find attributes type_constraints

Hello,
I am trying to make an object report the type constraints for its attributes.
given a class, which defines attributes like :


has 'test_attribute' => (isa     => 'ArrayRef',
                               is      => 'ro',
                               default => sub{[]},
                           );

has 'instance_view'    => (isa  => 'TkObjectsView',
                            is   => 'rw',
                        );

where 'ArrayRef' is the builtin type_constraint and 'TkObjectsView' is a simple
classname.

Is there a way to retrieve the types of these attributes from an instance?
If I do something like:

for my $attr(@attributes){
     my $tc = $attr->type_constraint;
     print Dumper $tc;
     print "\n\n";
}

I get the following output:

$VAR1 = bless( {
                  'compiled_type_constraint' => 'CODE(0x1bceb14)',
                  'parent' => 'Ref',
                  'name' => 'ArrayRef',
                  'coercion' => undef,
                  'hand_optimized_type_constraint' => 'CODE(0x1bf6660)',
                  'constraint' => 'CODE(0x1bf65f4)',
                  'message' => undef
                }, 'Moose::Meta::TypeConstraint' );


$VAR1 = bless( {
                  'compiled_type_constraint' => 'CODE(0x1c71e54)',
                  'parent' => 'Object',
                  'name' => '__ANON__',
                  'coercion' => undef,
                  'hand_optimized_type_constraint' => undef,
                  'constraint' => 'CODE(0x1c71a10)',
                  'message' => undef
                }, 'Moose::Meta::TypeConstraint' );

'ArrayRef' is in the name attribute of the TypeConstraint, but I don't see a way 
to get the classname 'TkObjectsView' back out of the second type_constraint 
object. (Except, maybe, by using B::Deparse ;) )
Am I missing something?
Will I have to explicitly create a 'Moose::Meta::TypeConstraint' for every class
I want to use in an attribute to make this work?

Thanks, Christoph Lamprecht