{-# LANGUAGE DataKinds, PolyKinds, TypeOperators, TypeFamilies , TypeApplications, TypeInType #-} module DumpParsedAst where import Data.Kind data Peano = Zero | Succ Peano type family Length (as :: [k]) :: Peano where Length (a : as) = Succ (Length as) Length '[] = Zero -- vis kind app data T f (a :: k) = MkT (f a) type family F1 (a :: k) (f :: k -> Type) :: Type where F1 @Peano a f = T @Peano f a main = putStrLn "hello"