# File lib/etherpad-lite/models/pad.rb, line 49
    def initialize(instance, id, options={})
      @instance = instance
      @id = id.to_s
      if options[:groupID]
        @group_id = options[:groupID]
        @id = "#{@group_id}$#{@id}" unless @id =~ Group::GROUP_ID_REGEX
      end
      @group = options[:group]
      @rev = options[:rev]
    end