I just want to say that even though, I haven't really had time to digest what Christophe has written, I think it looks great! I really like that you've been able to extend the "normal" CL sequence facilities so that you can use "regular" Lisp code with all kinds of new sequence types. That feels like a big win over having to rewrite everything with generic functions. -- Gary Warren King, metabang.com Cell: (413) 885 9127 Fax: (206) 338-4052 gwkkwg on Skype * garethsan on AIM