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); |
5a18346b |
15 | use Try::Tiny; |
66811d63 |
16 | |
e606ae5f |
17 | use base qw(Class::MOP::Object); |
18 | |
3726f905 |
19 | __PACKAGE__->meta->add_attribute('name' => (reader => 'name')); |
20 | __PACKAGE__->meta->add_attribute('parent' => ( |
21 | reader => 'parent', |
22 | predicate => 'has_parent', |
23 | )); |
baf26cc6 |
24 | |
25 | my $null_constraint = sub { 1 }; |
d67145ed |
26 | __PACKAGE__->meta->add_attribute('constraint' => ( |
8de73ff1 |
27 | reader => 'constraint', |
28 | writer => '_set_constraint', |
baf26cc6 |
29 | default => sub { $null_constraint } |
d67145ed |
30 | )); |
76d37e5a |
31 | __PACKAGE__->meta->add_attribute('message' => ( |
32 | accessor => 'message', |
33 | predicate => 'has_message' |
34 | )); |
a27aa600 |
35 | __PACKAGE__->meta->add_attribute('coercion' => ( |
36 | accessor => 'coercion', |
37 | predicate => 'has_coercion' |
38 | )); |
70ea9161 |
39 | |
c8cf9aaa |
40 | __PACKAGE__->meta->add_attribute('hand_optimized_type_constraint' => ( |
41 | init_arg => 'optimized', |
42 | accessor => 'hand_optimized_type_constraint', |
e27dfc11 |
43 | predicate => 'has_hand_optimized_type_constraint', |
c8cf9aaa |
44 | )); |
45 | |
bd72f3c8 |
46 | sub parents { |
47 | my $self; |
48 | $self->parent; |
49 | } |
50 | |
3726f905 |
51 | # private accessors |
52 | |
53 | __PACKAGE__->meta->add_attribute('compiled_type_constraint' => ( |
54 | accessor => '_compiled_type_constraint', |
55 | predicate => '_has_compiled_type_constraint' |
56 | )); |
22aed3c0 |
57 | __PACKAGE__->meta->add_attribute('package_defined_in' => ( |
58 | accessor => '_package_defined_in' |
59 | )); |
60 | |
e27dfc11 |
61 | sub new { |
a27aa600 |
62 | my $class = shift; |
8534c69a |
63 | my ($first, @rest) = @_; |
64 | my %args = ref $first ? %$first : $first ? ($first, @rest) : (); |
65 | $args{name} = $args{name} ? "$args{name}" : "__ANON__"; |
70ea9161 |
66 | |
8534c69a |
67 | my $self = $class->_new(%args); |
3726f905 |
68 | $self->compile_type_constraint() |
69 | unless $self->_has_compiled_type_constraint; |
66811d63 |
70 | return $self; |
71 | } |
72 | |
8534c69a |
73 | |
74 | |
70ea9161 |
75 | sub coerce { |
76 | my $self = shift; |
77 | |
78 | my $coercion = $self->coercion; |
79 | |
80 | unless ($coercion) { |
81 | require Moose; |
82 | Moose->throw_error("Cannot coerce without a type coercion"); |
83 | } |
84 | |
02679ba4 |
85 | return $_[0] if $self->check($_[0]); |
86 | |
70ea9161 |
87 | return $coercion->coerce(@_); |
88 | } |
a1257460 |
89 | |
bb6ac54a |
90 | sub assert_coerce { |
91 | my $self = shift; |
92 | |
93 | my $coercion = $self->coercion; |
94 | |
95 | unless ($coercion) { |
96 | require Moose; |
97 | Moose->throw_error("Cannot coerce without a type coercion"); |
98 | } |
99 | |
100 | return $_[0] if $self->check($_[0]); |
101 | |
102 | my $result = $coercion->coerce(@_); |
103 | |
104 | $self->assert_valid($result); |
105 | |
106 | return $result; |
107 | } |
108 | |
a1257460 |
109 | sub check { |
110 | my ($self, @args) = @_; |
111 | my $constraint_subref = $self->_compiled_type_constraint; |
112 | return $constraint_subref->(@args) ? 1 : undef; |
113 | } |
114 | |
e27dfc11 |
115 | sub validate { |
76d37e5a |
116 | my ($self, $value) = @_; |
117 | if ($self->_compiled_type_constraint->($value)) { |
118 | return undef; |
119 | } |
120 | else { |
688fcdda |
121 | $self->get_message($value); |
76d37e5a |
122 | } |
123 | } |
124 | |
c24269b3 |
125 | sub assert_valid { |
126 | my ($self, $value) = @_; |
127 | |
