{-# htermination (takeWhile :: (a  ->  MyBool)  ->  (List a)  ->  (List a)) #-} 
import qualified Prelude 
data MyBool = MyTrue | MyFalse 
data List a = Cons a (List a) | Nil 
otherwise :: MyBool;
otherwise = MyTrue;

takeWhile0 p x xs MyTrue = Nil;

takeWhile1 p x xs MyTrue = Cons x (takeWhile p xs);
takeWhile1 p x xs MyFalse = takeWhile0 p x xs otherwise;

takeWhile2 p (Cons x xs) = takeWhile1 p x xs (p x);

takeWhile3 p Nil = Nil;
takeWhile3 vx vy = takeWhile2 vx vy;

takeWhile :: (a  ->  MyBool)  ->  (List a)  ->  (List a);
takeWhile p Nil = takeWhile3 p Nil;
takeWhile p (Cons x xs) = takeWhile2 p (Cons x xs);