X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=examples%2FArrayBasedStorage.pod;h=bff9baaec231d2ea62041ea11e578135ca0c5e28;hb=41fc2d0fd29483cb704e06198bfaabbcd3e09d08;hp=bc5a19b9ddc87008b65f79c58db7b8dc835667d3;hpb=1a09d9cce4930577a39060a03029a32cd51d41c7;p=gitmo%2FClass-MOP.git

diff --git a/examples/ArrayBasedStorage.pod b/examples/ArrayBasedStorage.pod
index bc5a19b..bff9baa 100644
--- a/examples/ArrayBasedStorage.pod
+++ b/examples/ArrayBasedStorage.pod
@@ -4,10 +4,12 @@ package # hide the package from PAUSE
 
 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';
 
@@ -15,13 +17,15 @@ sub new {
     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 = $self->bless_instance_structure([]);
+    $self->initialize_all_slots($instance);
+    return $instance;
 }
 
 sub clone_instance {
@@ -31,7 +35,17 @@ sub clone_instance {
 
 # operations on meta instance
 
-sub get_slot_index_map { (shift)->{slot_index_map} }
+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;
@@ -40,21 +54,26 @@ sub 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 is_slot_initialized {
-    # NOTE:
-    # maybe use CLOS's *special-unbound-value*
-    # for this ?
-    confess "Cannot really tell this for sure";
+    my ($self, $instance, $slot_name) = @_;
+    # 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_dependent_on_superclasses { 1 }
+
 1;
 
 __END__
@@ -104,7 +123,7 @@ Yuval Kogman E<lt>nothingmuch@woobling.comE<gt>
 
 =head1 COPYRIGHT AND LICENSE
 
-Copyright 2006 by Infinity Interactive, Inc.
+Copyright 2006-2008 by Infinity Interactive, Inc.
 
 L<http://www.iinteractive.com>