http://qs1969.pair.com?node_id=508769


in reply to Re: How to use Inheritance with Inside-Out Classes and Hash Based Classes
in thread How to use Inheritance with Inside-Out Classes and Hash Based Classes

This is also called delegation. Its generally preferred to ISA anyway since it doesn't specify that a particular object *is* another kind of thing, it has-a the other object, uses it, and forwards appropriate things through.