One might expect a == (a/b)*b and other common arithmetic formulas to hold for division?
/Jonas On 31 May 2010 14:32, Maciej Piechotka <uzytkown...@gmail.com> wrote: > I started to wonder what is the difference between div and / so they are > 2 separate symbols. > > div: > Take a Integral divide and round (down) > > (/): > Take a Fractional divide and usually round > > In some applications I would like to use any of those but it is not > possible. Is this unification taken into account while reworking numeric > classes? > > I.e. why not: > > class Num a => Divisable a where > (/) :: a -> a -> a > > class (Real a, Enum a, Divisable a) => Integral a where > quot :: a -> a -> a > rem :: a -> a -> a > div = (/) > mod :: a -> a -> a > x `quotRem` y = (x `quot` y, x `rem y) > x `divMod` y = (x `div` y, x `mod` y) > toInteger :: a -> Integer > > class Divisable a => Fractional a where > recip = (1/) :: a -> a > fromRational :: Rational -> a > > (Example does not take into account other refactoring) > > Regards > > PS. Why is Fd/cPid etc. Integral or even Num? > What does (stdin + stderr) `mod` stdout mean (result will be stdin). > > _______________________________________________ > Haskell-Cafe mailing list > Haskell-Cafe@haskell.org > http://www.haskell.org/mailman/listinfo/haskell-cafe > > _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
