# File lib/core/message.rb, line 196
    def ttl=(time)
      raise TypeError.new("invalid ttl: #{time}") if not time.is_a?(Numeric)
      raise RangeError.new("ttl out of range: #{time}") if ((time.to_i < 0))
      Cproton.pn_message_set_ttl(@impl, time.floor)
    end