def desc
      fsym = FieldSymbol.new(self, respond_to?(:desc?) ? !desc? : true)
      fsym.type = respond_to?(:type) ? type : nil
      fsym
    end
def desc
      fsym = FieldSymbol.new(self, respond_to?(:desc?) ? !desc? : true)
      fsym.type = respond_to?(:type) ? type : nil
      fsym
    end
Set a field to be a descending field. This only makes sense in sort
 specifications.