Commit | Line | Data |
4e036ee4 |
1 | |
2 | package Moose::Meta::TypeConstraint; |
3 | |
4 | use strict; |
5 | use warnings; |
6 | use metaclass; |
7 | |
ed90007b |
8 | use overload '0+' => sub { refaddr(shift) }, # id an object |
9 | '""' => sub { shift->name }, # stringify to tc name |
72e389bf |
10 | bool => sub { 1 }, |
b644e331 |
11 | fallback => 1; |
900466d6 |
12 | |
dabed765 |
13 | use Scalar::Util qw(blessed refaddr); |
9f2230e9 |
14 | use Sub::Name qw(subname); |
66811d63 |
15 | |
e606ae5f |
16 | use base qw(Class::MOP::Object); |
17 | |
3726f905 |
18 | __PACKAGE__->meta->add_attribute('name' => (reader => 'name')); |
19 | __PACKAGE__->meta->add_attribute('parent' => ( |
20 | reader => 'parent', |
21 | predicate => 'has_parent', |
22 | )); |
baf26cc6 |
23 | |
24 | my $null_constraint = sub { 1 }; |
d67145ed |
25 | __PACKAGE__->meta->add_attribute('constraint' => ( |
8de73ff1 |
26 | reader => 'constraint', |
27 | writer => '_set_constraint', |
baf26cc6 |
28 | default => sub { $null_constraint } |
d67145ed |
29 | )); |
76d37e5a |
30 | __PACKAGE__->meta->add_attribute('message' => ( |
31 | accessor => 'message', |
32 | predicate => 'has_message' |
33 | )); |
a27aa600 |
34 | __PACKAGE__->meta->add_attribute('coercion' => ( |
35 | accessor => 'coercion', |
36 | predicate => 'has_coercion' |
37 | )); |
70ea9161 |
38 | |
c8cf9aaa |
39 | __PACKAGE__->meta->add_attribute('hand_optimized_type_constraint' => ( |
40 | init_arg => 'optimized', |
41 | accessor => 'hand_optimized_type_constraint', |
e27dfc11 |
42 | predicate => 'has_hand_optimized_type_constraint', |
c8cf9aaa |
43 | )); |
44 | |
bd72f3c8 |
45 | sub parents { |
46 | my $self; |
47 | $self->parent; |
48 | } |
49 | |
3726f905 |
50 | # private accessors |
51 | |
52 | __PACKAGE__->meta->add_attribute('compiled_type_constraint' => ( |
53 | accessor => '_compiled_type_constraint', |
54 | predicate => '_has_compiled_type_constraint' |
55 | )); |
22aed3c0 |
56 | __PACKAGE__->meta->add_attribute('package_defined_in' => ( |
57 | accessor => '_package_defined_in' |
58 | )); |
59 | |
e27dfc11 |
60 | sub new { |
a27aa600 |
61 | my $class = shift; |
8534c69a |
62 | my ($first, @rest) = @_; |
63 | my %args = ref $first ? %$first : $first ? ($first, @rest) : (); |
64 | $args{name} = $args{name} ? "$args{name}" : "__ANON__"; |
70ea9161 |
65 | |
8534c69a |
66 | my $self = $class->_new(%args); |
3726f905 |
67 | $self->compile_type_constraint() |
68 | unless $self->_has_compiled_type_constraint; |
66811d63 |
69 | return $self; |
70 | } |
71 | |
8534c69a |
72 | |
73 | |
70ea9161 |
74 | sub coerce { |
75 | my $self = shift; |
76 | |
77 | my $coercion = $self->coercion; |
78 | |
79 | unless ($coercion) { |
80 | require Moose; |
81 | Moose->throw_error("Cannot coerce without a type coercion"); |
82 | } |
83 | |
02679ba4 |
84 | return $_[0] if $self->check($_[0]); |
85 | |
70ea9161 |
86 | return $coercion->coerce(@_); |
87 | } |
a1257460 |
88 | |
bb6ac54a |
89 | sub assert_coerce { |
90 | my $self = shift; |
91 | |
92 | my $coercion = $self->coercion; |
93 | |
94 | unless ($coercion) { |
95 | require Moose; |
96 | Moose->throw_error("Cannot coerce without a type coercion"); |
97 | } |
98 | |
99 | return $_[0] if $self->check($_[0]); |
100 | |
101 | my $result = $coercion->coerce(@_); |
102 | |
103 | $self->assert_valid($result); |
104 | |
105 | return $result; |
106 | } |
107 | |
a1257460 |
108 | sub check { |
109 | my ($self, @args) = @_; |
110 | my $constraint_subref = $self->_compiled_type_constraint; |
111 | return $constraint_subref->(@args) ? 1 : undef; |
112 | } |
