Commit | Line | Data |
4e036ee4 |
1 | |
2 | package Moose::Meta::TypeConstraint; |
3 | |
4 | use strict; |
5 | use warnings; |
6 | use metaclass; |
7 | |
b644e331 |
8 | use overload '""' => sub { shift->name }, # stringify to tc name |
9 | fallback => 1; |
900466d6 |
10 | |
dabed765 |
11 | use Scalar::Util qw(blessed refaddr); |
66811d63 |
12 | |
e606ae5f |
13 | use base qw(Class::MOP::Object); |
14 | |
74397c13 |
15 | our $VERSION = '0.75_01'; |
e606ae5f |
16 | $VERSION = eval $VERSION; |
d44714be |
17 | our $AUTHORITY = 'cpan:STEVAN'; |
66811d63 |
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 $coercion->coerce(@_); |
88 | } |
a1257460 |
89 | |
90 | sub check { |
91 | my ($self, @args) = @_; |
92 | my $constraint_subref = $self->_compiled_type_constraint; |
93 | return $constraint_subref->(@args) ? 1 : undef; |
94 | } |
95 | |
e27dfc11 |
96 | sub validate { |
76d37e5a |
97 | my ($self, $value) = @_; |
98 | if ($self->_compiled_type_constraint->($value)) { |
99 | return undef; |
100 | } |
101 | else { |
688fcdda |
102 | $self->get_message($value); |
76d37e5a |
103 | } |
104 | } |
105 | |
688fcdda |
106 | sub get_message { |
107 | my ($self, $value) = @_; |
688fcdda |
108 | if (my $msg = $self->message) { |
109 | local $_ = $value; |
110 | return $msg->($value); |
111 | } |
112 | else { |
e606ae5f |
113 | $value = (defined $value ? overload::StrVal($value) : 'undef'); |
688fcdda |
114 | return "Validation failed for '" . $self->name . "' failed with value $value"; |
115 | } |
116 | } |
117 | |
3726f905 |
118 | ## type predicates ... |
119 | |
d9e17f80 |
120 | sub equals { |
121 | my ( $self, $type_or_name ) = @_; |
122 | |
e606ae5f |
123 | my $other = Moose::Util::TypeConstraints::find_type_constraint($type_or_name) or return; |
dabed765 |
124 | |
125 | return 1 if refaddr($self) == refaddr($other); |
126 | |
127 | if ( $self->has_hand_optimized_type_constraint and $other->has_hand_optimized_type_constraint ) { |
128 | return 1 if $self->hand_optimized_type_constraint == $other->hand_optimized_type_constraint; |
129 | } |
130 | |
131 | return unless $self->constraint == $other->constraint; |
132 | |
133 | if ( $self->has_parent ) { |
134 | return unless $other->has_parent; |
135 | return unless $self->parent->equals( $other->parent ); |
136 | } else { |
137 | return if $other->has_parent; |
138 | } |
d9e17f80 |
139 | |
dabed765 |
140 | return 1; |
d9e17f80 |
141 | } |
142 | |
b26e162e |
143 | sub is_a_type_of { |
d9e17f80 |
144 | my ($self, $type_or_name) = @_; |
145 | |
e606ae5f |
146 | my $type = Moose::Util::TypeConstraints::find_type_constraint($type_or_name) or return; |
d9e17f80 |
147 | |
148 | ($self->equals($type) || $self->is_subtype_of($type)); |
b26e162e |
149 | } |
150 | |
cce8198b |
151 | sub is_subtype_of { |
d9e17f80 |
152 | my ($self, $type_or_name) = @_; |
153 | |
e606ae5f |
154 | my $type = Moose::Util::TypeConstraints::find_type_constraint($type_or_name) or return; |
d9e17f80 |
155 | |
cce8198b |
156 | my $current = $self; |
d9e17f80 |
157 | |
cce8198b |
158 | while (my $parent = $current->parent) { |
d9e17f80 |
159 | return 1 if $parent->equals($type); |
cce8198b |
160 | $current = $parent; |
161 | } |
d9e17f80 |
162 | |
cce8198b |
163 | return 0; |
164 | } |
165 | |
3726f905 |
166 | ## compiling the type constraint |
167 | |
168 | sub compile_type_constraint { |
169 | my $self = shift; |
170 | $self->_compiled_type_constraint($self->_actually_compile_type_constraint); |
451c8248 |
171 | } |
172 | |
3726f905 |
173 | ## type compilers ... |
174 | |
175 | sub _actually_compile_type_constraint { |
176 | my $self = shift; |
e27dfc11 |
177 | |
3726f905 |
178 | return $self->_compile_hand_optimized_type_constraint |
