Tomasz Zielonka writes: | On Sat, Apr 19, 2003 at 12:29:13PM +1200, Tom Pledger wrote: | > You should get the same result with | > | > modifyIORef r $! <E> | | But this will only force evaluation of the function passed to | modifyIORef, won't it? You're right. My mistake, sorry. <E> is already in Weak Head Normal Form (because it's a function), so the ($!) has no effect.