nature-symbol">: </span><a href="../classes/_exchanges_exchangefeed_.exchangefeed.html" class="tsd-signature-type">ExchangeFeed</a>, product<span class="tsd-signature-symbol">: </span><span class="tsd-signature-type">string</span>, onlyOnce<span class="tsd-signature-symbol">?: </span><span class="tsd-signature-type">boolean</span><span class="tsd-signature-symbol">)</span><span class="tsd-signature-symbol">: </span><a href="../classes/_core_triggers_.trigger.html" class="tsd-signature-type">Trigger</a><span