This requires
{-# OPTIONS_GHC -fallow-undecidable-instances #-}
but since I'm using -fglasgow-exts in a lot of places I'm wondering
if adding undecidable instances would be a bad habit. I guess not...
not until I shoot myself in the foot :-).
Any explanation of undecidable instances, the good and the bad?
Joel
On Oct 27, 2005, at 6:49 PM, Bryn Keller wrote:
How about this?
class ArbitraryDefault a where {}
instance (Integral a, Bounded a, ArbitraryDefault a) => Arbitrary a
where
arbitrary = arbitraryBound
coarbitrary a = error "Not implemented"
instance ArbitraryDefault Word16 instance ArbitraryDefault Word32
instance ArbitraryDefault Word64
--
http://wagerlabs.com/
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