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Today's Topics:
1. better exception handling (Miro Karpis)
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Message: 1
Date: Wed, 23 Oct 2013 23:11:32 +0200
From: Miro Karpis <[email protected]>
To: The Haskell-Beginners Mailing List - Discussion of primarily
beginner-level topics related to Haskell <[email protected]>
Subject: [Haskell-beginners] better exception handling
Message-ID:
<cajnnbxegthc8u8hvg5ocv7bc6k-xijdgnr6fe3ivf6_ei2j...@mail.gmail.com>
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Please, can you help me with following?... I have a working code but am not
very happy with the error handling in "updateStocks" function. It does what
it should, but I would like to implement some kind of guards. Problem is
that it always ends it some error + am not sure if I can use guards in
inside defined variable. Pls. what would you suggest?
httpExceptionHandler :: HttpException -> IO L.ByteString
httpExceptionHandler e = (putStrLn "Error: simpleHttp returned exception ")
>> (return L.empty)
getStocks :: String -> IO L.ByteString
getStocks url = (simpleHttp url) `X.catch` httpExceptionHandler
updateStocks :: IO String
updateStocks = do
yqlResult <- getStocks testQuery
case yqlResult of x | x == L.empty -> return "return exception"
| otherwise -> return "here I will call
another function"
thanks,
m.
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