Fast dispatch mechanisms for stock hardware

Common Lisp ‘[Steele] can be Characterized as an “almost object oriented” language, in that it supports a fixed set of generic functions (e.g., ELT) and a type structure which is open-ended enough to allow for extension of those functions. Alas, this extension cannot be done by application programmers, but is reserved for implementors. It is a common need for language designers and other researchers to extend generic operations; they are usually reduced to unsatisfactory package-system kludges. For example, both [Hillis] and [Sabot] define new sequence types while adapting Common Lisp to massively parallel hardware.