Re: Using newtypes or any data with unboxed Vectors

On Sun, 12 Jul 2015, Ken Bateman wrote:

newtype SmallPos = Pos Int     deriving (Eq, Ord, Show)

smallPos :: Int -> SmallPos smallPos x | x > 0 && x < 100 = Pos x            | otherwise = error "bad SmallPos"

instance UnboxEquivalent SmallPos where     type UnboxEquiv SmallPos = Word8     toUnbox (Pos x) = fromIntegral x     fromUnbox x = (Pos (fromIntegral x))

I assume that something like this is already possible with the Unbox type class, but currently I cannot see how. :-(