113 | |
e27dfc11 |
114 | sub validate { |
76d37e5a |
115 | my ($self, $value) = @_; |
116 | if ($self->_compiled_type_constraint->($value)) { |
117 | return undef; |
118 | } |
119 | else { |
688fcdda |
120 | $self->get_message($value); |
76d37e5a |
121 | } |
122 | } |
123 | |
c24269b3 |
124 | sub assert_valid { |
125 | my ($self, $value) = @_; |
126 | |
127 | my $error = $self->validate($value); |
128 | return 1 if ! defined $error; |
129 | |
130 | require Moose; |
131 | Moose->throw_error($error); |
132 | } |
133 | |
688fcdda |
134 | sub get_message { |
135 | my ($self, $value) = @_; |
688fcdda |
136 | if (my $msg = $self->message) { |
137 | local $_ = $value; |
138 | return $msg->($value); |
139 | } |
140 | else { |
d03bd989 |
141 | $value = (defined $value ? overload::StrVal($value) : 'undef'); |
24a9f75e |
142 | return "Validation failed for '" . $self->name . "' with value $value"; |
d03bd989 |
143 | } |
688fcdda |
144 | } |
145 | |
3726f905 |
146 | ## type predicates ... |
147 | |
d9e17f80 |
148 | sub equals { |
149 | my ( $self, $type_or_name ) = @_; |
150 | |
e606ae5f |
151 | my $other = Moose::Util::TypeConstraints::find_type_constraint($type_or_name) or return; |
dabed765 |
152 | |
0677975f |
153 | return 1 if $self == $other; |
dabed765 |
154 | |
155 | if ( $self->has_hand_optimized_type_constraint and $other->has_hand_optimized_type_constraint ) { |
156 | return 1 if $self->hand_optimized_type_constraint == $other->hand_optimized_type_constraint; |
157 | } |
158 | |
159 | return unless $self->constraint == $other->constraint; |
160 | |
161 | if ( $self->has_parent ) { |
162 | return unless $other->has_parent; |
163 | return unless $self->parent->equals( $other->parent ); |
164 | } else { |
165 | return if $other->has_parent; |
166 | } |
d9e17f80 |
167 | |
05a5763c |
168 | return; |
d9e17f80 |
169 | } |
170 | |
b26e162e |
171 | sub is_a_type_of { |
d9e17f80 |
172 | my ($self, $type_or_name) = @_; |
173 | |
e606ae5f |
174 | my $type = Moose::Util::TypeConstraints::find_type_constraint($type_or_name) or return; |
d9e17f80 |
175 | |
176 | ($self->equals($type) || $self->is_subtype_of($type)); |
b26e162e |
177 | } |
178 | |
cce8198b |
179 | sub is_subtype_of { |
d9e17f80 |
180 | my ($self, $type_or_name) = @_; |
181 | |
e606ae5f |
182 | my $type = Moose::Util::TypeConstraints::find_type_constraint($type_or_name) or return; |
d9e17f80 |
183 | |
cce8198b |
184 | my $current = $self; |
d9e17f80 |
185 | |
cce8198b |
186 | while (my $parent = $current->parent) { |
d9e17f80 |
187 | return 1 if $parent->equals($type); |
cce8198b |
188 | $current = $parent; |
189 | } |
d9e17f80 |
190 | |
cce8198b |
191 | return 0; |
192 | } |
193 | |
3726f905 |
194 | ## compiling the type constraint |
195 | |
196 | sub compile_type_constraint { |
197 | my $self = shift; |
198 | $self->_compiled_type_constraint($self->_actually_compile_type_constraint); |
451c8248 |
199 | } |
200 | |
3726f905 |
201 | ## type compilers ... |
202 | |
203 | sub _actually_compile_type_constraint { |
204 | my $self = shift; |
e27dfc11 |
205 | |
3726f905 |
206 | return $self->_compile_hand_optimized_type_constraint |
207 | if $self->has_hand_optimized_type_constraint; |
e27dfc11 |
208 | |
3726f905 |
209 | my $check = $self->constraint; |
70ea9161 |
210 | unless ( defined $check ) { |
211 | require Moose; |
212 | Moose->throw_error( "Could not compile type constraint '" |
e27dfc11 |
213 | . $self->name |
70ea9161 |
214 | . "' because no constraint check" ); |
215 | } |
e27dfc11 |
216 | |
3726f905 |
217 | return $self->_compile_subtype($check) |
