# File lib/drb/drb.rb, line 777
    def uri_option(uri, config, first=true)
      @protocol.each do |prot|
        begin
          uri, opt = prot.uri_option(uri, config)
          # opt = nil if opt == ''
          return uri, opt
        rescue DRbBadScheme
        end
      end
      if first && (config[:auto_load] != false)
        auto_load(uri, config)
        return uri_option(uri, config, false)
      end
      raise DRbBadURI, 'can\'t parse uri:' + uri
    end