[Haskell] Set of an Unordered Data Type with a given ordering

Posted by Ingdas on Stack Overflow See other posts from Stack Overflow or by Ingdas
Published on 2010-03-25T08:29:45Z Indexed on 2010/03/25 8:33 UTC
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haskell

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ordering

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set

I'm trying to put this data type in a Haskell Set, but I don't want to give it a general instance of Ord. So I want to give the set an ordering on y-coördinate but without instance Ord Vector. Is this possible?

    data Vector = V 
    { x :: Double
    , y :: Double
    } deriving (Eq)

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