Racket, of course!

Very sophisticated contract system and exceptions and reified continuations.

It's dynamic, JITed language, and it's a Lisp, but I recommend studying it just for the sake of learning various techniques Racket uses. They are frequently very interesting from the language design perspective and their usage is easier to understand than in Haskell :)

It sounded a lot like Eiffel[1] to me, except they also have traditional Exceptions when you need them.

[1] http://en.wikipedia.org/wiki/Eiffel_(programming_language)#E...