Common Lisp has had those kind of optimizations for ages. You tell it what your variables hold, and how much effort it should spend compiling for speed, and it figures out the rest. The only catch is that it still does garbage collection.
in reply to Re: Nested data structures... nasty?
in thread Nested data structures... nasty?
For a real example of Common Lisp used in a high-performance situation, read this description of how Orbitz works.