diff --git a/broker.ts b/broker.ts
index e7a0a4b..16ecfef 100644
--- a/broker.ts
+++ b/broker.ts
@@ -126,6 +126,12 @@ function parse(input: string): Node {
 
 function render(node: Node): string {
 
+  if (typeof node.type == "undefined") {
+    console.log("...finished...")
+
+    return "";
+  }
+
   console.log("Render node " + node.type);
 
   var outputHTML: string = "";