128 | my $error = $self->validate($value); |
129 | return 1 if ! defined $error; |
130 | |
131 | require Moose; |
132 | Moose->throw_error($error); |
133 | } |
134 | |
688fcdda |
135 | sub get_message { |
136 | my ($self, $value) = @_; |
688fcdda |
137 | if (my $msg = $self->message) { |
138 | local $_ = $value; |
139 | return $msg->($value); |
140 | } |
141 | else { |
5a18346b |
142 | # have to load it late like this, since it uses Moose itself |
143 | if (try { Class::MOP::load_class('Devel::PartialDump'); 1 }) { |
144 | $value = Devel::PartialDump->new->dump($value); |
145 | } |
146 | else { |
147 | $value = (defined $value ? overload::StrVal($value) : 'undef'); |
148 | } |
24a9f75e |
149 | return "Validation failed for '" . $self->name . "' with value $value"; |
d03bd989 |
150 | } |
688fcdda |
151 | } |
152 | |
3726f905 |
153 | ## type predicates ... |
154 | |
d9e17f80 |
155 | sub equals { |
156 | my ( $self, $type_or_name ) = @_; |
157 | |
e606ae5f |
158 | my $other = Moose::Util::TypeConstraints::find_type_constraint($type_or_name) or return; |
dabed765 |
159 | |
0677975f |
160 | return 1 if $self == $other; |
dabed765 |
161 | |
162 | if ( $self->has_hand_optimized_type_constraint and $other->has_hand_optimized_type_constraint ) { |
163 | return 1 if $self->hand_optimized_type_constraint == $other->hand_optimized_type_constraint; |
164 | } |
165 | |
166 | return unless $self->constraint == $other->constraint; |
167 | |
168 | if ( $self->has_parent ) { |
169 | return unless $other->has_parent; |
170 | return unless $self->parent->equals( $other->parent ); |
171 | } else { |
172 | return if $other->has_parent; |
173 | } |
d9e17f80 |
174 | |
05a5763c |
175 | return; |
d9e17f80 |
176 | } |
177 | |
b26e162e |
178 | sub is_a_type_of { |
d9e17f80 |
179 | my ($self, $type_or_name) = @_; |
180 | |
e606ae5f |
181 | my $type = Moose::Util::TypeConstraints::find_type_constraint($type_or_name) or return; |
d9e17f80 |
182 | |
183 | ($self->equals($type) || $self->is_subtype_of($type)); |
b26e162e |
184 | } |
185 | |
cce8198b |
186 | sub is_subtype_of { |
d9e17f80 |
187 | my ($self, $type_or_name) = @_; |
188 | |
e606ae5f |
189 | my $type = Moose::Util::TypeConstraints::find_type_constraint($type_or_name) or return; |
d9e17f80 |
190 | |
cce8198b |
191 | my $current = $self; |
d9e17f80 |
192 | |
cce8198b |
193 | while (my $parent = $current->parent) { |
d9e17f80 |
194 | return 1 if $parent->equals($type); |
cce8198b |
195 | $current = $parent; |
196 | } |
d9e17f80 |
197 | |
cce8198b |
198 | return 0; |
199 | } |
200 | |
3726f905 |
201 | ## compiling the type constraint |
202 | |
203 | sub compile_type_constraint { |
204 | my $self = shift; |
205 | $self->_compiled_type_constraint($self->_actually_compile_type_constraint); |
451c8248 |
206 | } |
207 | |
3726f905 |
208 | ## type compilers ... |
209 | |
210 | sub _actually_compile_type_constraint { |
211 | my $self = shift; |
e27dfc11 |
212 | |
3726f905 |
213 | return $self->_compile_hand_optimized_type_constraint |
214 | if $self->has_hand_optimized_type_constraint; |
e27dfc11 |
215 | |
3726f905 |
216 | my $check = $self->constraint; |
70ea9161 |
217 | unless ( defined $check ) { |
218 | require Moose; |
219 | Moose->throw_error( "Could not compile type constraint '" |
e27dfc11 |
220 | . $self->name |
70ea9161 |
221 | . "' because no constraint check" ); |
222 | } |
e27dfc11 |
223 | |
3726f905 |
224 | return $self->_compile_subtype($check) |
225 | if $self->has_parent; |
e27dfc11 |
226 | |
3726f905 |
227 | return $self->_compile_type($check); |