218 | if $self->has_parent; |
e27dfc11 |
219 | |
3726f905 |
220 | return $self->_compile_type($check); |
221 | } |
222 | |
223 | sub _compile_hand_optimized_type_constraint { |
224 | my $self = shift; |
e27dfc11 |
225 | |
3726f905 |
226 | my $type_constraint = $self->hand_optimized_type_constraint; |
e27dfc11 |
227 | |
70ea9161 |
228 | unless ( ref $type_constraint ) { |
229 | require Moose; |
230 | Carp::confess ("Hand optimized type constraint for " . $self->name . " is not a code reference"); |
231 | Moose->throw_error("Hand optimized type constraint is not a code reference"); |
232 | } |
42bc21a4 |
233 | |
234 | return $type_constraint; |
3726f905 |
235 | } |
236 | |
237 | sub _compile_subtype { |
238 | my ($self, $check) = @_; |
e27dfc11 |
239 | |
baf26cc6 |
240 | # gather all the parent constraintss in order |
3726f905 |
241 | my @parents; |
baf26cc6 |
242 | my $optimized_parent; |
3726f905 |
243 | foreach my $parent ($self->_collect_all_parents) { |
baf26cc6 |
244 | # if a parent is optimized, the optimized constraint already includes |
245 | # all of its parents tcs, so we can break the loop |
3726f905 |
246 | if ($parent->has_hand_optimized_type_constraint) { |
baf26cc6 |
247 | push @parents => $optimized_parent = $parent->hand_optimized_type_constraint; |
e27dfc11 |
248 | last; |
3726f905 |
249 | } |
250 | else { |
baf26cc6 |
251 | push @parents => $parent->constraint; |
3726f905 |
252 | } |
253 | } |
e27dfc11 |
254 | |
baf26cc6 |
255 | @parents = grep { $_ != $null_constraint } reverse @parents; |
256 | |
257 | unless ( @parents ) { |
258 | return $self->_compile_type($check); |
259 | } elsif( $optimized_parent and @parents == 1 ) { |
260 | # the case of just one optimized parent is optimized to prevent |
261 | # looping and the unnecessary localization |
b5981f07 |
262 | if ( $check == $null_constraint ) { |
263 | return $optimized_parent; |
264 | } else { |
9f2230e9 |
265 | return subname($self->name, sub { |
b5981f07 |
266 | return undef unless $optimized_parent->($_[0]); |
a1257460 |
267 | my (@args) = @_; |
268 | local $_ = $args[0]; |
269 | $check->(@args); |
b5981f07 |
270 | }); |
271 | } |
baf26cc6 |
272 | } else { |
273 | # general case, check all the constraints, from the first parent to ourselves |
b5981f07 |
274 | my @checks = @parents; |
275 | push @checks, $check if $check != $null_constraint; |
9f2230e9 |
276 | return subname($self->name => sub { |
a1257460 |
277 | my (@args) = @_; |
278 | local $_ = $args[0]; |
baf26cc6 |
279 | foreach my $check (@checks) { |
a1257460 |
280 | return undef unless $check->(@args); |
baf26cc6 |
281 | } |
282 | return 1; |
283 | }); |
284 | } |
3726f905 |
285 | } |
286 | |
287 | sub _compile_type { |
288 | my ($self, $check) = @_; |
baf26cc6 |
289 | |
290 | return $check if $check == $null_constraint; # Item, Any |
291 | |
9f2230e9 |
292 | return subname($self->name => sub { |
a1257460 |
293 | my (@args) = @_; |
294 | local $_ = $args[0]; |
295 | $check->(@args); |
1b2aea39 |
296 | }); |
3726f905 |
297 | } |
298 | |
299 | ## other utils ... |
300 | |
301 | sub _collect_all_parents { |
302 | my $self = shift; |
303 | my @parents; |
304 | my $current = $self->parent; |
305 | while (defined $current) { |
306 | push @parents => $current; |
307 | $current = $current->parent; |
308 | } |
309 | return @parents; |
310 | } |
311 | |
85a9908f |
312 | sub create_child_type { |
9ceb576e |
313 | my ($self, %opts) = @_; |
314 | my $class = ref $self; |
315 | return $class->new(%opts, parent => $self); |
316 | } |
317 | |
4e036ee4 |
318 | 1; |
319 | |
ad46f524 |
