Re: [Haskell-beginners] \x -> x < 0.5 && x > -0.5

19 Oct 2009


      On Mon, Oct 19, 2009 at 9:49 AM, Michael Mossey  wrote:
...
Is there a nifty way to write
filter (\x -> x < 0.5 && x > -0.5) xs
without explicitly using x?
Maybe arrows? I have a vague understanding that arrows can "send" an
argument to more than one computation.
Using &&& from Control.Arrow you can write something like

    file (uncurry (&&) . ((< 0.5) &&& (> -0.5))) xs

/M

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Magnus Therning                        (OpenPGP: 0xAB4DFBA4)
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