Haskell Learnings

TypeclassStuff.hs

{-# LANGUAGE FlexibleInstances #-}
{-# LANGUAGE KindSignatures #-}

class Zomg a where
  zomg :: a -> String

data Errr a = Errr a

instance Zomg (Errr a) where
  zomg a = "ROckin"

class Zomg2 (f :: * -> *) where
  zomg2 :: f a -> String

instance Zomg2 Errr where
  zomg2 a = "ROckin"

instance Functor Errr where
  fmap f (Errr a) = Errr $ f a


instance Num a => Zomg (Blah a)
  zomg = undefined

instance IsString a => Zomg (Blah a)
  zomg = undefined