# File lib/sup/source.rb, line 192
  def add_source source
    @source_mutex.synchronize do
      raise "duplicate source!" if @sources.include? source
      @sources_dirty = true
      max = @sources.max_of { |id, s| s.is_a?(DraftLoader) || s.is_a?(SentLoader) ? 0 : id }
      source.id ||= (max || 0) + 1
      ##source.id += 1 while @sources.member? source.id
      @sources[source.id] = source
    end
  end