$meta_instance->rebless_instance_structure($instance, $new_metaclass);
# check and upgrade all attributes
- my %params = map { $_->name => $_->get_value($instance) }
+ my %params = map { $_->name => $meta_instance->get_slot_value($instance, $_->name) }
grep { $meta_instance->is_slot_initialized($instance, $_->name) }
$new_metaclass->compute_all_applicable_attributes;