[Haskell] Monadic Loops

[Arjan van IJzendoorn]

Hello,

Vivian uses this while function:

while test body = do
                  (cond,res) <- body
                  if (test cond) then do rs <- while test body
                                      return (res:rs)
                  else return [res]

> However, when I run the program, the interpreter falls over after a few
thousand iterations, running out of space.

Maybe making it tail-recursive helps. Let me think...... untested code
ahead:

while test body =
    do
        res <- funnyWhile test body []
        return (reverse res)

funnyWhile test body revResult =
    do
        (cond, res) <- body
        if test cond then
            while test body (res:revResult)
       else
            return revResult

Greetings, Arjan