use warnings;
use metaclass;
-our $VERSION = '0.57';
-$VERSION = eval $VERSION;
-our $AUTHORITY = 'cpan:STEVAN';
-
use base 'Moose::Meta::TypeConstraint';
+use Moose::Meta::TypeConstraint::Parameterized;
+use Moose::Util::TypeConstraints ();
__PACKAGE__->meta->add_attribute('constraint_generator' => (
accessor => 'constraint_generator',
sub generate_constraint_for {
my ($self, $type) = @_;
-
+
return unless $self->has_constraint_generator;
-
+
return $self->constraint_generator->($type->type_parameter)
if $type->is_subtype_of($self->name);
-
+
return $self->_can_coerce_constraint_from($type)
if $self->has_coercion
&& $self->coercion->has_coercion_for_type($type->parent->name);
-
+
return;
}
};
}
+sub _parse_type_parameter {
+ my ($self, $type_parameter) = @_;
+ return Moose::Util::TypeConstraints::find_or_create_isa_type_constraint($type_parameter);
+}
+
+sub parameterize {
+ my ($self, $type_parameter) = @_;
+
+ my $contained_tc = $self->_parse_type_parameter($type_parameter);
+
+ ## The type parameter should be a subtype of the parent's type parameter
+ ## if there is one.
+
+ if(my $parent = $self->parent) {
+ if($parent->can('type_parameter')) {
+ unless ( $contained_tc->is_a_type_of($parent->type_parameter) ) {
+ require Moose;
+ Moose->throw_error("$type_parameter is not a subtype of ".$parent->type_parameter);
+ }
+ }
+ }
+
+ if ( $contained_tc->isa('Moose::Meta::TypeConstraint') ) {
+ my $tc_name = $self->name . '[' . $contained_tc->name . ']';
+ return Moose::Meta::TypeConstraint::Parameterized->new(
+ name => $tc_name,
+ parent => $self,
+ type_parameter => $contained_tc,
+ );
+ }
+ else {
+ require Moose;
+ Moose->throw_error("The type parameter must be a Moose meta type");
+ }
+}
+
1;
+# ABSTRACT: Type constraints which can take a parameter (ArrayRef)
+
__END__
=pod
-=head1 NAME
+=head1 DESCRIPTION
-Moose::Meta::TypeConstraint::Parameterizable - Higher Order type constraints for Moose
+This class represents a parameterizable type constraint. This is a
+type constraint like C<ArrayRef> or C<HashRef>, that can be
+parameterized and made more specific by specifying a contained
+type. For example, instead of just an C<ArrayRef> of anything, you can
+specify that is an C<ArrayRef[Int]>.
-=head1 METHODS
-
-=over 4
-
-=item B<constraint_generator>
+A parameterizable constraint should not be used as an attribute type
+constraint. Instead, when parameterized it creates a
+L<Moose::Meta::TypeConstraint::Parameterized> which should be used.
-=item B<has_constraint_generator>
+=head1 INHERITANCE
-=item B<generate_constraint_for>
+C<Moose::Meta::TypeConstraint::Parameterizable> is a subclass of
+L<Moose::Meta::TypeConstraint>.
-=item B<meta>
+=head1 METHODS
-=back
+This class is intentionally not documented because the API is
+confusing and needs some work.
=head1 BUGS
-All complex software has bugs lurking in it, and this module is no
-exception. If you find a bug please either email me, or add the bug
-to cpan-RT.
-
-=head1 AUTHOR
-
-Stevan Little E<lt>stevan@iinteractive.comE<gt>
-
-=head1 COPYRIGHT AND LICENSE
-
-Copyright 2006-2008 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.
+See L<Moose/BUGS> for details on reporting bugs.
=cut