Reminds me a lot of how the common lisp object system evolved (or even C++). You start with an extension to the language, then it gets formalised, then it beco

Reminds me a lot of how the common lisp object system evolved (or even C++). You start with an extension to the language, then it gets formalised, then it becomes something new(ish). Bit like evolution continuing to come up with the same answers in different evolutionary trees. Bit of a shame that the javascript guys didn't look at CLOS it might have been quite easy to port across. They do seem to share some implementation details (like the way which function is the right one to run).