Imperative Haskell
As far as I&#x27;m concerned, purity is more fundamental than impurity, because we can always emulate impurity using a pure language (as is shown in this article), but it&#x27;s not possible to emulate purity using an impure language.<p>This only leaves us with the challenge of performance. While we can always describe e.g. x86 assembly in terms of a pure intermediate representation language (e.g. GHC Core), transforming this description back into equally performant x86 doesn&#x27;t seem easy.<p>Also, anyone care to produce some benchmarks comparing the imperative Python&#x2F;Haskell quicksort implementations? They look so similar, it&#x27;d be quite interesting to see how well GHC can optimize this sort of stuff.