4 Apr
2007
4 Apr
'07
6:58 p.m.
Hello Matthew, Thursday, April 5, 2007, 2:00:03 AM, you wrote:
main = do hSetBuffering stdin NoBuffering hGetContents stdin >>= mapM addTimeCode >>= mapM_ handleChar
It seems to wait till the end of the infinite list. Why?
The sequencing imposed by the IO monad means that the first mapM must complete before the second can start. To see this, you can try the following:
or, alternatively, replace first mapM_ with unsafeInterleavedMapM: unsafeInterleavedMapM f (x:xs) = do a <- f x as <- unsafeInterleaveIO (unsafeInterleavedMapM f xs) return (a:as) (not tested) -- Best regards, Bulat mailto:Bulat.Ziganshin@gmail.com