[Haskell-cafe] Quickcheck examples and Data.Word32
Nils Anders Danielsson
nad at cs.chalmers.se
Thu Oct 27 15:11:50 EDT 2005
On Thu, 27 Oct 2005, Sebastian Sylvan <sebastian.sylvan at gmail.com> wrote:
> instance Arbitrary Word32 where
> arbitrary = do c <- arbitrary :: Gen Integer
> return (fromIntegral c)
This definition will usually only generate very small or very large
Word32 values. The reason is the wrapping mentioned elsewhere and the
arbitrary definition for Integer:
arbitrary = sized $ \n -> choose (-fromIntegral n,fromIntegral n)
You would need to manually ask for larger sizes (using
Test.QuickCheck.check with a suitable Config). If a uniform
distribution of Word32s is really needed then I would go with the
other definition.
--
/NAD
More information about the Haskell-Cafe
mailing list