[Haskell-cafe] Equivalent of if/then/else for IO Bool?
dagit at eecs.oregonstate.edu
Fri Nov 24 04:15:12 EST 2006
On 11/23/06, Conor McBride <ctm at cs.nott.ac.uk> wrote:
> *Grr> ifM (Just True) (Just 3) Nothing
> More care required!
Thank you. Now that you point this out I recall that I've made this
mistake in the past with (&&), I once wrote something like liftM2
(&&). I forget that the liftM* family binds the parameters before
passing them on. Hopefully the lesson will stick this time.
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