-
-package # hide the package from PAUSE
- ArrayBasedStorage::Attribute;
-
-use strict;
-use warnings;
-
-use Carp 'confess';
-
-our $VERSION = '0.01';
-
-use base 'Class::MOP::Attribute';
-
-sub generate_accessor_method {
- my $self = shift;
- my $attr_name = $self->name;
- return sub {
- my $meta_instance = $_[0]->meta->get_meta_instance;
- $meta_instance->set_slot_value($_[0], $attr_name, $_[1]) if scalar(@_) == 2;
- $meta_instance->get_slot_value($_[0], $attr_name);
- };
-}
-
-sub generate_reader_method {
- my $self = shift;
- my $attr_name = $self->name;
- return sub {
- confess "Cannot assign a value to a read-only accessor" if @_ > 1;
- $_[0]->meta
- ->get_meta_instance
- ->get_slot_value($_[0], $attr_name);
- };
-}
-
-sub generate_writer_method {
- my $self = shift;
- my $attr_name = $self->name;
- return sub {
- $_[0]->meta
- ->get_meta_instance
- ->set_slot_value($_[0], $attr_name, $_[1]);
- };
-}
-
-sub generate_predicate_method {
- my $self = shift;
- my $attr_name = $self->name;
- return sub {
- defined $_[0]->meta
- ->get_meta_instance
- ->get_slot_value($_[0], $attr_name) ? 1 : 0;
- };
-}
-
+
package # hide the package from PAUSE
ArrayBasedStorage::Instance;
use strict;
use warnings;
+use Scalar::Util qw/refaddr/;
use Carp 'confess';
our $VERSION = '0.01';
+my $unbound = \'empty-slot-value';
use base 'Class::MOP::Instance';
my ($class, $meta, @attrs) = @_;
my $self = $class->SUPER::new($meta, @attrs);
my $index = 0;
- $self->{slot_index_map} = { map { $_ => $index++ } $self->get_all_slots };
+ $self->{'slot_index_map'} = { map { $_ => $index++ } $self->get_all_slots };
return $self;
}
sub create_instance {
my $self = shift;
- $self->bless_instance_structure([]);
+ my $instance = bless [], $self->_class_name;
+ $self->initialize_all_slots($instance);
+ return $instance;
+}
+
+sub clone_instance {
+ my ($self, $instance) = shift;
+ $self->bless_instance_structure([ @$instance ]);
}
# operations on meta instance
+sub get_slot_index_map { (shift)->{'slot_index_map'} }
+
+sub initialize_slot {
+ my ($self, $instance, $slot_name) = @_;
+ $self->set_slot_value($instance, $slot_name, $unbound);
+}
+
+sub deinitialize_slot {
+ my ( $self, $instance, $slot_name ) = @_;
+ $self->set_slot_value($instance, $slot_name, $unbound);
+}
+
sub get_all_slots {
my $self = shift;
- return sort @{$self->{slots}};
+ return sort $self->SUPER::get_all_slots;
}
sub get_slot_value {
my ($self, $instance, $slot_name) = @_;
- return $instance->[ $self->{slot_index_map}->{$slot_name} ];
+ my $value = $instance->[ $self->{'slot_index_map'}->{$slot_name} ];
+ return $value unless ref $value;
+ refaddr $value eq refaddr $unbound ? undef : $value;
}
sub set_slot_value {
my ($self, $instance, $slot_name, $value) = @_;
- $instance->[ $self->{slot_index_map}->{$slot_name} ] = $value;
+ $instance->[ $self->{'slot_index_map'}->{$slot_name} ] = $value;
}
-sub initialize_slot {
+sub is_slot_initialized {
my ($self, $instance, $slot_name) = @_;
- $instance->[ $self->{slot_index_map}->{$slot_name} ] = undef;
+ # NOTE: maybe use CLOS's *special-unbound-value* for this?
+ my $value = $instance->[ $self->{'slot_index_map'}->{$slot_name} ];
+ return 1 unless ref $value;
+ refaddr $value eq refaddr $unbound ? 0 : 1;
}
-sub is_slot_initialized {
- # NOTE:
- # maybe use CLOS's *special-unbound-value*
- # for this ?
- confess "Cannot really tell this for sure";
-}
+sub is_dependent_on_superclasses { 1 }
1;
package Foo;
- use metaclass 'Class::MOP::Class' => (
- ':attribute_metaclass' => 'ArrayBasedStorage::Attribute'
+ use metaclass (
':instance_metaclass' => 'ArrayBasedStorage::Instance'
);
This is a proof of concept using the Instance sub-protocol
which uses ARRAY refs to store the instance data.
-=head1 AUTHOR
+This is very similar now to the InsideOutClass example, and
+in fact, they both share the exact same test suite, with
+the only difference being the Instance metaclass they use.
+
+=head1 AUTHORS
Stevan Little E<lt>stevan@iinteractive.comE<gt>
+Yuval Kogman E<lt>nothingmuch@woobling.comE<gt>
+
=head1 SEE ALSO
=head1 COPYRIGHT AND LICENSE
-Copyright 2006 by Infinity Interactive, Inc.
+Copyright 2006-2008 by Infinity Interactive, Inc.
L<http://www.iinteractive.com>