[rabbitmq-discuss] Delete a long-time-empty queue?

[RabbitMqUser]

I noticed that:

auto-delete will delete queue when count of consumers decrease to 0;
Queue TTL will delete queue when non-consumed time exceed TTL;

Even though the queue that been deleted is not empty! 
So my question is, Is there any chance we lost messages when use 
auto-delete or Queue TTL? 
How can I delete a queue based on time of it's empty since, other that time 
of non-consumed?
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