code: func (q *TransmitLimitedQueue) deleteItem(cur *limitedBroadcast) {
  	_ = q.tq.Delete(cur)
  	if cur.name != "" {
  		delete(q.tm, cur.name)
  	}
  
  	if q.tq.Len() == 0 {
  		// At idle there's no reason to let the id generator keep going
  		// indefinitely.
  		q.idGen = 0
  	}
  }
docs: // deleteItem removes the given item from the overall datastructure. You
  // must already hold the mutex.