Hi,
Sorry for the spam.
I am new to Haskell.
I want to define my own typeclass which can convert from my own types like MyBool, MyInt, and MyString to according Haskell types.
Here is my code:
module Conversion where
import qualified Prelude
class Conversion a where
conversion :: a -> b
data MyBool = MyTrue | MyFalse
instance Conversion MyBool where
conversion MyTrue = Prelude.True
conversion MyFalse =Prelude.False
Here is the error message:
Couldn't match expected type `b' with actual type `Prelude.Bool'
`b' is a rigid type variable bound by
the type signature for conversion :: MyBool -> b
at Conversion.hs:11:5
Does anyone know what's wrong with my code, and how to fix it?
Any hints will be appreciated !!