[Haskell-beginners] using the current time
Edward Z. Yang
ezyang at MIT.EDU
Tue Dec 8 18:33:30 EST 2009
Excerpts from Torsten Otto's message of Tue Dec 08 18:18:54 -0500 2009:
> > time = formatiereZeit (NOW WHAT?)
> Would the current time step out of the IO monad, please?
Unfortunately, there is no way to "step out" of the IO monad:
once in the IO monad, always in the IO monad.
However, if you let time be of type IO String instead of String,
you can do:
time = (liftM formatiereZeit) getClockTime
Where liftM :: (a -> b) -> m a -> m b, i.e. it converts
your function ClockTime -> String into IO ClockTime -> IO String.
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