The saving grace here is that it destroys classes. I have often seen deep clone and deep equals as a sort of back-door API that then breaks when the implementat

The saving grace here is that it destroys classes. I have often seen deep clone and deep equals as a sort of back-door API that then breaks when the implementation of the class does. The fact that this ignores prototypes makes it clear that you should only be using this for data, not "OO Objects".