Shoot, it's been too long for me to sort out the various features now, but you can read about the cooler parts of arc here: http://old.ycombinator.com/arc/tut.t

Shoot, it's been too long for me to sort out the various features now, but you can read about the cooler parts of arc here: http://old.ycombinator.com/arc/tut.txt http://old.ycombinator.com/arc/tut.txt which won't look very exciting to any Clojure programmer nowadays. Probably its most useful innovation, even if it sounds mundane now (and I'm not 100% sure it was first on this- feel free to correct me) is that it was the first Lisp to realize that sequences and key-value associations are both equally important and should both have first-class status in the core language (with proper literal and shortcut accessor support) ... so like clojure, arc is more of a MLISP (Map and LISt Processor) However, the posted link doesn't have examples of the crazy syntactic sugar stuff pg did that I think was added in a later revision.