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); |
9f2230e9 |
12 | use Sub::Name qw(subname); |
66811d63 |
13 | |
e606ae5f |
14 | use base qw(Class::MOP::Object); |
15 | |
e6ab9ca5 |
16 | our $VERSION = '0.83'; |
e606ae5f |
17 | $VERSION = eval $VERSION; |
d44714be |
18 | our $AUTHORITY = 'cpan:STEVAN'; |
66811d63 |
19 | |
3726f905 |
20 | __PACKAGE__->meta->add_attribute('name' => (reader => 'name')); |
21 | __PACKAGE__->meta->add_attribute('parent' => ( |
22 | reader => 'parent', |
23 | predicate => 'has_parent', |
24 | )); |
baf26cc6 |
25 | |
26 | my $null_constraint = sub { 1 }; |
d67145ed |
27 | __PACKAGE__->meta->add_attribute('constraint' => ( |
8de73ff1 |
28 | reader => 'constraint', |
29 | writer => '_set_constraint', |
baf26cc6 |
30 | default => sub { $null_constraint } |
d67145ed |
31 | )); |
76d37e5a |
32 | __PACKAGE__->meta->add_attribute('message' => ( |
33 | accessor => 'message', |
34 | predicate => 'has_message' |
35 | )); |
a27aa600 |
36 | __PACKAGE__->meta->add_attribute('coercion' => ( |
37 | accessor => 'coercion', |
38 | predicate => 'has_coercion' |
39 | )); |
70ea9161 |
40 | |
c8cf9aaa |
41 | __PACKAGE__->meta->add_attribute('hand_optimized_type_constraint' => ( |
42 | init_arg => 'optimized', |
43 | accessor => 'hand_optimized_type_constraint', |
e27dfc11 |
44 | predicate => 'has_hand_optimized_type_constraint', |
c8cf9aaa |
45 | )); |
46 | |
bd72f3c8 |
47 | sub parents { |
48 | my $self; |
49 | $self->parent; |
50 | } |
51 | |
3726f905 |
52 | # private accessors |
53 | |
54 | __PACKAGE__->meta->add_attribute('compiled_type_constraint' => ( |
55 | accessor => '_compiled_type_constraint', |
56 | predicate => '_has_compiled_type_constraint' |
57 | )); |
22aed3c0 |
58 | __PACKAGE__->meta->add_attribute('package_defined_in' => ( |
59 | accessor => '_package_defined_in' |
60 | )); |
61 | |
e27dfc11 |
62 | sub new { |
a27aa600 |
63 | my $class = shift; |
8534c69a |
64 | my ($first, @rest) = @_; |
65 | my %args = ref $first ? %$first : $first ? ($first, @rest) : (); |
66 | $args{name} = $args{name} ? "$args{name}" : "__ANON__"; |
70ea9161 |
67 | |
8534c69a |
68 | my $self = $class->_new(%args); |
3726f905 |
69 | $self->compile_type_constraint() |
70 | unless $self->_has_compiled_type_constraint; |
66811d63 |
71 | return $self; |
72 | } |
73 | |
8534c69a |
74 | |
75 | |
70ea9161 |
76 | sub coerce { |
77 | my $self = shift; |
78 | |
79 | my $coercion = $self->coercion; |
80 | |
81 | unless ($coercion) { |
82 | require Moose; |
83 | Moose->throw_error("Cannot coerce without a type coercion"); |
84 | } |
85 | |
02679ba4 |
86 | return $_[0] if $self->check($_[0]); |
87 | |
70ea9161 |
88 | return $coercion->coerce(@_); |
89 | } |
a1257460 |
90 | |
91 | sub check { |
92 | my ($self, @args) = @_; |
93 | my $constraint_subref = $self->_compiled_type_constraint; |
94 | return $constraint_subref->(@args) ? 1 : undef; |
95 | } |
96 | |
e27dfc11 |
97 | sub validate { |
76d37e5a |
98 | my ($self, $value) = @_; |
99 | if ($self->_compiled_type_constraint->($value)) { |
100 | return undef; |
101 | } |
102 | else { |
688fcdda |
103 | $self->get_message($value); |
76d37e5a |
104 | } |
105 | } |
106 | |
688fcdda |
107 | sub get_message { |
108 | my ($self, $value) = @_; |
688fcdda |
109 | if (my $msg = $self->message) { |
110 | local $_ = $value; |
111 | return $msg->($value); |
112 | } |
