No, I think Artyom meant "assuming IO is lazy".
He intended to show that, indeed, it is not, or else side-effects would
never be performed
2011/5/31 Scott Lawrence
On 05/31/2011 04:20 PM, Artyom Kazak wrote:
Suppose iRecurse looks like this: iRecurse = do x <- launchMissiles r <- iRecurse return 1
As x is never needed, launchMissiles will never execute. It obviously is not what is needed.
Prelude> let launchMissiles = putStrLn "UH OH" >> return 1 Prelude> let iRecurse = launchMissiles >> return 1 Prelude> iRecurse UH OH 1 Prelude>
Looks like launchMissiles /does/ execute, even though x is (obviously) never needed.
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