2 package Moose::Meta::TypeConstraint;
8 use overload '0+' => sub { refaddr(shift) }, # id an object
9 '""' => sub { shift->name }, # stringify to tc name
15 use Scalar::Util qw(blessed refaddr);
16 use Sub::Name qw(subname);
19 use base qw(Class::MOP::Object);
21 __PACKAGE__->meta->add_attribute('name' => (
23 Class::MOP::_definition_context(),
25 __PACKAGE__->meta->add_attribute('parent' => (
27 predicate => 'has_parent',
28 Class::MOP::_definition_context(),
31 my $null_constraint = sub { 1 };
32 __PACKAGE__->meta->add_attribute('constraint' => (
33 reader => 'constraint',
34 writer => '_set_constraint',
35 default => sub { $null_constraint },
36 Class::MOP::_definition_context(),
39 __PACKAGE__->meta->add_attribute('message' => (
40 accessor => 'message',
41 predicate => 'has_message',
42 Class::MOP::_definition_context(),
45 __PACKAGE__->meta->add_attribute('_default_message' => (
46 accessor => '_default_message',
47 Class::MOP::_definition_context(),
50 # can't make this a default because it has to close over the type name, and
51 # cmop attributes don't have lazy
52 my $_default_message_generator = sub {
56 # have to load it late like this, since it uses Moose itself
57 my $can_partialdump = try {
58 # versions prior to 0.14 had a potential infinite loop bug
59 Class::MOP::load_class('Devel::PartialDump', { -version => 0.14 });
62 if ($can_partialdump) {
63 $value = Devel::PartialDump->new->dump($value);
66 $value = (defined $value ? overload::StrVal($value) : 'undef');
68 return "Validation failed for '" . $name . "' with value $value";
71 __PACKAGE__->meta->add_attribute('coercion' => (
72 accessor => 'coercion',
73 predicate => 'has_coercion',
74 Class::MOP::_definition_context(),
77 __PACKAGE__->meta->add_attribute('hand_optimized_type_constraint' => (
78 init_arg => 'optimized',
79 accessor => 'hand_optimized_type_constraint',
80 predicate => 'has_hand_optimized_type_constraint',
81 Class::MOP::_definition_context(),
84 __PACKAGE__->meta->add_attribute('inlined' => (
85 init_arg => 'inlined',
86 accessor => 'inlined',
87 predicate => '_has_inlined_type_constraint',
88 Class::MOP::_definition_context(),
91 __PACKAGE__->meta->add_attribute('inline_environment' => (
92 init_arg => 'inline_environment',
93 accessor => '_inline_environment',
94 default => sub { {} },
95 Class::MOP::_definition_context(),
105 __PACKAGE__->meta->add_attribute('compiled_type_constraint' => (
106 accessor => '_compiled_type_constraint',
107 predicate => '_has_compiled_type_constraint',
108 Class::MOP::_definition_context(),
111 __PACKAGE__->meta->add_attribute('package_defined_in' => (
112 accessor => '_package_defined_in',
113 Class::MOP::_definition_context(),
118 my ($first, @rest) = @_;
119 my %args = ref $first ? %$first : $first ? ($first, @rest) : ();
120 $args{name} = $args{name} ? "$args{name}" : "__ANON__";
122 if ( $args{optimized} ) {
123 Moose::Deprecated::deprecated(
124 feature => 'optimized type constraint sub ref',
126 'Providing an optimized subroutine ref for type constraints is deprecated.'
127 . ' Use the inlining feature (inline_as) instead.'
131 if ( exists $args{message}
132 && (!ref($args{message}) || ref($args{message}) ne 'CODE') ) {
133 confess("The 'message' parameter must be a coderef");
136 my $self = $class->_new(%args);
137 $self->compile_type_constraint()
138 unless $self->_has_compiled_type_constraint;
139 $self->_default_message($_default_message_generator->($self->name))
140 unless $self->has_message;
149 my $coercion = $self->coercion;
153 Moose->throw_error("Cannot coerce without a type coercion");
156 return $_[0] if $self->check($_[0]);
158 return $coercion->coerce(@_);
164 my $coercion = $self->coercion;
168 Moose->throw_error("Cannot coerce without a type coercion");
171 return $_[0] if $self->check($_[0]);
173 my $result = $coercion->coerce(@_);
175 $self->assert_valid($result);
181 my ($self, @args) = @_;
182 my $constraint_subref = $self->_compiled_type_constraint;
183 return $constraint_subref->(@args) ? 1 : undef;
187 my ($self, $value) = @_;
188 if ($self->_compiled_type_constraint->($value)) {
192 $self->get_message($value);
199 if ( $self->has_parent && $self->constraint == $null_constraint ) {
200 return $self->parent->can_be_inlined;
203 return $self->_has_inlined_type_constraint;
209 unless ( $self->can_be_inlined ) {
211 Moose->throw_error( 'Cannot inline a type constraint check for ' . $self->name );
214 if ( $self->has_parent && $self->constraint == $null_constraint ) {
215 return $self->parent->_inline_check(@_);
218 return '( do { ' . $self->inlined->( $self, @_ ) . ' } )';
221 sub inline_environment {
224 if ( $self->has_parent && $self->constraint == $null_constraint ) {
225 return $self->parent->inline_environment;
228 return $self->_inline_environment;
232 my ($self, $value) = @_;
234 my $error = $self->validate($value);
235 return 1 if ! defined $error;
238 Moose->throw_error($error);
242 my ($self, $value) = @_;
243 my $msg = $self->has_message
245 : $self->_default_message;
247 return $msg->($value);
250 ## type predicates ...
