Why don't other programming languages have ranges?

[bearophile]

J. M. Berger:
> 	Plus, how do you prove the proof? I know of at least two examples
> of software that were proven formally and that AFAIK worked
> perfectly to spec and yet failed spectacularly.

You have to think about proofs as another (costly) tool to avoid bugs/bangs, but not as the ultimate and only tool you have to use (I think dsimcha was trying to say that there are more costly-effective tools. This can be true, but you can't be sure that is right in general).

Bye,
bearophile