Re: [Haskell-cafe] Re: Haskell code for this example of flow control

2 Feb 2006


      On 2/2/06, Maurício  wrote:
...
I understand those examples, but I really would like to know how to
do that with monads. I would like to ask the same question, but now with
this code:
double a = 1000;
double b = 0;
while (a != b) {
     a /= 2;
     cout << a; // Prints a
     cin << b; // User gives a number, stored in b
};
An idiomatic approach:
example :: Double -> Double -> IO ()
example a b
    | a == b    = return ()
    | otherwise = do
        let a' = a / 2
        print a'
        b' <- readLn
        example a' b'

main = example 1000 0

Re: [Haskell-cafe] Re: Haskell code for this example of flow control

Kurt Hutchinson