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lalaithion on Oct 17, 2019 | parent | context | favorite | on: Haskell in Production

    • Couldn't match expected type ‘([Integer] -> [Integer]) -> [b]’
                  with actual type ‘[Integer]’
    • Possible cause: ‘map’ is applied to too many arguments
      In the second argument of ‘(&)’, namely ‘map (* 2) [1, 2, 3]’
      In the second argument of ‘($)’, namely
        ‘map (+ 2) & map (* 2) [1, 2, 3]’
      In the expression: map (+ 2) $ map (+ 2) & map (* 2) [1, 2, 3]

dmitriid on Oct 18, 2019 [–]

In my opinion this doesn’t help much.

deterministic on Oct 18, 2019 | [–]

Of course not. You have to learn how the type system works to get it.

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