On Tue, May 31, 2011 at 3:49 PM, Scott Lawrence
I was under the impression that operations performed in monads (in this case, the IO monad) were lazy. (Certainly, every time I make the opposite assumption, my code fails :P .) Which doesn't explain why the following code fails to terminate:
iRecurse :: (Num a) => IO a iRecurse = do recurse <- iRecurse return 1
main = (putStrLn . show) =<< iRecurse
Any pointers to a good explanation of when the IO monad is lazy?
import System.IO.Unsafe iRecurse :: (Num a) => IO a iRecurse = do recurse <- unsafeInterleaveIO iRecurse return 1 More interesting variations of this leave you with questions of whether or not the missles were launched, or, worse yet, was data actually read from the file handle? Anthony