def interests=(interests)
      raise EOFError, "monitor is closed" if closed?
      raise ArgumentError, "bad interests: #{interests}" unless [:r, :w, :rw, nil].include?(interests)

      @interests = interests
    end
def interests=(interests)
      raise EOFError, "monitor is closed" if closed?
      raise ArgumentError, "bad interests: #{interests}" unless [:r, :w, :rw, nil].include?(interests)

      @interests = interests
    end
:nodoc:
 Replace the existing interest set with a new one

 @param interests [:r, :w, :rw, nil] I/O readiness we're interested in (read/write/readwrite)

 @return [Symbol] new interests