Data/Floating/Instances.hs

   1 {-
   2  - Copyright (C) 2009 Nick Bowler.
   3  -
   4  - License BSD2:  2-clause BSD license.  See LICENSE for full terms.
   5  - This is free software: you are free to change and redistribute it.
   6  - There is NO WARRANTY, to the extent permitted by law.
   7  -}
   8
   9 module Data.Floating.Instances where
  10
  11 import qualified Prelude
  12 import Prelude hiding (round, floor, ceiling, truncate)
  13 import Data.Floating.Types.Core
  14 import Data.Ratio
  15
  16 instance Integral a => Roundable (Ratio a) where
  17     toIntegral = Just . fst . properFraction
  18     round x
  19         | abs frac >= 1%2 = int%1 + signum frac
  20         | otherwise       = int%1
  21         where (int, frac) = properFraction x