hi,

data StringOrInt = TisanInt Int | TisAString String

instance Eq (StringOrInt) where 

(==) (TisanInt v) (TisanInt v') = v == v'

(==) (TisAString s) (TisAString s') = s == s'

prelude>

Instance_testen.hs:4:37: error:

    Ambiguous occurrence ‘==’

    It could refer to either ‘Prelude.==’,

                             imported from ‘Prelude’ at Instance_testen.hs:1:1

                             (and originally defined in ‘GHC.Classes’)

                          or ‘Main.==’, defined at Instance_testen.hs:4:1

  |

4 | (==) (TisanInt v) (TisanInt v') = v == v'   |                                     ^^

Instance_testen.hs:5:41: error:

    Ambiguous occurrence ‘==’

    It could refer to either ‘Prelude.==’,

                             imported from ‘Prelude’ at Instance_testen.hs:1:1

                             (and originally defined in ‘GHC.Classes’)

                          or ‘Main.==’, defined at Instance_testen.hs:4:1

  |

5 | (==) (TisAString s) (TisAString s') = s == s' 

  |                                         ^^

[1 of 1] Compiling Main             ( Instance_testen.hs, interpreted )

Failed, no modules loaded.

what gives?

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