The most famous piece of Lisp-related vaporware is vapor no longer: Arc has been released. After paging through the tutorial, I’m a bit underwhelmed. It looks like just a bunch of syntactic sugar implemented on top of Scheme. Clojure is more interesting and more innovative. Clojure and Arc have some things in common: data structures are functions on their keys, strings are sequences, and lambda is “fn”. But Arc seems to be more in the traditional, semi-imperative model whereas Clojure borrows heavily from functional programming. Arc even has for-loops, for goodness sakes. Obviously, I have no idea what else Paul Graham may have up his sleeve, so maybe there’s much more exciting stuff to come. But for now Arc looks to me like a modest improvement on Common Lisp / Scheme rather than a major new language.