{-# LANGUAGE DataKinds #-}
{-# LANGUAGE TypeFamilies #-}
{-# LANGUAGE TypeFamilyDependencies #-}
{-# LANGUAGE UndecidableInstances #-}
module M where
import Data.Kind (Type)

type MapList :: (Type -> Type) -> [Type] -> [Type]
type family MapList f xs = r | r -> xs where
  MapList f '[] = '[]
  MapList f (x ': xs) = f x ': MapList f xs