code: func NewTransferPoller(setts *account.Settings, filter ReceiveEventFilter, interval time.Duration) *TransferPoller {
  	if setts.EventMachine == nil {
  		setts.EventMachine = &event.DiscardEventMachine{}
  	}
  	if filter == nil {
  		filter = NewPerTailReceiveEventFilter(true)
  	}
  	poller := &TransferPoller{
  		setts: setts, receiveEventFilter: filter,
  	}
  	poller.syncTimer = util.NewSyncIntervalTimer(interval, poller.pollTransfers, func(err error) {
  		poller.setts.EventMachine.Emit(err, event.EventError)
  	})
  	return poller
  }
docs: // NewTransferPoller creates a new TransferPoller. If the interval is set to 0, the TransferPoller will only
  // poll through Poll().