diff --git a/examples/ws2/cancel_all.js b/examples/ws2/cancel_all.js
index 92ad86c4..010ec152 100644
--- a/examples/ws2/cancel_all.js
+++ b/examples/ws2/cancel_all.js
@@ -27,7 +27,7 @@ module.exports = runExample({
     return debug('no orders to cancel')
   }
 
-  const orders = _isEmpty(filterByMarket)
+  const orders = (!filterByMarket)
     ? allOrders
     : allOrders.filter(o => o.symbol === filterByMarket)