{-# htermination (enumFromFloat :: Float -> (List Float)) #-} import qualified Prelude data MyBool = MyTrue | MyFalse data List a = Cons a (List a) | Nil data Float = Float MyInt MyInt ; data MyInt = Pos Nat | Neg Nat ; data Nat = Succ Nat | Zero ; data WHNF a = WHNF a ; enforceWHNF :: WHNF b -> a -> a; enforceWHNF (WHNF x) y = y; seq :: a -> b -> b; seq x y = enforceWHNF (WHNF x) y; dsEm :: (b -> a) -> b -> a; dsEm f x = seq x (f x); primIntToFloat :: MyInt -> Float; primIntToFloat x = Float x (Pos (Succ Zero)); fromIntFloat :: MyInt -> Float fromIntFloat = primIntToFloat; primMinusNat :: Nat -> Nat -> MyInt; primMinusNat Zero Zero = Pos Zero; primMinusNat Zero (Succ y) = Neg (Succ y); primMinusNat (Succ x) Zero = Pos (Succ x); primMinusNat (Succ x) (Succ y) = primMinusNat x y; primPlusNat :: Nat -> Nat -> Nat; primPlusNat Zero Zero = Zero; primPlusNat Zero (Succ y) = Succ y; primPlusNat (Succ x) Zero = Succ x; primPlusNat (Succ x) (Succ y) = Succ (Succ (primPlusNat x y)); primPlusInt :: MyInt -> MyInt -> MyInt; primPlusInt (Pos x) (Neg y) = primMinusNat x y; primPlusInt (Neg x) (Pos y) = primMinusNat y x; primPlusInt (Neg x) (Neg y) = Neg (primPlusNat x y); primPlusInt (Pos x) (Pos y) = Pos (primPlusNat x y); psMyInt :: MyInt -> MyInt -> MyInt psMyInt = primPlusInt; primMulNat :: Nat -> Nat -> Nat; primMulNat Zero Zero = Zero; primMulNat Zero (Succ y) = Zero; primMulNat (Succ x) Zero = Zero; primMulNat (Succ x) (Succ y) = primPlusNat (primMulNat x (Succ y)) (Succ y); primMulInt :: MyInt -> MyInt -> MyInt; primMulInt (Pos x) (Pos y) = Pos (primMulNat x y); primMulInt (Pos x) (Neg y) = Neg (primMulNat x y); primMulInt (Neg x) (Pos y) = Neg (primMulNat x y); primMulInt (Neg x) (Neg y) = Pos (primMulNat x y); srMyInt :: MyInt -> MyInt -> MyInt srMyInt = primMulInt; primPlusFloat :: Float -> Float -> Float; primPlusFloat (Float x1 x2) (Float y1 y2) = Float (psMyInt x1 y1) (srMyInt x2 y2); psFloat :: Float -> Float -> Float psFloat = primPlusFloat; numericEnumFrom n = Cons n (dsEm numericEnumFrom (psFloat n (fromIntFloat (Pos (Succ Zero))))); enumFromFloat :: Float -> (List Float) enumFromFloat = numericEnumFrom;