Re: [Haskell-beginners] maybe in IO

Of course there is "return ()" missing. check x assoc = case lookup x of Just found -> putStrLn ("found " ++ found) _ -> return () On Thu, Aug 1, 2013 at 5:34 PM, Krzysztof Skrzętnicki wrote:

I'd rather use pattern matching in this case:

check x assoc = case lookup x of Just found -> putStrLn ("found " ++ found) _ ->

Not really shorter but I think it's cleaner this way.

On Thu, Aug 1, 2013 at 5:00 PM, vold wrote:

...

I've defined a function similar to

check x assoc = let found = lookup x assoc in when (isJust found) $ putStrLn $ "found " ++ fromJust found

which I've used several times from within the IO monad. Is there a more compact way of doing this?

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