[Haskell-beginners] instance

Alexander Chen alexander at chenjia.nl
Wed Apr 22 18:10:23 UTC 2020


data TisanInteger = Tisan Integer

instance Eq (Tisan Integer) where (Tisan v) == (Tisan v') = v == v'

Instance_testen.hs:7:14: error:
    Not in scope: type constructor or class ‘Tisan’
    A data constructor of that name is in scope; did you mean DataKinds?
7 | instance Eq (Tisan Integer) where (Tisan v) == (Tisan v') = v == v'   |              ^^^^^
[1 of 1] Compiling Main             ( Instance_testen.hs, interpreted )
Failed, no modules loaded.

what am i doing wrong?

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