Re: [Haskell-cafe] Re: Comments on reading two ints off Bytestring

Just curious -- how can this be done in Arrows instead of Manad/T? Or can it? On Dec 26, 2007 6:42 AM, Benja Fallenstein wrote:

On Dec 23, 2007 1:44 PM, Isaac Dupree wrote:

...

parseHeader3 :: BS.ByteString -> Maybe (Int, Int) parseHeader3 bs = do (x, rest) <- BS.readInt $ BS.dropWhile (not . isDigit) bs (y, _) <- BS.readInt $ BS.dropWhile (not . isDigit) rest return (x, y)

But that version still itches! :-)

This is what it sounds like to me:

parseHeader :: BS.ByteString -> Maybe (Int,Int) parseHeader = evalStateT $ liftM2 (,) parseInt parseInt where parseInt = StateT $ BS.readInt . BS.dropWhile (not . isDigit)

- Benja

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