Erlangs pattern matching is a superior form of this concept. Clojures multimethods also implement a similar style to erlangs pattern matching dispatch. Both of

Erlangs pattern matching is a superior form of this concept. Clojures multimethods also implement a similar style to erlangs pattern matching dispatch. Both of those avoid some of the objections described in other comments here. The code is still in core and is easier to read than a dispatch table.