{-# htermination (absRatio :: Ratio MyInt -> Ratio MyInt) #-} import qualified Prelude data MyBool = MyTrue | MyFalse data List a = Cons a (List a) | Nil data MyInt = Pos Nat | Neg Nat ; data Nat = Succ Nat | Zero ; data Ordering = LT | EQ | GT ; data Ratio a = CnPc a a; primNegInt :: MyInt -> MyInt; primNegInt (Pos x) = Neg x; primNegInt (Neg x) = Pos x; negateMyInt :: MyInt -> MyInt negateMyInt = primNegInt; absReal0 x MyTrue = negateMyInt x; otherwise :: MyBool; otherwise = MyTrue; absReal1 x MyTrue = x; absReal1 x MyFalse = absReal0 x otherwise; fromIntMyInt :: MyInt -> MyInt fromIntMyInt x = x; primCmpNat :: Nat -> Nat -> Ordering; primCmpNat Zero Zero = EQ; primCmpNat Zero (Succ y) = LT; primCmpNat (Succ x) Zero = GT; primCmpNat (Succ x) (Succ y) = primCmpNat x y; primCmpInt :: MyInt -> MyInt -> Ordering; primCmpInt (Pos Zero) (Pos Zero) = EQ; primCmpInt (Pos Zero) (Neg Zero) = EQ; primCmpInt (Neg Zero) (Pos Zero) = EQ; primCmpInt (Neg Zero) (Neg Zero) = EQ; primCmpInt (Pos x) (Pos y) = primCmpNat x y; primCmpInt (Pos x) (Neg y) = GT; primCmpInt (Neg x) (Pos y) = LT; primCmpInt (Neg x) (Neg y) = primCmpNat y x; compareMyInt :: MyInt -> MyInt -> Ordering compareMyInt = primCmpInt; 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; not :: MyBool -> MyBool; not MyTrue = MyFalse; not MyFalse = MyTrue; fsEsOrdering :: Ordering -> Ordering -> MyBool fsEsOrdering x y = not (esEsOrdering x y); gtEsMyInt :: MyInt -> MyInt -> MyBool gtEsMyInt x y = fsEsOrdering (compareMyInt x y) LT; absReal2 x = absReal1 x (gtEsMyInt x (fromIntMyInt (Pos Zero))); absReal x = absReal2 x; absMyInt :: MyInt -> MyInt absMyInt = absReal; absRatio :: Ratio MyInt -> Ratio MyInt absRatio (CnPc x y) = CnPc (absMyInt x) y;