253 my ( $self, $type_or_name ) = @_;
255 my $other = Moose::Util::TypeConstraints::find_type_constraint($type_or_name) or return;
257 return 1 if $self == $other;
259 if ( $self->has_hand_optimized_type_constraint and $other->has_hand_optimized_type_constraint ) {
260 return 1 if $self->hand_optimized_type_constraint == $other->hand_optimized_type_constraint;
263 return unless $self->constraint == $other->constraint;
265 if ( $self->has_parent ) {
266 return unless $other->has_parent;
267 return unless $self->parent->equals( $other->parent );
269 return if $other->has_parent;
276 my ($self, $type_or_name) = @_;
278 my $type = Moose::Util::TypeConstraints::find_type_constraint($type_or_name) or return;
280 ($self->equals($type) || $self->is_subtype_of($type));
284 my ($self, $type_or_name) = @_;
286 my $type = Moose::Util::TypeConstraints::find_type_constraint($type_or_name) or return;
290 while (my $parent = $current->parent) {
291 return 1 if $parent->equals($type);
298 ## compiling the type constraint
300 sub compile_type_constraint {
302 $self->_compiled_type_constraint($self->_actually_compile_type_constraint);
305 ## type compilers ...
307 sub _actually_compile_type_constraint {
310 return $self->_compile_hand_optimized_type_constraint
311 if $self->has_hand_optimized_type_constraint;
313 if ( $self->can_be_inlined ) {
315 source => 'sub { ' . $self->_inline_check('$_[0]') . ' }',
316 environment => $self->inline_environment,
320 my $check = $self->constraint;
321 unless ( defined $check ) {
323 Moose->throw_error( "Could not compile type constraint '"
325 . "' because no constraint check" );
328 return $self->_compile_subtype($check)
329 if $self->has_parent;
331 return $self->_compile_type($check);
334 sub _compile_hand_optimized_type_constraint {
337 my $type_constraint = $self->hand_optimized_type_constraint;
339 unless ( ref $type_constraint ) {
341 Moose->throw_error("Hand optimized type constraint is not a code reference");
344 return $type_constraint;
347 sub _compile_subtype {
348 my ($self, $check) = @_;
350 # gather all the parent constraintss in order
352 my $optimized_parent;
353 foreach my $parent ($self->_collect_all_parents) {
354 # if a parent is optimized, the optimized constraint already includes
355 # all of its parents tcs, so we can break the loop
356 if ($parent->has_hand_optimized_type_constraint) {
357 push @parents => $optimized_parent = $parent->hand_optimized_type_constraint;
361 push @parents => $parent->constraint;
365 @parents = grep { $_ != $null_constraint } reverse @parents;
367 unless ( @parents ) {
368 return $self->_compile_type($check);
369 } elsif( $optimized_parent and @parents == 1 ) {
370 # the case of just one optimized parent is optimized to prevent
371 # looping and the unnecessary localization
372 if ( $check == $null_constraint ) {
373 return $optimized_parent;
375 return subname($self->name, sub {
376 return undef unless $optimized_parent->($_[0]);
383 # general case, check all the constraints, from the first parent to ourselves
384 my @checks = @parents;
385 push @checks, $check if $check != $null_constraint;
386 return subname($self->name => sub {
389 foreach my $check (@checks) {
390 return undef unless $check->(@args);
398 my ($self, $check) = @_;
400 return $check if $check == $null_constraint; # Item, Any
402 return subname($self->name => sub {
411 sub _collect_all_parents {
414 my $current = $self->parent;
415 while (defined $current) {
416 push @parents => $current;
417 $current = $current->parent;
422 sub create_child_type {
423 my ($self, %opts) = @_;
424 my $class = ref $self;
425 return $class->new(%opts, parent => $self);
430 # ABSTRACT: The Moose Type Constraint metaclass
438 This class represents a single type constraint. Moose's built-in type
439 constraints, as well as constraints you define, are all stored in a
440 L<Moose::Meta::TypeConstraint::Registry> object as objects of this
445 C<Moose::Meta::TypeConstraint> is a subclass of L<Class::MOP::Object>.
451 =item B<< Moose::Meta::TypeConstraint->new(%options) >>
453 This creates a new type constraint based on the provided C<%options>:
459 The constraint name. If a name is not provided, it will be set to
464 A C<Moose::Meta::TypeConstraint> object which is the parent type for
465 the type being created. This is optional.
