On April 5, 2007 1:04 PM Waldek Hebisch wrote: > > Bill Page wrote: > > > > If Set is implemented by sorting the linear order cannot be > > domain specific since there certainly are domains from which > > we might wish to form finite sets for which no "natural" order > > can be defined, e.g. the domain Any. But I think it is always > > possible to define some lexical ordering over the members of > > all domains For example, the Axiom interpreter contains the > > Lisp function LEXGREATERP in > > > > src/interp/ggreater.lisp.pamphlet > > > > For the implementation of Set using sorting all that is required > > is that the ordering be constant within an Axiom session. > > > > 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? > Producing order is not very hard. Producing "from outside" > order which agrees with equality seem to be expensive (I am > affraid that you need to store all domain elements in a hash > table). That is why I am saying about design bug. Why? > ... Regards, Bill Page. _______________________________________________ Axiom-developer mailing list [email protected] http://lists.nongnu.org/mailman/listinfo/axiom-developer
