2 package Moose::Meta::TypeCoercion;
8 use Moose::Meta::Attribute;
9 use Moose::Util::TypeConstraints ();
11 our $VERSION = '0.72';
12 $VERSION = eval $VERSION;
13 our $AUTHORITY = 'cpan:STEVAN';
15 __PACKAGE__->meta->add_attribute('type_coercion_map' => (
16 reader => 'type_coercion_map',
20 __PACKAGE__->meta->add_attribute(
21 Moose::Meta::Attribute->new('type_constraint' => (
22 reader => 'type_constraint',
28 __PACKAGE__->meta->add_attribute('compiled_type_coercion' => (
29 accessor => '_compiled_type_coercion'
34 my $self = $class->meta->new_object(@_);
35 $self->compile_type_coercion;
39 sub compile_type_coercion {
41 my @coercion_map = @{$self->type_coercion_map};
43 while (@coercion_map) {
44 my ($constraint_name, $action) = splice(@coercion_map, 0, 2);
45 my $type_constraint = ref $constraint_name ? $constraint_name : Moose::Util::TypeConstraints::find_or_parse_type_constraint($constraint_name);
47 unless ( defined $type_constraint ) {
49 Moose->throw_error("Could not find the type constraint ($constraint_name) to coerce from");
53 $type_constraint->_compiled_type_constraint,
57 $self->_compiled_type_coercion(sub {
59 foreach my $coercion (@coercions) {
60 my ($constraint, $converter) = @$coercion;
61 if ($constraint->($thing)) {
63 return $converter->($thing);
70 sub has_coercion_for_type {
71 my ($self, $type_name) = @_;
72 my %coercion_map = @{$self->type_coercion_map};
73 exists $coercion_map{$type_name} ? 1 : 0;
76 sub add_type_coercions {
77 my ($self, @new_coercion_map) = @_;
79 my $coercion_map = $self->type_coercion_map;
80 my %has_coercion = @$coercion_map;
82 while (@new_coercion_map) {
83 my ($constraint_name, $action) = splice(@new_coercion_map, 0, 2);
85 if ( exists $has_coercion{$constraint_name} ) {
87 Moose->throw_error("A coercion action already exists for '$constraint_name'")
90 push @{$coercion_map} => ($constraint_name, $action);
94 $self->compile_type_coercion;
97 sub coerce { $_[0]->_compiled_type_coercion->($_[1]) }
108 Moose::Meta::TypeCoercion - The Moose Type Coercion metaclass
112 For the most part, the only time you will ever encounter an
113 instance of this class is if you are doing some serious deep
114 introspection. This API should not be considered final, but
115 it is B<highly unlikely> that this will matter to a regular
118 If you wish to use features at this depth, please come to the
119 #moose IRC channel on irc.perl.org and we can talk :)
129 =item B<compile_type_coercion>
133 =item B<type_coercion_map>
135 =item B<type_constraint>
137 =item B<has_coercion_for_type>
139 =item B<add_type_coercions>
145 All complex software has bugs lurking in it, and this module is no
146 exception. If you find a bug please either email me, or add the bug
151 Stevan Little E<lt>stevan@iinteractive.comE<gt>
153 =head1 COPYRIGHT AND LICENSE
155 Copyright 2006-2009 by Infinity Interactive, Inc.
157 L<http://www.iinteractive.com>
159 This library is free software; you can redistribute it and/or modify
160 it under the same terms as Perl itself.