# File actionpack/lib/action_controller/mime_type.rb, line 47
      def lookup(string)
        LOOKUP[string]
      end

# File actionpack/lib/action_controller/mime_type.rb, line 51
      def lookup_by_extension(extension)
        EXTENSION_LOOKUP[extension]
      end

# File actionpack/lib/action_controller/mime_type.rb, line 122
    def initialize(string, symbol = nil, synonyms = [])
      @symbol, @synonyms = symbol, synonyms
      @string = string
    end

# File actionpack/lib/action_controller/mime_type.rb, line 70
      def parse(accept_header)
        # keep track of creation order to keep the subsequent sort stable
        list = []
        accept_header.split(/,/).each_with_index do |header, index| 
          params = header.split(/;\s*q=/)
          list << AcceptItem.new(index, *params) unless params.empty?
        end
        list.sort!

        # Take care of the broken text/xml entry by renaming or deleting it
        text_xml = list.index("text/xml")
        app_xml = list.index(Mime::XML.to_s)

        if text_xml && app_xml
          # set the q value to the max of the two
          list[app_xml].q = [list[text_xml].q, list[app_xml].q].max

          # make sure app_xml is ahead of text_xml in the list
          if app_xml > text_xml
            list[app_xml], list[text_xml] = list[text_xml], list[app_xml]
            app_xml, text_xml = text_xml, app_xml
          end

          # delete text_xml from the list
          list.delete_at(text_xml)

        elsif text_xml
          list[text_xml].name = Mime::XML.to_s
        end

        # Look for more specific xml-based types and sort them ahead of app/xml

        if app_xml
          idx = app_xml
          app_xml_type = list[app_xml]

          while(idx < list.length)
            type = list[idx]
            break if type.q < app_xml_type.q
            if type.name =~ /\+xml$/
              list[app_xml], list[idx] = list[idx], list[app_xml]
              app_xml = idx
            end
            idx += 1
          end
        end

        list.map! { |i| Mime::Type.lookup(i.name) }.uniq!
        list
      end

# File actionpack/lib/action_controller/mime_type.rb, line 61
      def register(string, symbol, mime_type_synonyms = [], extension_synonyms = [], skip_lookup = false)
        Mime.send :const_set, symbol.to_s.upcase, Type.new(string, symbol, mime_type_synonyms)

        SET << Mime.send(:const_get, symbol.to_s.upcase)

        ([string] + mime_type_synonyms).each { |string| LOOKUP[string] = SET.last } unless skip_lookup
        ([symbol.to_s] + extension_synonyms).each { |ext| EXTENSION_LOOKUP[ext] = SET.last }
      end

# File actionpack/lib/action_controller/mime_type.rb, line 57
      def register_alias(string, symbol, extension_synonyms = [])
        register(string, symbol, [], extension_synonyms, true)
      end

# File actionpack/lib/action_controller/mime_type.rb, line 147
    def ==(mime_type)
      (@synonyms + [ self ]).any? { |synonym| synonym.to_s == mime_type.to_s } if mime_type
    end

# File actionpack/lib/action_controller/mime_type.rb, line 139
    def ===(list)
      if list.is_a?(Array)
        (@synonyms + [ self ]).any? { |synonym| list.include?(synonym) }
      else
        super
      end
    end

# File actionpack/lib/action_controller/mime_type.rb, line 127
    def to_s
      @string
    end

# File actionpack/lib/action_controller/mime_type.rb, line 131
    def to_str
      to_s
    end

# File actionpack/lib/action_controller/mime_type.rb, line 135
    def to_sym
      @symbol || @string.to_sym
    end

# File actionpack/lib/action_controller/mime_type.rb, line 152
      def method_missing(method, *args)
        if method.to_s =~ /(\w+)\?$/
          mime_type = $1.downcase.to_sym
          mime_type == @symbol || (mime_type == :html && @symbol == :all)
        else
          super
        end
      end