# File lib/sinatra/link_header.rb, line 84
    def link(*urls)
      opts          = urls.last.respond_to?(:to_hash) ? urls.pop : {}
      opts[:rel]    = urls.shift unless urls.first.respond_to? :to_str
      options       = opts.map { |k, v| " #{k}=#{v.to_s.inspect}" }
      html_pattern  = "<link href=\"%s\"#{options.join} />"
      http_pattern  = ["<%s>", *options].join ";"
      link          = (response["Link"] ||= "")

      urls.map do |url|
        link << "\n" unless link.empty?
        link << (http_pattern % url)
        html_pattern % url
      end.join "\n"
    end