bugfix for ts

Author: terapyon

package.json

@@ -94,7 +94,7 @@
     "@lumino/widgets": "pinned to the latest Lumino 1.x release"
   },
   "jupyterlab": {
-    "extension": "lib/plugin",
+    "extension": true,
     "mimeExtension": true,
     "outputDir": "net_vis/labextension/",
     "sharedPackages": {

src/graph.ts

@@ -68,7 +68,11 @@ function Graph(svg: any, { nodes, links }: { nodes: Node[]; links: Link[] }) {
     .forceSimulation(nodes)
     .force(
       'link',
-      d3.forceLink(links).id((d: any) => (d as Node).id.toString()),
+      d3.forceLink(links).id((d: any) => {
+        // Safely access id with null check
+        const node = d as Node;
+        return node && node.id ? String(node.id) : '';
+      }),
     )
     .force('charge', d3.forceManyBody())
     .force('center', d3.forceCenter(400, 400));

src/index.ts

@@ -1,5 +1,9 @@
 // Copyright (c) Manabu TERADA
 // Distributed under the terms of the Modified BSD License.
 
+// Export plugin as default for JupyterLab to load
+export { default } from './plugin';
+
+// Export other modules for backward compatibility
 export * from './version';
 export * from './widget';