179 | if $self->has_hand_optimized_type_constraint; |
e27dfc11 |
180 | |
3726f905 |
181 | my $check = $self->constraint; |
70ea9161 |
182 | unless ( defined $check ) { |
183 | require Moose; |
184 | Moose->throw_error( "Could not compile type constraint '" |
e27dfc11 |
185 | . $self->name |
70ea9161 |
186 | . "' because no constraint check" ); |
187 | } |
e27dfc11 |
188 | |
3726f905 |
189 | return $self->_compile_subtype($check) |
190 | if $self->has_parent; |
e27dfc11 |
191 | |
3726f905 |
192 | return $self->_compile_type($check); |
193 | } |
194 | |
195 | sub _compile_hand_optimized_type_constraint { |
196 | my $self = shift; |
e27dfc11 |
197 | |
3726f905 |
198 | my $type_constraint = $self->hand_optimized_type_constraint; |
e27dfc11 |
199 | |
70ea9161 |
200 | unless ( ref $type_constraint ) { |
201 | require Moose; |
202 | Carp::confess ("Hand optimized type constraint for " . $self->name . " is not a code reference"); |
203 | Moose->throw_error("Hand optimized type constraint is not a code reference"); |
204 | } |
42bc21a4 |
205 | |
206 | return $type_constraint; |
3726f905 |
207 | } |
208 | |
209 | sub _compile_subtype { |
210 | my ($self, $check) = @_; |
e27dfc11 |
211 | |
baf26cc6 |
212 | # gather all the parent constraintss in order |
3726f905 |
213 | my @parents; |
baf26cc6 |
214 | my $optimized_parent; |
3726f905 |
215 | foreach my $parent ($self->_collect_all_parents) { |
baf26cc6 |
216 | # if a parent is optimized, the optimized constraint already includes |
217 | # all of its parents tcs, so we can break the loop |
3726f905 |
218 | if ($parent->has_hand_optimized_type_constraint) { |
baf26cc6 |
219 | push @parents => $optimized_parent = $parent->hand_optimized_type_constraint; |
e27dfc11 |
220 | last; |
3726f905 |
221 | } |
222 | else { |
baf26cc6 |
223 | push @parents => $parent->constraint; |
3726f905 |
224 | } |
225 | } |
e27dfc11 |
226 | |
baf26cc6 |
227 | @parents = grep { $_ != $null_constraint } reverse @parents; |
228 | |
229 | unless ( @parents ) { |
230 | return $self->_compile_type($check); |
231 | } elsif( $optimized_parent and @parents == 1 ) { |
232 | # the case of just one optimized parent is optimized to prevent |
233 | # looping and the unnecessary localization |
b5981f07 |
234 | if ( $check == $null_constraint ) { |
235 | return $optimized_parent; |
236 | } else { |
237 | return Class::MOP::subname($self->name, sub { |
238 | return undef unless $optimized_parent->($_[0]); |
a1257460 |
239 | my (@args) = @_; |
240 | local $_ = $args[0]; |
241 | $check->(@args); |
b5981f07 |
242 | }); |
243 | } |
baf26cc6 |
244 | } else { |
245 | # general case, check all the constraints, from the first parent to ourselves |
b5981f07 |
246 | my @checks = @parents; |
247 | push @checks, $check if $check != $null_constraint; |
baf26cc6 |
248 | return Class::MOP::subname($self->name => sub { |
a1257460 |
249 | my (@args) = @_; |
250 | local $_ = $args[0]; |
baf26cc6 |
251 | foreach my $check (@checks) { |
a1257460 |
252 | return undef unless $check->(@args); |
baf26cc6 |
253 | } |
254 | return 1; |
255 | }); |
256 | } |
3726f905 |
257 | } |
258 | |
259 | sub _compile_type { |
260 | my ($self, $check) = @_; |
baf26cc6 |
261 | |
262 | return $check if $check == $null_constraint; # Item, Any |
263 | |
1b2aea39 |
264 | return Class::MOP::subname($self->name => sub { |
a1257460 |
265 | my (@args) = @_; |
266 | local $_ = $args[0]; |
267 | $check->(@args); |
1b2aea39 |
268 | }); |
3726f905 |
269 | } |
270 | |
271 | ## other utils ... |
272 | |
273 | sub _collect_all_parents { |
274 | my $self = shift; |
275 | my @parents; |
276 | my $current = $self->parent; |
277 | while (defined $current) { |
