[gnosis]

That's good to know, and gives me extra incentive to learn Haskell some day.

On the Scheme side of things, I've heard that the newish (4.8.0 and up) versions of Chicken can perform flow analysis to catch some type errors at compile time, and optimize based on types.

There's also Typed Racket, and Chicken has a contracts egg that allows procedures to have pre- and post- conditions.

For some years now, I've heard predictions that in the future languages will allow their users to "dial up" or "dial down" safety features on demand. I guess the above features of Scheme and Haskell are some early steps along that path. We live in interesting times.