# File lib/twitter/core_ext/hash.rb, line 37
  def merge_users!(user_ids_or_screen_names)
    user_ids, screen_names = [], []
    user_ids_or_screen_names.flatten.each do |user_id_or_screen_name|
      case user_id_or_screen_name
      when Integer
        user_ids << user_id_or_screen_name
      when String
        screen_names << user_id_or_screen_name
      end
    end
    self[:user_id] = user_ids.join(',') unless user_ids.empty?
    self[:screen_name] = screen_names.join(',') unless screen_names.empty?
    self
  end