278 | push @parents => $current; |
279 | $current = $current->parent; |
280 | } |
281 | return @parents; |
282 | } |
283 | |
85a9908f |
284 | sub create_child_type { |
9ceb576e |
285 | my ($self, %opts) = @_; |
286 | my $class = ref $self; |
287 | return $class->new(%opts, parent => $self); |
288 | } |
289 | |
4e036ee4 |
290 | 1; |
291 | |
292 | __END__ |
293 | |
294 | =pod |
295 | |
296 | =head1 NAME |
297 | |
6ba6d68c |
298 | Moose::Meta::TypeConstraint - The Moose Type Constraint metaclass |
4e036ee4 |
299 | |
300 | =head1 DESCRIPTION |
301 | |
cfd006f0 |
302 | This class represents a single type constraint. Moose's built-in type |
303 | constraints, as well as constraints you define, are all store in a |
304 | L<Moose::Meta::TypeConstraint::Registry> object as objects of this |
305 | class. |
6ba6d68c |
306 | |
baf46b9e |
307 | =head1 INHERITANCE |
308 | |
309 | C<Moose::Meta::TypeConstraint> is a subclass of L<Class::MOP::Object>. |
310 | |
4e036ee4 |
311 | =head1 METHODS |
312 | |
313 | =over 4 |
314 | |
cfd006f0 |
315 | =item B<< Moose::Meta::TypeConstraint->new(%options) >> |
4e036ee4 |
316 | |
cfd006f0 |
317 | This creates a new type constraint based on the provided C<%options>: |
4e036ee4 |
318 | |
cfd006f0 |
319 | =over 8 |
d9e17f80 |
320 | |
cfd006f0 |
321 | =item * name |
e606ae5f |
322 | |
cfd006f0 |
323 | The constraint name. If a name is not provided, it will be set to |
324 | "__ANON__". |
b26e162e |
325 | |
cfd006f0 |
326 | =item * parent |
b26e162e |
327 | |
cfd006f0 |
328 | A C<Moose::Meta::TypeConstraint> object which is the parent type for |
329 | the type being created. This is optional. |
cce8198b |
330 | |
cfd006f0 |
331 | =item * constraint |
e606ae5f |
332 | |
cfd006f0 |
333 | This is the subroutine reference that implements the actual constraint |
334 | check. This defaults to a subroutine which always returns true. |
6ba6d68c |
335 | |
cfd006f0 |
336 | =item * message |
0a5bd159 |
337 | |
cfd006f0 |
338 | A subroutine reference which is used to generate an error message when |
339 | the constraint fails. This is optional. |
0a5bd159 |
340 | |
cfd006f0 |
341 | =item * coercion |
76d37e5a |
342 | |
cfd006f0 |
343 | A L<Moose::Meta::TypeCoercion> object representing the coercions to |
344 | the type. This is optional. |
76d37e5a |
345 | |
cfd006f0 |
346 | =item * optimized |
76d37e5a |
347 | |
cfd006f0 |
348 | This is a variant of the C<constraint> parameter that is somehow |
349 | optimized. Typically, this means incorporating both the type's |
350 | constraint and all of its parents' constraints into a single |
351 | subroutine reference. |
6ba6d68c |
352 | |
cfd006f0 |
353 | =back |
4e036ee4 |
354 | |
cfd006f0 |
355 | =item B<< $constraint->equals($type_name_or_object) >> |
e606ae5f |
356 | |
cfd006f0 |
357 | Returns true if the supplied name or type object is the same as the |
358 | current type. |
66811d63 |
359 | |
cfd006f0 |
360 | =item B<< $constraint->is_subtype_of($type_name_or_object) >> |
e606ae5f |
361 | |
cfd006f0 |
362 | Returns true if the supplied name or type object is a parent of the |
363 | current type. |
3726f905 |
364 | |
cfd006f0 |
365 | =item B<< $constraint->is_a_type_of($type_name_or_object) >> |
e606ae5f |
366 | |
cfd006f0 |
367 | Returns true if the given type is the same as the current type, or is |
368 | a parent of the current type. This is a shortcut for checking |
369 | C<equals> and C<is_subtype_of>. |
d9e17f80 |
370 | |
cfd006f0 |
371 | =item B<< $constraint->coerce($value) >> |
2f7e4042 |
372 | |
cfd006f0 |
373 | This will attempt to coerce the value to the type. If the type does |
374 | have any defined coercions this will throw an error. |
66811d63 |
