From d1f6ee65547f159cd14de3738e85df114b33edb8 Mon Sep 17 00:00:00 2001
From: danielpeintner <daniel.peintner@gmail.com>
Date: Tue, 12 Sep 2023 10:04:43 +0200
Subject: [PATCH] Update packages/td-tools/src/thing-model-helpers.ts

Co-authored-by: Jan Romann <jan.romann@uni-bremen.de>
---
 packages/td-tools/src/thing-model-helpers.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/td-tools/src/thing-model-helpers.ts b/packages/td-tools/src/thing-model-helpers.ts
index abf28fde4..02cfd73e1 100644
--- a/packages/td-tools/src/thing-model-helpers.ts
+++ b/packages/td-tools/src/thing-model-helpers.ts
@@ -508,7 +508,7 @@ export class ThingModelHelpers {
                 extendedModel.properties = {};
             }
             for (const key in properties) {
-                if (dest.properties && dest.properties[key] !== undefined) {
+                if (dest?.properties[key] !== undefined) {
                     extendedModel.properties[key] = { ...properties[key], ...dest.properties[key] };
                 } else {
                     extendedModel.properties[key] = properties[key];