Re: [Axiom-developer] Set Any and SXHASH

[Waldek Hebisch]

> On April 5, 2007 1:25 PM Waldek Hebisch wrote:
> > ...
> > > > 
> > > > You need an order which is consistent with equality.
> > > 
> > > I agree.
> > > 
> > > > Since equality is domain-specific you need also domian-
> > > > specific order.  I agree that we do not have one handy.
> > > 
> > > I do not agree. What do you think is wrong with LEXGREATERP
> > > for this purpose?
> > > 
> > 
> > AFAICS LEXGREATERP compares representations, completly ignoring
> > equality from domain.
> > 
> 
> Yes. Why do you say that this would not be consistent with
> domain equality?
>

Domain elements may be mathematically equal but have different
representations.  AFAICS this happens for example for general
fractions.
 
> What problems would occur if elements of all finite sets
> were ordered according to this ordering?
> 


We may miss duplicates and declare equal sets as unequal.

-- 
                              Waldek Hebisch
address@hidden