Hello, Maybe, using fmap would be enough? data Proxy = Proxy String f :: Maybe Proxy -> Maybe String f = fmap (\(Proxy a) -> a) 2017-08-25 15:00 GMT+03:00 :

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Today's Topics:

1. Maybe a -> Maybe b (PICCA Frederic-Emmanuel)

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Message: 1 Date: Fri, 25 Aug 2017 08:05:34 +0000 From: PICCA Frederic-Emmanuel To: "beginners@haskell.org" Subject: [Haskell-beginners] Maybe a -> Maybe b Message-ID:

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Hello, I have this

data Proxy = Proxy String

And I want to write a function

f :: Maybe Proxy -> Maybe String f ma = case ma of (Just (Proxy a)) -> Just a Nothing -> Nothing

I was wondering if there is no simpler way to do this ?

thanks

Frederic

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