removing constraints

[Ross Paterson]

On Fri, Jan 09, 2015 at 10:29:43AM -0500, David Feuer wrote:
> 
> On Jan 9, 2015 10:25 AM, "Ross Paterson" <R.Paterson at city.ac.uk> wrote:
> > These constraints are not needed by the GHC implementations, but might be
> > needed for other possible implementations, so in a sense the changes are
> > leaking the GHC implementations.  This seems most clear in the Functor
> > and Foldable instances for Array, and elems.  Portable implementations
> > of these will require the Ix constraint -- I think it should be restored.
> 
> Agreed.
> 
> > The other cases are more arguable.  For example the change to Data.Ratio
> > declares that the pair is kept in reduced form, but one could argue that
> > requiring that is no bad thing.
> 
> Disagreed. However, some have argued convincingly that the Ratio type as it
> stands makes little sense anyway.

I'm not clear what you're disagreeing with here, since my original statement
was equivocal.

That also leaves the question of the Ix constraint on bounds.  Should it be
removed, and if so should it also be removed from the bounds methods in the
IArray and MArray classes?