type_constraint} |
280 | or return $_[1]; |
684db121 |
281 | return Mouse::Util::TypeConstraints->typecast_constraints($_[0]->associated_class->name, $_[0]->type_constraint, $_[1]); |
4188b837 |
282 | } |
283 | |
af745d5a |
284 | sub _canonicalize_handles { |
285 | my $self = shift; |
286 | my $handles = shift; |
287 | |
288 | if (ref($handles) eq 'HASH') { |
289 | return %$handles; |
290 | } |
291 | elsif (ref($handles) eq 'ARRAY') { |
292 | return map { $_ => $_ } @$handles; |
293 | } |
294 | else { |
fce211ae |
295 | $self->throw_error("Unable to canonicalize the 'handles' option with $handles"); |
af745d5a |
296 | } |
297 | } |
298 | |
1b9e472d |
299 | sub clone_and_inherit_options{ |
300 | my $self = shift; |
301 | my $name = shift; |
302 | |
303 | return ref($self)->new($name, %{$self}, @_ == 1 ? %{$_[0]} : @_); |
304 | } |
305 | |
1bfebf5f |
306 | sub clone_parent { |
307 | my $self = shift; |
308 | my $class = shift; |
309 | my $name = shift; |
310 | my %args = ($self->get_parent_args($class, $name), @_); |
311 | |
1b9e472d |
312 | Carp::cluck("$self->clone_parent has been deprecated." |
313 | . "Use \$meta->add_attribute and \$attr->install_accessors instead."); |
314 | |
315 | |
1bfebf5f |
316 | $self->create($class, $name, %args); |
317 | } |
318 | |
319 | sub get_parent_args { |
320 | my $self = shift; |
321 | my $class = shift; |
322 | my $name = shift; |
323 | |
724c77c0 |
324 | for my $super ($class->linearized_isa) { |
bb733405 |
325 | my $super_attr = $super->can("meta") && $super->meta->get_attribute($name) |
1bfebf5f |
326 | or next; |
327 | return %{ $super_attr->_create_args }; |
328 | } |
329 | |
fce211ae |
330 | $self->throw_error("Could not find an attribute by the name of '$name' to inherit from"); |
331 | } |
332 | |
1b9e472d |
333 | sub install_accessors{ |
334 | my($attribute) = @_; |
335 | |
336 | my $metaclass = $attribute->{associated_class}; |
337 | my $generator_class = $attribute->accessor_metaclass; |
338 | |
339 | foreach my $type(qw(accessor reader writer predicate clearer handles)){ |
340 | if(exists $attribute->{$type}){ |
341 | my $installer = '_install_' . $type; |
342 | $generator_class->$installer($attribute, $attribute->{$type}, $metaclass); |
343 | $attribute->{associated_methods}++; |
344 | } |
345 | } |
346 | |
347 | if($attribute->can('create') != \&create){ |
348 | $attribute->create($metaclass, $attribute->name, %{$attribute}); |
349 | } |
350 | |
351 | return; |
352 | } |
353 | |
fce211ae |
354 | sub throw_error{ |
355 | my $self = shift; |
356 | |
357 | my $metaclass = (ref $self && $self->associated_class) || 'Mouse::Meta::Class'; |
358 | $metaclass->throw_error(@_, depth => 1); |
1bfebf5f |
359 | } |
360 | |
c3398f5b |
361 | 1; |
362 | |
363 | __END__ |
364 | |
365 | =head1 NAME |
366 | |
306290e8 |
367 | Mouse::Meta::Attribute - attribute metaclass |
c3398f5b |
368 | |
369 | =head1 METHODS |
370 | |
306290e8 |
371 | =head2 new %args -> Mouse::Meta::Attribute |
c3398f5b |
372 | |
306290e8 |
373 | Instantiates a new Mouse::Meta::Attribute. Does nothing else. |
c3398f5b |
374 | |
306290e8 |
375 | =head2 create OwnerClass, AttributeName, %args -> Mouse::Meta::Attribute |
c3398f5b |
376 | |
377 | Creates a new attribute in OwnerClass. Accessors and helper methods are |
378 | installed. Some error checking is done. |
379 | |
380 | =head2 name -> AttributeName |
381 | |
181502b9 |
382 | =head2 associated_class -> OwnerClass |
c3398f5b |
383 | |
ab27a55e |
384 | =head2 is_required -> Bool |
c3398f5b |
385 | |
ab27a55e |
386 | =head2 default -> Item |
c3398f5b |
387 | |
ab27a55e |
388 | =head2 has_default -> Bool |
389 | |
390 | =head2 is_lazy -> Bool |
391 | |
392 | =head2 predicate -> MethodName | Undef |
393 | |
394 | =head2 has_predicate -> Bool |
395 | |
396 | =head2 clearer -> MethodName | Undef |
397 | |
398 | =head2 has_clearer -> Bool |
c3398f5b |
399 | |
400 | =head2 handles -> { LocalName => RemoteName } |
401 | |
ab27a55e |
402 | =head2 has_handles -> Bool |
403 | |
3645b316 |
404 | =head2 is_weak_ref -> Bool |
c3398f5b |
405 | |
406 | =head2 init_arg -> Str |
407 | |
ab27a55e |
408 | =head2 type_constraint -> Str |
409 | |
410 | =head2 has_type_constraint -> Bool |
411 | |
412 | =head2 trigger => CODE | Undef |
413 | |
414 | =head2 has_trigger -> Bool |
415 | |
416 | =head2 builder => MethodName | Undef |
417 | |
418 | =head2 has_builder -> Bool |
419 | |
93f08899 |
420 | =head2 is_lazy_build => Bool |
421 | |
0fff36e6 |
422 | =head2 should_auto_deref -> Bool |
423 | |
c3398f5b |
424 | Informational methods. |
425 | |
20e25eb9 |
426 | =head2 verify_against_type_constraint Item -> 1 | ERROR |
fb706f5c |
427 | |
428 | Checks that the given value passes this attribute's type constraint. Returns 1 |
429 | on success, otherwise C<confess>es. |
430 | |
93d190e0 |
431 | =head2 canonicalize_args Name, %args -> %args |
432 | |
433 | Canonicalizes some arguments to create. In particular, C<lazy_build> is |
434 | canonicalized into C<lazy>, C<builder>, etc. |
435 | |
1bbaa8ed |
436 | =head2 validate_args Name, \%args -> 1 | ERROR |
93d190e0 |
437 | |
438 | Checks that the arguments to create the attribute (ie those specified by |
439 | C<has>) are valid. |
440 | |
f7b11a21 |
441 | =head2 clone_parent OwnerClass, AttributeName, %args -> Mouse::Meta::Attribute |
442 | |
443 | Creates a new attribute in OwnerClass, inheriting options from parent classes. |
444 | Accessors and helper methods are installed. Some error checking is done. |
445 | |
446 | =head2 get_parent_args OwnerClass, AttributeName -> Hash |
447 | |
448 | Returns the options that the parent class of C<OwnerClass> used for attribute |
449 | C<AttributeName>. |
450 | |
c3398f5b |
451 | =cut |
452 | |