113 | else { |
d03bd989 |
114 | $value = (defined $value ? overload::StrVal($value) : 'undef'); |
688fcdda |
115 | return "Validation failed for '" . $self->name . "' failed with value $value"; |
d03bd989 |
116 | } |
688fcdda |
117 | } |
118 | |
3726f905 |
119 | ## type predicates ... |
120 | |
d9e17f80 |
121 | sub equals { |
122 | my ( $self, $type_or_name ) = @_; |
123 | |
e606ae5f |
124 | my $other = Moose::Util::TypeConstraints::find_type_constraint($type_or_name) or return; |
dabed765 |
125 | |
126 | return 1 if refaddr($self) == refaddr($other); |
127 | |
128 | if ( $self->has_hand_optimized_type_constraint and $other->has_hand_optimized_type_constraint ) { |
129 | return 1 if $self->hand_optimized_type_constraint == $other->hand_optimized_type_constraint; |
130 | } |
131 | |
132 | return unless $self->constraint == $other->constraint; |
133 | |
134 | if ( $self->has_parent ) { |
135 | return unless $other->has_parent; |
136 | return unless $self->parent->equals( $other->parent ); |
137 | } else { |
138 | return if $other->has_parent; |
139 | } |
d9e17f80 |
140 | |
dabed765 |
141 | return 1; |
d9e17f80 |
142 | } |
143 | |
b26e162e |
144 | sub is_a_type_of { |
d9e17f80 |
145 | my ($self, $type_or_name) = @_; |
146 | |
e606ae5f |
147 | my $type = Moose::Util::TypeConstraints::find_type_constraint($type_or_name) or return; |
d9e17f80 |
148 | |
149 | ($self->equals($type) || $self->is_subtype_of($type)); |
b26e162e |
150 | } |
151 | |
cce8198b |
152 | sub is_subtype_of { |
d9e17f80 |
153 | my ($self, $type_or_name) = @_; |
154 | |
e606ae5f |
155 | my $type = Moose::Util::TypeConstraints::find_type_constraint($type_or_name) or return; |
d9e17f80 |
156 | |
cce8198b |
157 | my $current = $self; |
d9e17f80 |
158 | |
cce8198b |
159 | while (my $parent = $current->parent) { |
d9e17f80 |
160 | return 1 if $parent->equals($type); |
cce8198b |
161 | $current = $parent; |
162 | } |
d9e17f80 |
163 | |
cce8198b |
164 | return 0; |
165 | } |
166 | |
3726f905 |
167 | ## compiling the type constraint |
168 | |
169 | sub compile_type_constraint { |
170 | my $self = shift; |
171 | $self->_compiled_type_constraint($self->_actually_compile_type_constraint); |
451c8248 |
172 | } |
173 | |
3726f905 |
174 | ## type compilers ... |
175 | |
176 | sub _actually_compile_type_constraint { |
177 | my $self = shift; |
e27dfc11 |
178 | |
3726f905 |
179 | return $self->_compile_hand_optimized_type_constraint |
180 | if $self->has_hand_optimized_type_constraint; |
e27dfc11 |
181 | |
3726f905 |
182 | my $check = $self->constraint; |
70ea9161 |
183 | unless ( defined $check ) { |
184 | require Moose; |
185 | Moose->throw_error( "Could not compile type constraint '" |
e27dfc11 |
186 | . $self->name |
70ea9161 |
187 | . "' because no constraint check" ); |
188 | } |
e27dfc11 |
189 | |
3726f905 |
190 | return $self->_compile_subtype($check) |
191 | if $self->has_parent; |
e27dfc11 |
192 | |
3726f905 |
193 | return $self->_compile_type($check); |
194 | } |
195 | |
196 | sub _compile_hand_optimized_type_constraint { |
197 | my $self = shift; |
e27dfc11 |
198 | |
3726f905 |
199 | my $type_constraint = $self->hand_optimized_type_constraint; |
e27dfc11 |
200 | |
70ea9161 |
201 | unless ( ref $type_constraint ) { |
202 | require Moose; |
203 | Carp::confess ("Hand optimized type constraint for " . $self->name . " is not a code reference"); |
