-- | Constructs a unit of volume from a unit of length, taking the volume of a cube whose sides are that length.
--
-- >>> 64 *~ cubic meter == (4 *~ meter) ^ pos3
-- True
cubic  :: (Fractional a, Typeable m) => Unit m DLength a -> Unit 'NonMetric DVolume a
cubic  x = x ^ pos3
cubic  :: (Fractional a, Typeable m) => Unit m DLength a -> Unit 'NonMetric DVolume a
cubic  x = x ^ pos3
cubic  x = x ^ pos3