228 | } |
229 | |
230 | sub _compile_hand_optimized_type_constraint { |
231 | my $self = shift; |
e27dfc11 |
232 | |
3726f905 |
233 | my $type_constraint = $self->hand_optimized_type_constraint; |
e27dfc11 |
234 | |
70ea9161 |
235 | unless ( ref $type_constraint ) { |
236 | require Moose; |
237 | Carp::confess ("Hand optimized type constraint for " . $self->name . " is not a code reference"); |
238 | Moose->throw_error("Hand optimized type constraint is not a code reference"); |
239 | } |
42bc21a4 |
240 | |
241 | return $type_constraint; |
3726f905 |
242 | } |
243 | |
244 | sub _compile_subtype { |
245 | my ($self, $check) = @_; |
e27dfc11 |
246 | |
baf26cc6 |
247 | # gather all the parent constraintss in order |
3726f905 |
248 | my @parents; |
baf26cc6 |
249 | my $optimized_parent; |
3726f905 |
250 | foreach my $parent ($self->_collect_all_parents) { |
baf26cc6 |
251 | # if a parent is optimized, the optimized constraint already includes |
252 | # all of its parents tcs, so we can break the loop |
3726f905 |
253 | if ($parent->has_hand_optimized_type_constraint) { |
baf26cc6 |
254 | push @parents => $optimized_parent = $parent->hand_optimized_type_constraint; |
e27dfc11 |
255 | last; |
3726f905 |
256 | } |
257 | else { |
baf26cc6 |
258 | push @parents => $parent->constraint; |
3726f905 |
259 | } |
260 | } |
e27dfc11 |
261 | |
baf26cc6 |
262 | @parents = grep { $_ != $null_constraint } reverse @parents; |
263 | |
264 | unless ( @parents ) { |
265 | return $self->_compile_type($check); |
266 | } elsif( $optimized_parent and @parents == 1 ) { |
267 | # the case of just one optimized parent is optimized to prevent |
268 | # looping and the unnecessary localization |
b5981f07 |
269 | if ( $check == $null_constraint ) { |
270 | return $optimized_parent; |
271 | } else { |
9f2230e9 |
272 | return subname($self->name, sub { |
b5981f07 |
273 | return undef unless $optimized_parent->($_[0]); |
a1257460 |
274 | my (@args) = @_; |
275 | local $_ = $args[0]; |
276 | $check->(@args); |
b5981f07 |
277 | }); |
278 | } |
baf26cc6 |
279 | } else { |
280 | # general case, check all the constraints, from the first parent to ourselves |
b5981f07 |
281 | my @checks = @parents; |
282 | push @checks, $check if $check != $null_constraint; |
9f2230e9 |
283 | return subname($self->name => sub { |
a1257460 |
284 | my (@args) = @_; |
285 | local $_ = $args[0]; |
baf26cc6 |
286 | foreach my $check (@checks) { |
a1257460 |
287 | return undef unless $check->(@args); |
baf26cc6 |
288 | } |
289 | return 1; |
290 | }); |
291 | } |
3726f905 |
292 | } |
293 | |
294 | sub _compile_type { |
295 | my ($self, $check) = @_; |
baf26cc6 |
296 | |
297 | return $check if $check == $null_constraint; # Item, Any |
298 | |
9f2230e9 |
299 | return subname($self->name => sub { |
a1257460 |
300 | my (@args) = @_; |
301 | local $_ = $args[0]; |
302 | $check->(@args); |
1b2aea39 |
303 | }); |
3726f905 |
304 | } |
305 | |
306 | ## other utils ... |
307 | |
308 | sub _collect_all_parents { |
309 | my $self = shift; |
310 | my @parents; |
311 | my $current = $self->parent; |
312 | while (defined $current) { |
313 | push @parents => $current; |
314 | $current = $current->parent; |
315 | } |
316 | return @parents; |
317 | } |
318 | |
85a9908f |
319 | sub create_child_type { |
9ceb576e |
320 | my ($self, %opts) = @_; |
321 | my $class = ref $self; |
322 | return $class->new(%opts, parent => $self); |
323 | } |
324 | |
4e036ee4 |
325 | 1; |
326 | |
ad46f524 |
327 | # ABSTRACT: The Moose Type Constraint metaclass |
328 | |
4e036ee4 |