204 | Moose->throw_error("Hand optimized type constraint is not a code reference"); |
205 | } |
42bc21a4 |
206 | |
207 | return $type_constraint; |
3726f905 |
208 | } |
209 | |
210 | sub _compile_subtype { |
211 | my ($self, $check) = @_; |
e27dfc11 |
212 | |
baf26cc6 |
213 | # gather all the parent constraintss in order |
3726f905 |
214 | my @parents; |
baf26cc6 |
215 | my $optimized_parent; |
3726f905 |
216 | foreach my $parent ($self->_collect_all_parents) { |
baf26cc6 |
217 | # if a parent is optimized, the optimized constraint already includes |
218 | # all of its parents tcs, so we can break the loop |
3726f905 |
219 | if ($parent->has_hand_optimized_type_constraint) { |
baf26cc6 |
220 | push @parents => $optimized_parent = $parent->hand_optimized_type_constraint; |
e27dfc11 |
221 | last; |
3726f905 |
222 | } |
223 | else { |
baf26cc6 |
224 | push @parents => $parent->constraint; |
3726f905 |
225 | } |
226 | } |
e27dfc11 |
227 | |
baf26cc6 |
228 | @parents = grep { $_ != $null_constraint } reverse @parents; |
229 | |
230 | unless ( @parents ) { |
231 | return $self->_compile_type($check); |
232 | } elsif( $optimized_parent and @parents == 1 ) { |
233 | # the case of just one optimized parent is optimized to prevent |
234 | # looping and the unnecessary localization |
b5981f07 |
235 | if ( $check == $null_constraint ) { |
236 | return $optimized_parent; |
237 | } else { |
9f2230e9 |
238 | return subname($self->name, sub { |
b5981f07 |
239 | return undef unless $optimized_parent->($_[0]); |
a1257460 |
240 | my (@args) = @_; |
241 | local $_ = $args[0]; |
242 | $check->(@args); |
b5981f07 |
243 | }); |
244 | } |
baf26cc6 |
245 | } else { |
246 | # general case, check all the constraints, from the first parent to ourselves |
b5981f07 |
247 | my @checks = @parents; |
248 | push @checks, $check if $check != $null_constraint; |
9f2230e9 |
249 | return subname($self->name => sub { |
a1257460 |
250 | my (@args) = @_; |
251 | local $_ = $args[0]; |
baf26cc6 |
252 | foreach my $check (@checks) { |
a1257460 |
253 | return undef unless $check->(@args); |
baf26cc6 |
254 | } |
255 | return 1; |
256 | }); |
257 | } |
3726f905 |
258 | } |
259 | |
260 | sub _compile_type { |
261 | my ($self, $check) = @_; |
baf26cc6 |
262 | |
263 | return $check if $check == $null_constraint; # Item, Any |
264 | |
9f2230e9 |
265 | return subname($self->name => sub { |
a1257460 |
266 | my (@args) = @_; |
267 | local $_ = $args[0]; |
268 | $check->(@args); |
1b2aea39 |
269 | }); |
3726f905 |
270 | } |
271 | |
272 | ## other utils ... |
273 | |
274 | sub _collect_all_parents { |
275 | my $self = shift; |
276 | my @parents; |
277 | my $current = $self->parent; |
278 | while (defined $current) { |
279 | push @parents => $current; |
280 | $current = $current->parent; |
281 | } |
282 | return @parents; |
283 | } |
284 | |
85a9908f |
285 | sub create_child_type { |
9ceb576e |
286 | my ($self, %opts) = @_; |
287 | my $class = ref $self; |
288 | return $class->new(%opts, parent => $self); |
289 | } |
290 | |
4e036ee4 |
291 | 1; |
292 | |
293 | __END__ |
294 | |
295 | =pod |
296 | |
297 | =head1 NAME |
298 | |
6ba6d68c |
299 | Moose::Meta::TypeConstraint - The Moose Type Constraint metaclass |
4e036ee4 |
300 | |
301 | =head1 DESCRIPTION |
302 | |
cfd006f0 |
303 | This class represents a single type constraint. Moose's built-in type |
