1  import { ReportHandler } from 'web-vitals';
 2  
 3  const reportWebVitals = (onPerfEntry?: ReportHandler) => {
 4    if (onPerfEntry && onPerfEntry instanceof Function) {
 5      import('web-vitals').then(({ getCLS, getFID, getFCP, getLCP, getTTFB }) => {
 6        getCLS(onPerfEntry);
 7        getFID(onPerfEntry);
 8        getFCP(onPerfEntry);
 9        getLCP(onPerfEntry);
10        getTTFB(onPerfEntry);
11      });
12    }
13  };
14  
15  export default reportWebVitals;