Yes, lots of OO research happened and happens in smalltalk. Which is why it has such a flexible object system, and which is why it is so well suited for OO rese

Yes, lots of OO research happened and happens in smalltalk. Which is why it has such a flexible object system, and which is why it is so well suited for OO research :-) The Common Lisp Object System (CLOS) also uses meta classes; there's a book about it: "The Art of the Meta Object Protocol", http://www.amazon.com/Art-Metabobject-Protocol-Metaobject/dp/0262610744 http://www.amazon.com/Art-Metabobject-Protocol-Metaobject/dp... Sadly it seems to be the only approachable resource on meta object systems, apart from a few research papers. If anybody has more literature reference, I'd be happy to learn about them.