-- @shouldFailWith NoInstanceFound module Main where data Proxy a = Proxy class C a b where c :: Proxy a -> Proxy b -> Boolean instance C String (Array a) where c _ _ = true else instance c2 :: C String a where c _ _ = false fn :: forall a b. Proxy a -> Proxy b -> Int fn _ _ = 42 where x = c (Proxy :: Proxy a) (Proxy :: Proxy b)