typescript! yay! (pain.)

src/reportWebVitals.ts

@@ -0,0 +1,12 @@
+import { type MetricType, onCLS, onFCP, onLCP, onTTFB } from "web-vitals";
+
+const reportWebVitals = (onPerfEntry?: (metric: MetricType) => void): void => {
+  if (onPerfEntry && onPerfEntry instanceof Function) {
+    onCLS(onPerfEntry);
+    onFCP(onPerfEntry);
+    onLCP(onPerfEntry);
+    onTTFB(onPerfEntry);
+  }
+};
+
+export default reportWebVitals;