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Comment by lpw25 | Hacker News Reader

It's not a strawman. Just look at the code for reverse-complement in Haskell. It is full of strictness annotations (unidiomatic) and uses inlinePerformIO (unsafe). It also uses a few inlining pragmas (unidiomatic).

The fact that this code is fast tells you nothing about whether idiomatic Haskell is fast. wrong evidence < no evidence.

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Strictness annotations are idiomatic in Haskell.

Yes, it is a strawman. Strictness annotations are not unidiomatic any more than using laziness is in ocaml. The ocaml code is effectively using unsafePerformIO all over, ocaml doesn't offer the safety you are complaining that the haskell example gives up. And both of your invalid complaints are completely irrelevant to the question at hand.

The question was about difficulty, not a subjective idea of what idiomatic code looks like. Are you seriously claiming that the average haskell example there is more difficult to write than the average ocaml example? If so, just say that. Trying to redirect the discussion back to your subjective preferences is not productive.

Note that using `unsafePerformIO` is more unsafe than that, because the compiler assumes that functions are pure and will make transformations which alter the semantics in the presence of side effects. The OCaml compiler does not do these optimisations because it has to assume everything is impure.

And `inlinePerformIO` is much more unsafe, because it requires that you do no memory allocation inside it. This property is specific to the Haskell implementation, and is certainly not easy to guarantee.

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