320 | # ABSTRACT: The Moose Type Constraint metaclass |
321 | |
4e036ee4 |
322 | __END__ |
323 | |
324 | =pod |
325 | |
4e036ee4 |
326 | =head1 DESCRIPTION |
327 | |
cfd006f0 |
328 | This class represents a single type constraint. Moose's built-in type |
76127c77 |
329 | constraints, as well as constraints you define, are all stored in a |
cfd006f0 |
330 | L<Moose::Meta::TypeConstraint::Registry> object as objects of this |
331 | class. |
6ba6d68c |
332 | |
baf46b9e |
333 | =head1 INHERITANCE |
334 | |
335 | C<Moose::Meta::TypeConstraint> is a subclass of L<Class::MOP::Object>. |
336 | |
4e036ee4 |
337 | =head1 METHODS |
338 | |
339 | =over 4 |
340 | |
cfd006f0 |
341 | =item B<< Moose::Meta::TypeConstraint->new(%options) >> |
4e036ee4 |
342 | |
cfd006f0 |
343 | This creates a new type constraint based on the provided C<%options>: |
4e036ee4 |
344 | |
cfd006f0 |
345 | =over 8 |
d9e17f80 |
346 | |
cfd006f0 |
347 | =item * name |
e606ae5f |
348 | |
cfd006f0 |
349 | The constraint name. If a name is not provided, it will be set to |
350 | "__ANON__". |
b26e162e |
351 | |
cfd006f0 |
352 | =item * parent |
b26e162e |
353 | |
cfd006f0 |
354 | A C<Moose::Meta::TypeConstraint> object which is the parent type for |
355 | the type being created. This is optional. |
cce8198b |
356 | |
cfd006f0 |
357 | =item * constraint |
e606ae5f |
358 | |
cfd006f0 |
359 | This is the subroutine reference that implements the actual constraint |
360 | check. This defaults to a subroutine which always returns true. |
6ba6d68c |
361 | |
cfd006f0 |
362 | =item * message |
0a5bd159 |
363 | |
cfd006f0 |
364 | A subroutine reference which is used to generate an error message when |
365 | the constraint fails. This is optional. |
0a5bd159 |
366 | |
cfd006f0 |
367 | =item * coercion |
76d37e5a |
368 | |
cfd006f0 |
369 | A L<Moose::Meta::TypeCoercion> object representing the coercions to |
370 | the type. This is optional. |
76d37e5a |
371 | |
cfd006f0 |
372 | =item * optimized |
76d37e5a |
373 | |
cfd006f0 |
374 | This is a variant of the C<constraint> parameter that is somehow |
375 | optimized. Typically, this means incorporating both the type's |
376 | constraint and all of its parents' constraints into a single |
377 | subroutine reference. |
6ba6d68c |
378 | |
cfd006f0 |
379 | =back |
4e036ee4 |
380 | |
cfd006f0 |
381 | =item B<< $constraint->equals($type_name_or_object) >> |
e606ae5f |
382 | |
cfd006f0 |
383 | Returns true if the supplied name or type object is the same as the |
384 | current type. |
66811d63 |
385 | |
cfd006f0 |
386 | =item B<< $constraint->is_subtype_of($type_name_or_object) >> |
e606ae5f |
387 | |
cfd006f0 |
388 | Returns true if the supplied name or type object is a parent of the |
389 | current type. |
3726f905 |
390 | |
cfd006f0 |
391 | =item B<< $constraint->is_a_type_of($type_name_or_object) >> |
e606ae5f |
392 | |
cfd006f0 |
393 | Returns true if the given type is the same as the current type, or is |
394 | a parent of the current type. This is a shortcut for checking |
395 | C<equals> and C<is_subtype_of>. |
d9e17f80 |
396 | |
cfd006f0 |
397 | =item B<< $constraint->coerce($value) >> |
2f7e4042 |
398 | |
b2894aea |
399 | This will attempt to coerce the value to the type. If the type does not |
cfd006f0 |
400 | have any defined coercions this will throw an error. |
66811d63 |
401 | |
572b5187 |
402 | If no coercion can produce a value matching C<$constraint>, the original |
403 | value is returned. |
404 | |
086c6b6c |
405 | =item B<< $constraint->assert_coerce($value) >> |
572b5187 |
406 | |
407 | This method behaves just like C<coerce>, but if the result is not valid |
