elem_5.hs

contents

{-# htermination (elemFloat :: Float  ->  (List Float)  ->  MyBool) #-} 
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 ;

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 :: (a  ->  b)  ->  (c  ->  a)  ->  c  ->  b;
pt f g x = f (g x);

any :: (a  ->  MyBool)  ->  (List a)  ->  MyBool;
any p = pt or (map p);

primEqNat :: Nat  ->  Nat  ->  MyBool;
primEqNat Zero Zero = MyTrue;
primEqNat Zero (Succ y) = MyFalse;
primEqNat (Succ x) Zero = MyFalse;
primEqNat (Succ x) (Succ y) = primEqNat x y;

primEqInt :: MyInt  ->  MyInt  ->  MyBool;
primEqInt (Pos (Succ x)) (Pos (Succ y)) = primEqNat x y;
primEqInt (Neg (Succ x)) (Neg (Succ y)) = primEqNat x y;
primEqInt (Pos Zero) (Neg Zero) = MyTrue;
primEqInt (Neg Zero) (Pos Zero) = MyTrue;
primEqInt (Neg Zero) (Neg Zero) = MyTrue;
primEqInt (Pos Zero) (Pos Zero) = MyTrue;
primEqInt vv vw = MyFalse;

esEsMyInt :: MyInt  ->  MyInt  ->  MyBool
esEsMyInt = primEqInt;

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));

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;

primEqFloat :: Float  ->  Float  ->  MyBool;
primEqFloat (Float x1 x2) (Float y1 y2) = esEsMyInt (srMyInt x1 y1) (srMyInt x2 y2);

esEsFloat :: Float  ->  Float  ->  MyBool
esEsFloat = primEqFloat;

elemFloat :: Float  ->  (List Float)  ->  MyBool
elemFloat = pt any esEsFloat;

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