2 package Moose::Meta::TypeConstraint::Union;
8 use Moose::Meta::TypeCoercion::Union;
10 use List::Util qw(first);
12 our $AUTHORITY = 'cpan:STEVAN';
14 use base 'Moose::Meta::TypeConstraint';
16 __PACKAGE__->meta->add_attribute('type_constraints' => (
17 accessor => 'type_constraints',
22 my ($class, %options) = @_;
24 my $name = join '|' => sort { $a cmp $b }
25 map { $_->name } @{ $options{type_constraints} };
27 my $self = $class->SUPER::new(
32 $self->_set_constraint(sub { $self->check($_[0]) });
37 # XXX - this is a rather gross implementation of laziness for the benefit of
38 # MX::Types. If we try to call ->has_coercion on the objects during object
39 # construction, this does not work when defining a recursive constraint with
44 return $self->{coercion} if exists $self->{coercion};
46 # Using any instead of grep here causes a weird error with some corner
47 # cases when MX::Types is in use. See RT #61001.
48 if ( grep { $_->has_coercion } @{ $self->type_constraints } ) {
49 return $self->{coercion} = Moose::Meta::TypeCoercion::Union->new(
50 type_constraint => $self );
53 return $self->{coercion} = undef;
58 return defined $_[0]->coercion;
61 sub _actually_compile_type_constraint {
64 my @constraints = @{ $self->type_constraints };
68 foreach my $type (@constraints) {
69 return 1 if $type->check($value);
77 my ( $self, $type_or_name ) = @_;
79 my $other = Moose::Util::TypeConstraints::find_type_constraint($type_or_name);
81 return unless $other->isa(__PACKAGE__);
83 my @self_constraints = @{ $self->type_constraints };
84 my @other_constraints = @{ $other->type_constraints };
86 return unless @self_constraints == @other_constraints;
88 # FIXME presort type constraints for efficiency?
89 constraint: foreach my $constraint ( @self_constraints ) {
90 for ( my $i = 0; $i < @other_constraints; $i++ ) {
91 if ( $constraint->equals($other_constraints[$i]) ) {
92 splice @other_constraints, $i, 1;
98 return @other_constraints == 0;
103 $self->type_constraints;
107 my ($self, $value) = @_;
109 foreach my $type (@{$self->type_constraints}) {
110 my $err = $type->validate($value);
111 return unless defined $err;
112 $message .= ($message ? ' and ' : '') . $err
115 return ($message . ' in (' . $self->name . ')') ;
119 my ($self, $value) = @_;
121 return first { $_->check($value) } @{ $self->type_constraints };
125 my ($self, $type_name) = @_;
126 foreach my $type (@{$self->type_constraints}) {
127 return 1 if $type->is_a_type_of($type_name);
133 my ($self, $type_name) = @_;
134 foreach my $type (@{$self->type_constraints}) {
135 return 1 if $type->is_subtype_of($type_name);
140 sub create_child_type {
141 my ( $self, %opts ) = @_;
144 = Moose::Meta::TypeConstraint->new( %opts, parent => $self );
146 # if we have a type constraint union, and no
147 # type check, this means we are just aliasing
148 # the union constraint, which means we need to
149 # handle this differently.
151 if ( not( defined $opts{constraint} )
152 && $self->has_coercion ) {
153 $constraint->coercion(
154 Moose::Meta::TypeCoercion::Union->new(
155 type_constraint => $self,
165 # ABSTRACT: A union of Moose type constraints
173 This metaclass represents a union of type constraints. A union takes
174 multiple type constraints, and is true if any one of its member
179 C<Moose::Meta::TypeConstraint::Union> is a subclass of
180 L<Moose::Meta::TypeConstraint>.
184 =item B<< Moose::Meta::TypeConstraint::Union->new(%options) >>
186 This creates a new class type constraint based on the given
189 It takes the same options as its parent. It also requires an
190 additional option, C<type_constraints>. This is an array reference
191 containing the L<Moose::Meta::TypeConstraint> objects that are the
192 members of the union type. The C<name> option defaults to the names
193 all of these member types sorted and then joined by a pipe (|).
195 The constructor sets the implementation of the constraint so that is
196 simply calls C<check> on the newly created object.
198 Finally, the constructor also makes sure that the object's C<coercion>
199 attribute is a L<Moose::Meta::TypeCoercion::Union> object.
201 =item B<< $constraint->type_constraints >>
203 This returns the array reference of C<type_constraints> provided to
206 =item B<< $constraint->parents >>
208 This returns the same constraint as the C<type_constraints> method.
210 =item B<< $constraint->check($value) >>
212 =item B<< $constraint->validate($value) >>
214 These two methods simply call the relevant method on each of the
215 member type constraints in the union. If any type accepts the value,
218 With C<validate> the error message returned includes all of the error
219 messages returned by the member type constraints.
221 =item B<< $constraint->equals($type_name_or_object) >>
223 A type is considered equal if it is also a union type, and the two
224 unions have the same member types.
226 =item B<< $constraint->find_type_for($value) >>
228 This returns the first member type constraint for which C<check($value)> is
229 true, allowing you to determine which of the Union's member type constraints
230 a given value matches.
232 =item B<< $constraint->is_a_type_of($type_name_or_object) >>
234 This returns true if any of the member type constraints return true
235 for the C<is_a_type_of> method.
237 =item B<< $constraint->is_subtype_of >>
239 This returns true if any of the member type constraints return true
240 for the C<is_a_subtype_of> method.
242 =item B<< $constraint->create_child_type(%options) >>
244 This returns a new L<Moose::Meta::TypeConstraint> object with the type
251 See L<Moose/BUGS> for details on reporting bugs.