Imperative and (pure) functional are not opposites! They are actually orthogonal.
The opposite of imperative is declarative, and the opposite of (pure) functional is non (pure) functional.
Schema and (to my limited knowldge) the ML family are in fact non (pure) functional. However, they share more functional-aspects with pure functional languages than most other popular languages do.
> Even Haskell has unsafePerformIO, which it might sadly need.
Sure, it's almost never a black and white thing. But I think for the sake of the argument we can call Haskell a pure functional language, even if it is indeed possible to write non pure functional code in it. There are actual pure functional languages (like Idris) but I think for practical use in the discussion it's fine to call Haskell pure functional. Scheme and ML languages are very different from Haskell though, so I think they deserve to be called differently. They are however also different from, say, C. So to improve our communication I think it is worth to not put those 3 things into 2 boxes. We need 3 boxes here.
Disclaimer: I want to emphasize that none of any of that says that a language is inherentially better or worse! This is just terminology-talk.
