# File lib/net/dns/rr/types.rb, line 121
        def initialize(type)
          case type
          when String
            # type in the form "A" or "NS"
            new_from_string(type.upcase)
          when Fixnum
            # type in numeric form
            new_from_num(type)
          when nil
            # default type, control with Types.default=
            @str = TYPES.invert[@@default]
            @num = @@default
          else
            raise ArgumentError, "Wrong type class: #{type.class}"
          end
        end