Merge branch 'useful_optional'

[gitmo/MooseX-Types-Structured.git] / lib / MooseX / Meta / TypeCoercion / Structured / Optional.pm

diff --git a/lib/MooseX/Meta/TypeCoercion/Structured/Optional.pm b/lib/MooseX/Meta/TypeCoercion/Structured/Optional.pm
new file mode 100644 (file)
index 0000000..340cdc6
--- /dev/null
+++ b/lib/MooseX/Meta/TypeCoercion/Structured/Optional.pm
@@ -0,0 +1,25 @@
+package MooseX::Meta::TypeCoercion::Structured::Optional;
+
+use Moose;
+extends 'Moose::Meta::TypeCoercion';
+
+sub compile_type_coercion {
+    my ($self) = @_;
+    my $constraint = $self->type_constraint->type_parameter;
+
+    $self->_compiled_type_coercion(sub {
+        my ($value) = @_;
+        return unless $constraint->has_coercion;
+        return $constraint->coerce($value);
+    });
+}
+
+sub has_coercion_for_type { 0 }
+
+sub add_type_coercions {
+    Moose->throw_error("Cannot add additional type coercions to Optional types");
+}
+
+__PACKAGE__->meta->make_immutable(inline_constructor => 0);
+
+1;