static LPair<Concept.Ref, S> scanConceptForRefsWithFieldNames(Concept c) {
  LPair<Concept.Ref, S> refs = new L;
  if (c != null) for (S field, O o : objectToMap(c)) {
    if (o cast Concept.Ref)
      refs.add(pair(o, field));
    else if (o cast Concept.RefL)
      for (i, O ref : o.l)
        refs.add(pair((Concept.Ref) ref, field + "[" + (i+1) + "]");
  }
  ret refs;
}