ovidsbug

[gitmo/Moose.git] / lib / Moose / Meta / TypeCoercion.pm

diff --git a/lib/Moose/Meta/TypeCoercion.pm b/lib/Moose/Meta/TypeCoercion.pm
index 4decb47..aaae013 100644 (file)
--- a/lib/Moose/Meta/TypeCoercion.pm
+++ b/lib/Moose/Meta/TypeCoercion.pm
@@ -7,7 +7,90 @@ use metaclass;
 
 use Carp 'confess';
 
-our $VERSION = '0.01';
+use Moose::Meta::Attribute;
+use Moose::Util::TypeConstraints ();
+
+our $VERSION   = '0.06';
+our $AUTHORITY = 'cpan:STEVAN';
+
+__PACKAGE__->meta->add_attribute('type_coercion_map' => (
+    reader  => 'type_coercion_map',
+    default => sub { [] }
+));
+
+__PACKAGE__->meta->add_attribute(
+    Moose::Meta::Attribute->new('type_constraint' => (
+        reader   => 'type_constraint',
+        weak_ref => 1
+    ))
+);
+
+# private accessor
+__PACKAGE__->meta->add_attribute('compiled_type_coercion' => (
+    accessor => '_compiled_type_coercion'
+));
+
+sub new { 
+    my $class = shift;
+    my $self  = $class->meta->new_object(@_);
+    $self->compile_type_coercion;
+    return $self;
+}
+
+sub compile_type_coercion {
+    my $self = shift;
+    my @coercion_map = @{$self->type_coercion_map};
+    my @coercions;
+    while (@coercion_map) {
+        my ($constraint_name, $action) = splice(@coercion_map, 0, 2);
+        my $type_constraint = Moose::Util::TypeConstraints::find_or_create_type_constraint($constraint_name);
+        (defined $type_constraint)
+            || confess "Could not find the type constraint ($constraint_name) to coerce from";
+        push @coercions => [ 
+            $type_constraint->_compiled_type_constraint, 
+            $action 
+        ];
+    }
+    $self->_compiled_type_coercion(sub { 
+        my $thing = shift;
+        foreach my $coercion (@coercions) {
+            my ($constraint, $converter) = @$coercion;
+            if ($constraint->($thing)) {
+                local $_ = $thing;                
+                return $converter->($thing);
+            }
+        }
+        return $thing;
+    });    
+}
+
+sub has_coercion_for_type {
+    my ($self, $type_name) = @_;
+    my %coercion_map = @{$self->type_coercion_map};
+    exists $coercion_map{$type_name} ? 1 : 0;
+}
+
+sub add_type_coercions {
+    my ($self, @new_coercion_map) = @_;
+        
+    my $coercion_map = $self->type_coercion_map;    
+    my %has_coercion = @$coercion_map;
+    
+    while (@new_coercion_map) {
+        my ($constraint_name, $action) = splice(@new_coercion_map, 0, 2);        
+        
+        confess "A coercion action already exists for '$constraint_name'"
+            if exists $has_coercion{$constraint_name};
+        
+        push @{$coercion_map} => ($constraint_name, $action);
+    }
+    
+    # and re-compile ...
+    $self->compile_type_coercion;
+}
+
+sub coerce { $_[0]->_compiled_type_coercion->($_[1]) }
+
 
 1;
 
@@ -17,18 +100,39 @@ __END__
 
 =head1 NAME
 
-Moose::Meta::TypeCoercion - The Moose Type Coercion metaobject
-
-=head1 SYNOPSIS
+Moose::Meta::TypeCoercion - The Moose Type Coercion metaclass
 
 =head1 DESCRIPTION
 
+For the most part, the only time you will ever encounter an 
+instance of this class is if you are doing some serious deep 
+introspection. This API should not be considered final, but 
+it is B<highly unlikely> that this will matter to a regular 
+Moose user.
+
+If you wish to use features at this depth, please come to the 
+#moose IRC channel on irc.perl.org and we can talk :)
+
 =head1 METHODS
 
 =over 4
 
 =item B<meta>
 
+=item B<new>
+
+=item B<compile_type_coercion>
+
+=item B<coerce>
+
+=item B<type_coercion_map>
+
+=item B<type_constraint>
+
+=item B<has_coercion_for_type>
+
+=item B<add_type_coercions>
+
 =back
 
 =head1 BUGS
@@ -43,11 +147,11 @@ Stevan Little E<lt>stevan@iinteractive.comE<gt>
 
 =head1 COPYRIGHT AND LICENSE
 
-Copyright 2006 by Infinity Interactive, Inc.
+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. 
 
-=cut
\ No newline at end of file
+=cut