329 | __END__ |
330 | |
331 | =pod |
332 | |
4e036ee4 |
333 | =head1 DESCRIPTION |
334 | |
cfd006f0 |
335 | This class represents a single type constraint. Moose's built-in type |
76127c77 |
336 | constraints, as well as constraints you define, are all stored in a |
cfd006f0 |
337 | L<Moose::Meta::TypeConstraint::Registry> object as objects of this |
338 | class. |
6ba6d68c |
339 | |
baf46b9e |
340 | =head1 INHERITANCE |
341 | |
342 | C<Moose::Meta::TypeConstraint> is a subclass of L<Class::MOP::Object>. |
343 | |
4e036ee4 |
344 | =head1 METHODS |
345 | |
346 | =over 4 |
347 | |
cfd006f0 |
348 | =item B<< Moose::Meta::TypeConstraint->new(%options) >> |
4e036ee4 |
349 | |
cfd006f0 |
350 | This creates a new type constraint based on the provided C<%options>: |
4e036ee4 |
351 | |
cfd006f0 |
352 | =over 8 |
d9e17f80 |
353 | |
cfd006f0 |
354 | =item * name |
e606ae5f |
355 | |
cfd006f0 |
356 | The constraint name. If a name is not provided, it will be set to |
357 | "__ANON__". |
b26e162e |
358 | |
cfd006f0 |
359 | =item * parent |
b26e162e |
360 | |
cfd006f0 |
361 | A C<Moose::Meta::TypeConstraint> object which is the parent type for |
362 | the type being created. This is optional. |
cce8198b |
363 | |
cfd006f0 |
364 | =item * constraint |
e606ae5f |
365 | |
cfd006f0 |
366 | This is the subroutine reference that implements the actual constraint |
367 | check. This defaults to a subroutine which always returns true. |
6ba6d68c |
368 | |
cfd006f0 |
369 | =item * message |
0a5bd159 |
370 | |
cfd006f0 |
371 | A subroutine reference which is used to generate an error message when |
372 | the constraint fails. This is optional. |
0a5bd159 |
373 | |
cfd006f0 |
374 | =item * coercion |
76d37e5a |
375 | |
cfd006f0 |
376 | A L<Moose::Meta::TypeCoercion> object representing the coercions to |
377 | the type. This is optional. |
76d37e5a |
378 | |
cfd006f0 |
379 | =item * optimized |
76d37e5a |
380 | |
cfd006f0 |
381 | This is a variant of the C<constraint> parameter that is somehow |
382 | optimized. Typically, this means incorporating both the type's |
383 | constraint and all of its parents' constraints into a single |
384 | subroutine reference. |
6ba6d68c |
385 | |
cfd006f0 |
386 | =back |
4e036ee4 |
387 | |
cfd006f0 |
388 | =item B<< $constraint->equals($type_name_or_object) >> |
e606ae5f |
389 | |
cfd006f0 |
390 | Returns true if the supplied name or type object is the same as the |
391 | current type. |
66811d63 |
392 | |
cfd006f0 |
393 | =item B<< $constraint->is_subtype_of($type_name_or_object) >> |
e606ae5f |
394 | |
cfd006f0 |
395 | Returns true if the supplied name or type object is a parent of the |
396 | current type. |
3726f905 |
397 | |
cfd006f0 |
398 | =item B<< $constraint->is_a_type_of($type_name_or_object) >> |
e606ae5f |
399 | |
cfd006f0 |
400 | Returns true if the given type is the same as the current type, or is |
401 | a parent of the current type. This is a shortcut for checking |
402 | C<equals> and C<is_subtype_of>. |
d9e17f80 |
403 | |
cfd006f0 |
404 | =item B<< $constraint->coerce($value) >> |
2f7e4042 |
405 | |
b2894aea |
406 | This will attempt to coerce the value to the type. If the type does not |
cfd006f0 |
407 | have any defined coercions this will throw an error. |
66811d63 |
408 | |
572b5187 |
409 | If no coercion can produce a value matching C<$constraint>, the original |
410 | value is returned. |
411 | |
086c6b6c |
412 | =item B<< $constraint->assert_coerce($value) >> |
572b5187 |
413 | |
414 | This method behaves just like C<coerce>, but if the result is not valid |
