package Moose::Meta::TypeConstraint::Role;
use strict;
use warnings;
use metaclass;
use Scalar::Util 'blessed';
use Moose::Util::TypeConstraints ();
our $VERSION = '1.00';
$VERSION = eval $VERSION;
our $AUTHORITY = 'cpan:STEVAN';
use base 'Moose::Meta::TypeConstraint';
__PACKAGE__->meta->add_attribute('role' => (
reader => 'role',
));
sub new {
my ( $class, %args ) = @_;
$args{parent} = Moose::Util::TypeConstraints::find_type_constraint('Object');
my $self = $class->_new(\%args);
$self->_create_hand_optimized_type_constraint;
$self->compile_type_constraint();
return $self;
}
sub _create_hand_optimized_type_constraint {
my $self = shift;
my $role = $self->role;
$self->hand_optimized_type_constraint(
sub { Moose::Util::does_role($_[0], $role) }
);
}
sub parents {
my $self = shift;
return (
$self->parent,
map {
# FIXME find_type_constraint might find a TC named after the role but that isn't really it
# I did this anyway since it's a convention that preceded TypeConstraint::Role, and it should DWIM
# if anybody thinks this problematic please discuss on IRC.
# a possible fix is to add by attr indexing to the type registry to find types of a certain property
# regardless of their name
Moose::Util::TypeConstraints::find_type_constraint($_)
||
__PACKAGE__->new( role => $_, name => "__ANON__" )
} @{ Class::MOP::class_of($self->role)->get_roles },
);
}
sub equals {
my ( $self, $type_or_name ) = @_;
my $other = Moose::Util::TypeConstraints::find_type_constraint($type_or_name);
return unless defined $other;
return unless $other->isa(__PACKAGE__);
return $self->role eq $other->role;
}
sub is_a_type_of {
my ($self, $type_or_name) = @_;
my $type = Moose::Util::TypeConstraints::find_type_constraint($type_or_name);
($self->equals($type) || $self->is_subtype_of($type_or_name));
}
sub is_subtype_of {
my ($self, $type_or_name_or_role ) = @_;
if ( not ref $type_or_name_or_role ) {
# it might be a role
return 1 if Class::MOP::class_of($self->role)->does_role( $type_or_name_or_role );
}
my $type = Moose::Util::TypeConstraints::find_type_constraint($type_or_name_or_role);
return unless defined $type;
if ( $type->isa(__PACKAGE__) ) {
# if $type_or_name_or_role isn't a role, it might be the TC name of another ::Role type
# or it could also just be a type object in this branch
return Class::MOP::class_of($self->role)->does_role( $type->role );
} else {
# the only other thing we are a subtype of is Object
$self->SUPER::is_subtype_of($type);
}
}
sub create_child_type {
my ($self, @args) = @_;
return Moose::Meta::TypeConstraint->new(@args, parent => $self);
}
1;
__END__
=pod
=head1 NAME
Moose::Meta::TypeConstraint::Role - Role/TypeConstraint parallel hierarchy
=head1 DESCRIPTION
This class represents type constraints for a role.
=head1 INHERITANCE
C<Moose::Meta::TypeConstraint::Role> is a subclass of
L<Moose::Meta::TypeConstraint>.
=head1 METHODS
=over 4
=item B<< Moose::Meta::TypeConstraint::Role->new(%options) >>
This creates a new role type constraint based on the given
C<%options>.
It takes the same options as its parent, with two exceptions. First,
it requires an additional option, C<role>, which is name of the
constraint's role. Second, it automatically sets the parent to the
C<Object> type.
The constructor also overrides the hand optimized type constraint with
one it creates internally.
=item B<< $constraint->role >>
Returns the role name associated with the constraint.
=item B<< $constraint->parents >>
Returns all the type's parent types, corresponding to the roles that
its role does.
=item B<< $constraint->is_subtype_of($type_name_or_object) >>
If the given type is also a role type, then this checks that the
type's role does the other type's role.
Otherwise it falls back to the implementation in
L<Moose::Meta::TypeConstraint>.
=item B<< $constraint->create_child_type(%options) >>
This returns a new L<Moose::Meta::TypeConstraint> object with the type
as its parent.
Note that it does I<not> return a C<Moose::Meta::TypeConstraint::Role>
object!
=back
=head1 BUGS
See L<Moose/BUGS> for details on reporting bugs.
=head1 AUTHOR
Yuval Kogman E<lt>nothingmuch@cpan.orgE<gt>
=head1 COPYRIGHT AND LICENSE
Copyright 2006-2010 by Infinity Interactive, Inc.
L<http://www.iinteractive.com>
This library is free software; you can redistribute it and/or modify
it under the same terms as Perl itself.
=cut