622 {
625 const SourceRing &R1 =
627 const TargetRing &S1 =
629
630 typename SourceRing::Element fR1(R1);
631 typename TargetRing::Element gS1(S1);
632
633 R1.from_ring_elem(fR1, fR);
634 bool retval =
mypromote(R1, S1, fR1, gS1);
635 if (retval) S1.to_ring_elem(resultS, gS1);
636 return retval;
637 }
bool mypromote(const RingR &R, const RingS &S, const typename RingR::ElementType &fR, typename RingS::ElementType &result_fS)