415 | according to C<$constraint>, an error is thrown. |
416 | |
cfd006f0 |
417 | =item B<< $constraint->check($value) >> |
2f7e4042 |
418 | |
cfd006f0 |
419 | Returns true if the given value passes the constraint for the type. |
76d37e5a |
420 | |
cfd006f0 |
421 | =item B<< $constraint->validate($value) >> |
2f7e4042 |
422 | |
cfd006f0 |
423 | This is similar to C<check>. However, if the type I<is valid> then the |
424 | method returns an explicit C<undef>. If the type is not valid, we call |
425 | C<< $self->get_message($value) >> internally to generate an error |
426 | message. |
76d37e5a |
427 | |
952320e0 |
428 | =item B<< $constraint->assert_valid($value) >> |
429 | |
430 | Like C<check> and C<validate>, this method checks whether C<$value> is |
431 | valid under the constraint. If it is, it will return true. If it is not, |
432 | an exception will be thrown with the results of |
433 | C<< $self->get_message($value) >>. |
434 | |
cfd006f0 |
435 | =item B<< $constraint->name >> |
2f7e4042 |
436 | |
cfd006f0 |
437 | Returns the type's name, as provided to the constructor. |
688fcdda |
438 | |
cfd006f0 |
439 | =item B<< $constraint->parent >> |
2f7e4042 |
440 | |
cfd006f0 |
441 | Returns the type's parent, as provided to the constructor, if any. |
4e036ee4 |
442 | |
cfd006f0 |
443 | =item B<< $constraint->has_parent >> |
2f7e4042 |
444 | |
cfd006f0 |
445 | Returns true if the type has a parent type. |
a27aa600 |
446 | |
cfd006f0 |
447 | =item B<< $constraint->parents >> |
2f7e4042 |
448 | |
cfd006f0 |
449 | A synonym for C<parent>. This is useful for polymorphism with types |
450 | that can have more than one parent. |
c8cf9aaa |
451 | |
cfd006f0 |
452 | =item B<< $constraint->constraint >> |
c8cf9aaa |
453 | |
cfd006f0 |
454 | Returns the type's constraint, as provided to the constructor. |
9ceb576e |
455 | |
cfd006f0 |
456 | =item B<< $constraint->get_message($value) >> |
4e036ee4 |
457 | |
cfd006f0 |
458 | This generates a method for the given value. If the type does not have |
459 | an explicit message, we generate a default message. |
3726f905 |
460 | |
cfd006f0 |
461 | =item B<< $constraint->has_message >> |
462 | |
463 | Returns true if the type has a message. |
464 | |
465 | =item B<< $constraint->message >> |
466 | |
467 | Returns the type's message as a subroutine reference. |
468 | |
469 | =item B<< $constraint->coercion >> |
470 | |
471 | Returns the type's L<Moose::Meta::TypeCoercion> object, if one |
472 | exists. |
473 | |
474 | =item B<< $constraint->has_coercion >> |
475 | |
476 | Returns true if the type has a coercion. |
477 | |
478 | =item B<< $constraint->hand_optimized_type_constraint >> |
479 | |
480 | Returns the type's hand optimized constraint, as provided to the |
481 | constructor via the C<optimized> option. |
482 | |
483 | =item B<< $constraint->has_hand_optimized_type_constraint >> |
484 | |
485 | Returns true if the type has an optimized constraint. |
486 | |
487 | =item B<< $constraint->create_child_type(%options) >> |
451c8248 |
488 | |
cfd006f0 |
489 | This returns a new type constraint of the same class using the |
490 | provided C<%options>. The C<parent> option will be the current type. |
3726f905 |
491 | |
cfd006f0 |
492 | This method exists so that subclasses of this class can override this |
493 | behavior and change how child types are created. |
451c8248 |
494 | |
495 | =back |
496 | |
4e036ee4 |
497 | =head1 BUGS |
498 | |
d4048ef3 |
499 | See L<Moose/BUGS> for details on reporting bugs. |
4e036ee4 |
500 | |
c8cf9aaa |
501 | =cut |