dvde: > Dear Haskellers, > > I just want to share an observation. I had to convert a Double to a > Float value in an inner loop of an application, and I used somethin like > this: > > xf = (fromRational $ toRational xd) :: Float > > The program works on windows but it did not on OSX - it was too slow. > Now, after big headaches and much frustration, I replaced the code above > with this line (why didn't I come up with this earlier?): > > xf = double2Float xd > > and now everything works just fine. > > I am not really surprised by the speed-up (and no-one should be), but I > am still surprised how often such kinds of unobvious problems occur > while programming in Haskell. So I write this email just to remind me > and you to look out for such pitfalls.
There's no rewrite rule for this optimization. There's a ticket though with some of the solutions. -- Don _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