375 | |
cfd006f0 |
376 | =item B<< $constraint->check($value) >> |
2f7e4042 |
377 | |
cfd006f0 |
378 | Returns true if the given value passes the constraint for the type. |
76d37e5a |
379 | |
cfd006f0 |
380 | =item B<< $constraint->validate($value) >> |
2f7e4042 |
381 | |
cfd006f0 |
382 | This is similar to C<check>. However, if the type I<is valid> then the |
383 | method returns an explicit C<undef>. If the type is not valid, we call |
384 | C<< $self->get_message($value) >> internally to generate an error |
385 | message. |
76d37e5a |
386 | |
cfd006f0 |
387 | =item B<< $constraint->name >> |
2f7e4042 |
388 | |
cfd006f0 |
389 | Returns the type's name, as provided to the constructor. |
688fcdda |
390 | |
cfd006f0 |
391 | =item B<< $constraint->parent >> |
2f7e4042 |
392 | |
cfd006f0 |
393 | Returns the type's parent, as provided to the constructor, if any. |
4e036ee4 |
394 | |
cfd006f0 |
395 | =item B<< $constraint->has_parent >> |
2f7e4042 |
396 | |
cfd006f0 |
397 | Returns true if the type has a parent type. |
a27aa600 |
398 | |
cfd006f0 |
399 | =item B<< $constraint->parents >> |
2f7e4042 |
400 | |
cfd006f0 |
401 | A synonym for C<parent>. This is useful for polymorphism with types |
402 | that can have more than one parent. |
c8cf9aaa |
403 | |
cfd006f0 |
404 | =item B<< $constraint->constraint >> |
c8cf9aaa |
405 | |
cfd006f0 |
406 | Returns the type's constraint, as provided to the constructor. |
9ceb576e |
407 | |
cfd006f0 |
408 | =item B<< $constraint->get_message($value) >> |
4e036ee4 |
409 | |
cfd006f0 |
410 | This generates a method for the given value. If the type does not have |
411 | an explicit message, we generate a default message. |
3726f905 |
412 | |
cfd006f0 |
413 | =item B<< $constraint->has_message >> |
414 | |
415 | Returns true if the type has a message. |
416 | |
417 | =item B<< $constraint->message >> |
418 | |
419 | Returns the type's message as a subroutine reference. |
420 | |
421 | =item B<< $constraint->coercion >> |
422 | |
423 | Returns the type's L<Moose::Meta::TypeCoercion> object, if one |
424 | exists. |
425 | |
426 | =item B<< $constraint->has_coercion >> |
427 | |
428 | Returns true if the type has a coercion. |
429 | |
430 | =item B<< $constraint->hand_optimized_type_constraint >> |
431 | |
432 | Returns the type's hand optimized constraint, as provided to the |
433 | constructor via the C<optimized> option. |
434 | |
435 | =item B<< $constraint->has_hand_optimized_type_constraint >> |
436 | |
437 | Returns true if the type has an optimized constraint. |
438 | |
439 | =item B<< $constraint->create_child_type(%options) >> |
451c8248 |
440 | |
cfd006f0 |
441 | This returns a new type constraint of the same class using the |
442 | provided C<%options>. The C<parent> option will be the current type. |
3726f905 |
443 | |
cfd006f0 |
444 | This method exists so that subclasses of this class can override this |
445 | behavior and change how child types are created. |
451c8248 |
446 | |
447 | =back |
448 | |
4e036ee4 |
449 | =head1 BUGS |
450 | |
e27dfc11 |
451 | All complex software has bugs lurking in it, and this module is no |
4e036ee4 |
452 | exception. If you find a bug please either email me, or add the bug |
453 | to cpan-RT. |
454 | |
455 | =head1 AUTHOR |
456 | |
457 | Stevan Little E<lt>stevan@iinteractive.comE<gt> |
458 | |
459 | =head1 COPYRIGHT AND LICENSE |
460 | |
2840a3b2 |
461 | Copyright 2006-2009 by Infinity Interactive, Inc. |
4e036ee4 |
462 | |
463 | L<http://www.iinteractive.com> |
464 | |
465 | This library is free software; you can redistribute it and/or modify |
e27dfc11 |
466 | it under the same terms as Perl itself. |
4e036ee4 |
467 | |
c8cf9aaa |
468 | =cut |