304 | constraints, as well as constraints you define, are all store in a |
305 | L<Moose::Meta::TypeConstraint::Registry> object as objects of this |
306 | class. |
6ba6d68c |
307 | |
baf46b9e |
308 | =head1 INHERITANCE |
309 | |
310 | C<Moose::Meta::TypeConstraint> is a subclass of L<Class::MOP::Object>. |
311 | |
4e036ee4 |
312 | =head1 METHODS |
313 | |
314 | =over 4 |
315 | |
cfd006f0 |
316 | =item B<< Moose::Meta::TypeConstraint->new(%options) >> |
4e036ee4 |
317 | |
cfd006f0 |
318 | This creates a new type constraint based on the provided C<%options>: |
4e036ee4 |
319 | |
cfd006f0 |
320 | =over 8 |
d9e17f80 |
321 | |
cfd006f0 |
322 | =item * name |
e606ae5f |
323 | |
cfd006f0 |
324 | The constraint name. If a name is not provided, it will be set to |
325 | "__ANON__". |
b26e162e |
326 | |
cfd006f0 |
327 | =item * parent |
b26e162e |
328 | |
cfd006f0 |
329 | A C<Moose::Meta::TypeConstraint> object which is the parent type for |
330 | the type being created. This is optional. |
cce8198b |
331 | |
cfd006f0 |
332 | =item * constraint |
e606ae5f |
333 | |
cfd006f0 |
334 | This is the subroutine reference that implements the actual constraint |
335 | check. This defaults to a subroutine which always returns true. |
6ba6d68c |
336 | |
cfd006f0 |
337 | =item * message |
0a5bd159 |
338 | |
cfd006f0 |
339 | A subroutine reference which is used to generate an error message when |
340 | the constraint fails. This is optional. |
0a5bd159 |
341 | |
cfd006f0 |
342 | =item * coercion |
76d37e5a |
343 | |
cfd006f0 |
344 | A L<Moose::Meta::TypeCoercion> object representing the coercions to |
345 | the type. This is optional. |
76d37e5a |
346 | |
cfd006f0 |
347 | =item * optimized |
76d37e5a |
348 | |
cfd006f0 |
349 | This is a variant of the C<constraint> parameter that is somehow |
350 | optimized. Typically, this means incorporating both the type's |
351 | constraint and all of its parents' constraints into a single |
352 | subroutine reference. |
6ba6d68c |
353 | |
cfd006f0 |
354 | =back |
4e036ee4 |
355 | |
cfd006f0 |
356 | =item B<< $constraint->equals($type_name_or_object) >> |
e606ae5f |
357 | |
cfd006f0 |
358 | Returns true if the supplied name or type object is the same as the |
359 | current type. |
66811d63 |
360 | |
cfd006f0 |
361 | =item B<< $constraint->is_subtype_of($type_name_or_object) >> |
e606ae5f |
362 | |
cfd006f0 |
363 | Returns true if the supplied name or type object is a parent of the |
364 | current type. |
3726f905 |
365 | |
cfd006f0 |
366 | =item B<< $constraint->is_a_type_of($type_name_or_object) >> |
e606ae5f |
367 | |
cfd006f0 |
368 | Returns true if the given type is the same as the current type, or is |
369 | a parent of the current type. This is a shortcut for checking |
370 | C<equals> and C<is_subtype_of>. |
d9e17f80 |
371 | |
cfd006f0 |
372 | =item B<< $constraint->coerce($value) >> |
2f7e4042 |
373 | |
cfd006f0 |
374 | This will attempt to coerce the value to the type. If the type does |
375 | have any defined coercions this will throw an error. |
66811d63 |
376 | |
cfd006f0 |
377 | =item B<< $constraint->check($value) >> |
2f7e4042 |
378 | |
cfd006f0 |
379 | Returns true if the given value passes the constraint for the type. |
76d37e5a |
380 | |
cfd006f0 |
381 | =item B<< $constraint->validate($value) >> |
2f7e4042 |
382 | |
cfd006f0 |
383 | This is similar to C<check>. However, if the type I<is valid> then the |
