Re: [Haskell-cafe] csv one-liner

On Wed, 2008-10-01 at 10:15 +0200, Ketil Malde wrote:

Derek Elkins writes:

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parseCSVFromFile "in.csv" >>= return . either (const "error!")

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Whenever you see this >>= return . f pattern think liftM or fmap or <$>.

...and "return . f >>= action" is just "action . f", no?

Well actually that's \x -> action (return (f x)) x via the (r ->) instance of Monad. I think what you wanted was \x -> return (f x) >>= action which is \x -> action (f x) action . f via the monad laws.