class T::Props::Decorator

def prop_get(instance, prop, rules=prop_rules(prop))
  val = instance.instance_variable_get(rules[:accessor_key])
  if !val.nil?
    val
  else
    if (d = rules[:ifunset])
      T::Props::Utils.deep_clone_object(d)
    else
      nil
    end
  end
end