On 28-Jul-1998, Simon L Peyton Jones <[EMAIL PROTECTED]> wrote:
> "S.D.Mechveliani" <[EMAIL PROTECTED]> wrote:
> > This may occur a stupid question, but
> > why Haskell allows the `newtype' derivation only for the standard
> > classes?
> > Why not support declarations like
> >
> > newt
> class (Ring r,AddGroup (m r)) => RightModule m r
> where
> cMul :: m r -> r -> m r
> -- "vector" (m r) multiplied by "coefficient" r'
>
> Haskell rejects this (m r) in the context. Could Haskell-2 allow it?
Yes. See http://www.dcs.gla.ac.uk/~simonpj/multi-p
Here are some questions and suggestions for Haskell-2.
They concern the
* (composed) constructs in a class or instance context,
* identity constructor expression
* deriving "all" for `newtype'
* ambiguity resolving via first argument in a class operation
In mathematics, the fir
S.D.Mechveliani wrote:
Remark and question on the ambiguity problem
M.Jones & S.P.Jones paper "...Exploration of Design Space."
E. Meijer is also an author of this paper.
Matrix multiplication:
* :: Matrix a -> Matrix b -> Matrix c
On Mon, 27 Jul 1998, S.D.Mechveliani wrote:
> Obstacle 2:
>
> Haskell rejects this `=> RightModule r r'
>
> How can we express the meaning
>... RightModule m r where m is the identical constructor
> (m
