Wow! That's a much more detailed response than I'd expected. Thank you! I wish I could upvote you twice! :) I've used Common Lisp and even SBCL quite a bit

Wow! That's a much more detailed response than I'd expected. Thank you! I wish I could upvote you twice! :) I've used Common Lisp and even SBCL quite a bit, and had no idea SBCL could do some of this stuff. That last example is particularly impressive, given how hairy control-flow analysis can get when higher-order functions are involved.