Donald Bruce Stewart
dons at cse.unsw.edu.au
Tue Feb 20 03:06:58 EST 2007
> I am writing a recursive function which does some IO
> operation. I encounter situation in which my function has to
> end recursion by doing "nothing" and otherwise keep calling
> same function with some different parameters. I did not find
> anything equivalent to "pass" or "return" statement in
> Haskell. Presently I have got a workaround. I am doing it by
> putting a dummy print as described below.
> can anybody help me in this?
> f some_params =
> if some_condition
> then do putStr "Hacky way to do nothing!"
> else do perform_some_IO
> f some_other_params
Two usual ways:
f xs | condition = return ()
| otherwise = do io
f xs = when (not.condition) $ do
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