On Saturday 23 October 2010 22:53:32, Alexey Khudyakov wrote: > > type family Scalar :: * -> * > > > > class Additive v => LeftModule v where > > (*^) :: Scalar v -> v -> v > > > > class Additive v => RightModule v where > > (^*) :: v -> Scalar v -> v > > Could you give some example of data type for which (*^) ≠ flip (^*)? > I couldn't imagine one.
Take any noncommutative ring R (quaternions for example) and consider the space R^n as a) a left R-module and b) a right R-module. _______________________________________________ Haskell-Cafe mailing list [email protected] http://www.haskell.org/mailman/listinfo/haskell-cafe
