def reject_all_values_if_none(source_list)
      if source_list.length > 1
        source_list.reject { |value| value == NONE }
      else
        source_list
      end
    end
def reject_all_values_if_none(source_list)
      if source_list.length > 1
        source_list.reject { |value| value == NONE }
      else
        source_list
      end
    end
Discard any 'none' values if more directives are supplied since none may override values.