384 | method returns an explicit C<undef>. If the type is not valid, we call |
385 | C<< $self->get_message($value) >> internally to generate an error |
386 | message. |
76d37e5a |
387 | |
cfd006f0 |
388 | =item B<< $constraint->name >> |
2f7e4042 |
389 | |
cfd006f0 |
390 | Returns the type's name, as provided to the constructor. |
688fcdda |
391 | |
cfd006f0 |
392 | =item B<< $constraint->parent >> |
2f7e4042 |
393 | |
cfd006f0 |
394 | Returns the type's parent, as provided to the constructor, if any. |
4e036ee4 |
395 | |
cfd006f0 |
396 | =item B<< $constraint->has_parent >> |
2f7e4042 |
397 | |
cfd006f0 |
398 | Returns true if the type has a parent type. |
a27aa600 |
399 | |
cfd006f0 |
400 | =item B<< $constraint->parents >> |
2f7e4042 |
401 | |
cfd006f0 |
402 | A synonym for C<parent>. This is useful for polymorphism with types |
403 | that can have more than one parent. |
c8cf9aaa |
404 | |
cfd006f0 |
405 | =item B<< $constraint->constraint >> |
c8cf9aaa |
406 | |
cfd006f0 |
407 | Returns the type's constraint, as provided to the constructor. |
9ceb576e |
408 | |
cfd006f0 |
409 | =item B<< $constraint->get_message($value) >> |
4e036ee4 |
410 | |
cfd006f0 |
411 | This generates a method for the given value. If the type does not have |
412 | an explicit message, we generate a default message. |
3726f905 |
413 | |
cfd006f0 |
414 | =item B<< $constraint->has_message >> |
415 | |
416 | Returns true if the type has a message. |
417 | |
418 | =item B<< $constraint->message >> |
419 | |
420 | Returns the type's message as a subroutine reference. |
421 | |
422 | =item B<< $constraint->coercion >> |
423 | |
424 | Returns the type's L<Moose::Meta::TypeCoercion> object, if one |
425 | exists. |
426 | |
427 | =item B<< $constraint->has_coercion >> |
428 | |
429 | Returns true if the type has a coercion. |
430 | |
431 | =item B<< $constraint->hand_optimized_type_constraint >> |
432 | |
433 | Returns the type's hand optimized constraint, as provided to the |
434 | constructor via the C<optimized> option. |
435 | |
436 | =item B<< $constraint->has_hand_optimized_type_constraint >> |
437 | |
438 | Returns true if the type has an optimized constraint. |
439 | |
440 | =item B<< $constraint->create_child_type(%options) >> |
451c8248 |
441 | |
cfd006f0 |
442 | This returns a new type constraint of the same class using the |
443 | provided C<%options>. The C<parent> option will be the current type. |
3726f905 |
444 | |
cfd006f0 |
445 | This method exists so that subclasses of this class can override this |
446 | behavior and change how child types are created. |
451c8248 |
447 | |
448 | =back |
449 | |
4e036ee4 |
450 | =head1 BUGS |
451 | |
e27dfc11 |
452 | All complex software has bugs lurking in it, and this module is no |
4e036ee4 |
453 | exception. If you find a bug please either email me, or add the bug |
454 | to cpan-RT. |
455 | |
456 | =head1 AUTHOR |
457 | |
458 | Stevan Little E<lt>stevan@iinteractive.comE<gt> |
459 | |
460 | =head1 COPYRIGHT AND LICENSE |
461 | |
2840a3b2 |
462 | Copyright 2006-2009 by Infinity Interactive, Inc. |
4e036ee4 |
463 | |
464 | L<http://www.iinteractive.com> |
465 | |
466 | This library is free software; you can redistribute it and/or modify |
e27dfc11 |
467 | it under the same terms as Perl itself. |
4e036ee4 |
468 | |
c8cf9aaa |
469 | =cut |