{-# htermination (elemOrdering :: Ordering -> (List Ordering) -> MyBool) #-} import qualified Prelude data MyBool = MyTrue | MyFalse data List a = Cons a (List a) | Nil data Ordering = LT | EQ | GT ; map :: (b -> a) -> (List b) -> (List a); map f Nil = Nil; map f (Cons x xs) = Cons (f x) (map f xs); foldr :: (b -> a -> a) -> a -> (List b) -> a; foldr f z Nil = z; foldr f z (Cons x xs) = f x (foldr f z xs); pePe :: MyBool -> MyBool -> MyBool; pePe MyFalse x = x; pePe MyTrue x = MyTrue; or :: (List MyBool) -> MyBool; or = foldr pePe MyFalse; pt :: (c -> a) -> (b -> c) -> b -> a; pt f g x = f (g x); any :: (a -> MyBool) -> (List a) -> MyBool; any p = pt or (map p); esEsOrdering :: Ordering -> Ordering -> MyBool esEsOrdering LT LT = MyTrue; esEsOrdering LT EQ = MyFalse; esEsOrdering LT GT = MyFalse; esEsOrdering EQ LT = MyFalse; esEsOrdering EQ EQ = MyTrue; esEsOrdering EQ GT = MyFalse; esEsOrdering GT LT = MyFalse; esEsOrdering GT EQ = MyFalse; esEsOrdering GT GT = MyTrue; elemOrdering :: Ordering -> (List Ordering) -> MyBool elemOrdering = pt any esEsOrdering;