Not to be picky, but where did you hear that (==) established an equivalence relation? Not I expect from the Haskell98 Report! The only law I can find there is that x /= y iff not (x == y) So, the definition x == y = False x /= y = True would be perfectly legitimate, making x /= x = True, which kind of ruins the equivalence relation thing, no? Dan Wolfgang Jeltsch wrote:
Am Mittwoch, 12. März 2008 00:53 schrieb askyle:
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So if floating point (==) doesn't correspond with numeric equality, it's not FP's fault, but ours for expecting it to do!
No, I think, it’s the Prelude’s fault to define (==) as “floating point equality”. We should us a different identifier like floatingPointEq. (==) is expected to be an equivalence relation. (I think I already said this.)
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Best wishes, Wolfgang _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe