Or put another way: Compilers are good att figuring out what a function _can_ do. But humans need to specify what it _should_ do. Types aren’t always the right

Or put another way: Compilers are good att figuring out what a function _can_ do. But humans need to specify what it _should_ do. Types aren’t always the right tool for that though. It would be interesting to see what could be done by integrating testing and typing, letting one inform the other.