469 This is the subroutine reference that implements the actual constraint
470 check. This defaults to a subroutine which always returns true.
474 A subroutine reference which is used to generate an error message when
475 the constraint fails. This is optional.
479 A L<Moose::Meta::TypeCoercion> object representing the coercions to
480 the type. This is optional.
484 A subroutine which returns a string suitable for inlining this type
485 constraint. It will be called as a method on the type constraint object, and
486 will receive a single additional parameter, a variable name to be tested
487 (usually C<"$_"> or C<"$_[0]">.
491 =item * inline_environment
493 A hash reference of variables to close over. The keys are variables names, and
494 the values are I<references> to the variables.
498 B<This option is deprecated.>
500 This is a variant of the C<constraint> parameter that is somehow
501 optimized. Typically, this means incorporating both the type's
502 constraint and all of its parents' constraints into a single
503 subroutine reference.
507 =item B<< $constraint->equals($type_name_or_object) >>
509 Returns true if the supplied name or type object is the same as the
512 =item B<< $constraint->is_subtype_of($type_name_or_object) >>
514 Returns true if the supplied name or type object is a parent of the
517 =item B<< $constraint->is_a_type_of($type_name_or_object) >>
519 Returns true if the given type is the same as the current type, or is
520 a parent of the current type. This is a shortcut for checking
521 C<equals> and C<is_subtype_of>.
523 =item B<< $constraint->coerce($value) >>
525 This will attempt to coerce the value to the type. If the type does not
526 have any defined coercions this will throw an error.
528 If no coercion can produce a value matching C<$constraint>, the original
531 =item B<< $constraint->assert_coerce($value) >>
533 This method behaves just like C<coerce>, but if the result is not valid
534 according to C<$constraint>, an error is thrown.
536 =item B<< $constraint->check($value) >>
538 Returns true if the given value passes the constraint for the type.
540 =item B<< $constraint->validate($value) >>
542 This is similar to C<check>. However, if the type I<is valid> then the
543 method returns an explicit C<undef>. If the type is not valid, we call
544 C<< $self->get_message($value) >> internally to generate an error
547 =item B<< $constraint->assert_valid($value) >>
549 Like C<check> and C<validate>, this method checks whether C<$value> is
550 valid under the constraint. If it is, it will return true. If it is not,
551 an exception will be thrown with the results of
552 C<< $self->get_message($value) >>.
554 =item B<< $constraint->name >>
556 Returns the type's name, as provided to the constructor.
558 =item B<< $constraint->parent >>
560 Returns the type's parent, as provided to the constructor, if any.
562 =item B<< $constraint->has_parent >>
564 Returns true if the type has a parent type.
566 =item B<< $constraint->parents >>
568 A synonym for C<parent>. This is useful for polymorphism with types
569 that can have more than one parent.
571 =item B<< $constraint->constraint >>
573 Returns the type's constraint, as provided to the constructor.
575 =item B<< $constraint->get_message($value) >>
577 This generates a method for the given value. If the type does not have
578 an explicit message, we generate a default message.
580 =item B<< $constraint->has_message >>
582 Returns true if the type has a message.
584 =item B<< $constraint->message >>
586 Returns the type's message as a subroutine reference.
588 =item B<< $constraint->coercion >>
590 Returns the type's L<Moose::Meta::TypeCoercion> object, if one
593 =item B<< $constraint->has_coercion >>
595 Returns true if the type has a coercion.
597 =item B<< $constraint->can_be_inlined >>
599 Returns true if this type constraint can be inlined. A type constraint which
600 subtypes an inlinable constraint and does not add an additional constraint
601 "inherits" its parent type's inlining.
603 =item B<< $constraint->hand_optimized_type_constraint >>
605 B<This method is deprecated.>
607 Returns the type's hand optimized constraint, as provided to the
608 constructor via the C<optimized> option.
610 =item B<< $constraint->has_hand_optimized_type_constraint >>
612 B<This method is deprecated.>
614 Returns true if the type has an optimized constraint.
616 =item B<< $constraint->create_child_type(%options) >>
618 This returns a new type constraint of the same class using the
619 provided C<%options>. The C<parent> option will be the current type.
621 This method exists so that subclasses of this class can override this
622 behavior and change how child types are created.
628 See L<Moose/BUGS> for details on reporting bugs.