Re: 'while' loop on mutable arrays causes stack overflow

Hello Gunnar, Thursday, April 20, 2006, 4:29:29 PM, you wrote:

a friend and I were recently experimenting with mutable arrays. We tried to implement a simple dot product on STUArrays using a 'while' loop. Unfortunately, every implementation we produced caused a stack overflow.

it seems that you just construct huge unevaluated thunk. making things stricter is a whole art, in this case try the following:

...

writeSTRef b (ev

writeSTRef b $! (ev

...

for :: Int -> IO () -> IO () for 0 c = return () for n c = c >> for (n-1) c

i recommend you to use your `for` instead of your `while` - it's a much faster and straightforward -- Best regards, Bulat mailto:Bulat.Ziganshin@gmail.com