Ralf Hemmecke writes: > William Sit wrote: > > > For example, if I have a constructor that requires an integral domain R as > > a parameter, and I constructed in the package the quotient field of R, as > > you may suggest as an explicit way to achieve efficiency, then the package > > will FAIL if R is actually a field (you can consider this as a bug if you > > like), even though a field IS an integral domain, mathematically.
Why would it fail? I don't think it does, in fact. However, if you are going to apply FRAC you can simply ask whether the domain is a Field. On the other hand, given a Field to ask whether it is a QuotientField is a question that I consider quite important. However, the desirable query if R has QuotientField S thus defining S is, I think, quite difficult to implement sensibly. Throughout Axiom, this effect is obtained by adding another parameter to the Package/Domain signature like: MyPackage(F: Field, S: IntegralDomain): ... if F is Fraction S then Martin _______________________________________________ Axiom-developer mailing list [email protected] http://lists.nongnu.org/mailman/listinfo/axiom-developer