408 | according to C<$constraint>, an error is thrown. |
409 | |
cfd006f0 |
410 | =item B<< $constraint->check($value) >> |
2f7e4042 |
411 | |
cfd006f0 |
412 | Returns true if the given value passes the constraint for the type. |
76d37e5a |
413 | |
cfd006f0 |
414 | =item B<< $constraint->validate($value) >> |
2f7e4042 |
415 | |
cfd006f0 |
416 | This is similar to C<check>. However, if the type I<is valid> then the |
417 | method returns an explicit C<undef>. If the type is not valid, we call |
418 | C<< $self->get_message($value) >> internally to generate an error |
419 | message. |
76d37e5a |
420 | |
952320e0 |
421 | =item B<< $constraint->assert_valid($value) >> |
422 | |
423 | Like C<check> and C<validate>, this method checks whether C<$value> is |
424 | valid under the constraint. If it is, it will return true. If it is not, |
425 | an exception will be thrown with the results of |
426 | C<< $self->get_message($value) >>. |
427 | |
cfd006f0 |
428 | =item B<< $constraint->name >> |
2f7e4042 |
429 | |
cfd006f0 |
430 | Returns the type's name, as provided to the constructor. |
688fcdda |
431 | |
cfd006f0 |
432 | =item B<< $constraint->parent >> |
2f7e4042 |
433 | |
cfd006f0 |
434 | Returns the type's parent, as provided to the constructor, if any. |
4e036ee4 |
435 | |
cfd006f0 |
436 | =item B<< $constraint->has_parent >> |
2f7e4042 |
437 | |
cfd006f0 |
438 | Returns true if the type has a parent type. |
a27aa600 |
439 | |
cfd006f0 |
440 | =item B<< $constraint->parents >> |
2f7e4042 |
441 | |
cfd006f0 |
442 | A synonym for C<parent>. This is useful for polymorphism with types |
443 | that can have more than one parent. |
c8cf9aaa |
444 | |
cfd006f0 |
445 | =item B<< $constraint->constraint >> |
c8cf9aaa |
446 | |
cfd006f0 |
447 | Returns the type's constraint, as provided to the constructor. |
9ceb576e |
448 | |
cfd006f0 |
449 | =item B<< $constraint->get_message($value) >> |
4e036ee4 |
450 | |
cfd006f0 |
451 | This generates a method for the given value. If the type does not have |
452 | an explicit message, we generate a default message. |
3726f905 |
453 | |
cfd006f0 |
454 | =item B<< $constraint->has_message >> |
455 | |
456 | Returns true if the type has a message. |
457 | |
458 | =item B<< $constraint->message >> |
459 | |
460 | Returns the type's message as a subroutine reference. |
461 | |
462 | =item B<< $constraint->coercion >> |
463 | |
464 | Returns the type's L<Moose::Meta::TypeCoercion> object, if one |
465 | exists. |
466 | |
467 | =item B<< $constraint->has_coercion >> |
468 | |
469 | Returns true if the type has a coercion. |
470 | |
471 | =item B<< $constraint->hand_optimized_type_constraint >> |
472 | |
473 | Returns the type's hand optimized constraint, as provided to the |
474 | constructor via the C<optimized> option. |
475 | |
476 | =item B<< $constraint->has_hand_optimized_type_constraint >> |
477 | |
478 | Returns true if the type has an optimized constraint. |
479 | |
480 | =item B<< $constraint->create_child_type(%options) >> |
451c8248 |
481 | |
cfd006f0 |
482 | This returns a new type constraint of the same class using the |
483 | provided C<%options>. The C<parent> option will be the current type. |
3726f905 |
484 | |
cfd006f0 |
485 | This method exists so that subclasses of this class can override this |
486 | behavior and change how child types are created. |
451c8248 |
487 | |
488 | =back |
489 | |
4e036ee4 |
490 | =head1 BUGS |
491 | |
d4048ef3 |
492 | See L<Moose/BUGS> for details on reporting bugs. |
4e036ee4 |
493 | |
c8cf9aaa |
494 | =cut |