 
       # months of last year
       last_year = _.last(years)
-      for idx,v in chat_data()[room][last_year]
+      for idx,v of chat_data()[room][last_year]
         links.push "#{last_year}/#{idx}" if v
 
       # days of last month
       last_month = chat_data()[room][last_year].length - 1
-      for idx,v in chat_data()[room][last_year][last_month]
+      for idx,v of chat_data()[room][last_year][last_month]
         links.push "#{last_year}/#{last_month}/#{idx}" if v
 
     send_links res, "#{base_path}/#{room}", links

    year = parseInt req.params.year
    month = parseInt(req.params.month) - 1
    if chat_data()[room]?[year]?[month]?
      links.push "#{idx}" if v for idx,v in chat_data()[room][year][month]
    send_links res, "#{base_path}/#{room}/#{year}/#{month}", links

  robot.router.get "/#{base_path}/:room/:year/:month/:date", (req, res) ->

    room = req.params.room
    year = parseInt req.params.year
    if chat_data()[room]?[year]?
      links.push "#{idx}" if v for idx,v of chat_data()[room][year]
    send_links res, "#{base_path}/#{room}/#{year}", links

  robot.router.get "/#{base_path}/:room/:year/:month", (req, res) ->
