web-vitals
Version:
Easily measure performance metrics in JavaScript
12 lines (11 loc) • 625 B
TypeScript
import { FIDMetricWithAttribution, ReportOpts } from '../types.js';
/**
* Calculates the [FID](https://web.dev/articles/fid) value for the current page and
* calls the `callback` function once the value is ready, along with the
* relevant `first-input` performance entry used to determine the value. The
* reported value is a `DOMHighResTimeStamp`.
*
* _**Important:** since FID is only reported after the user interacts with the
* page, it's possible that it will not be reported for some page loads._
*/
export declare const onFID: (onReport: (metric: FIDMetricWithAttribution) => void, opts?: ReportOpts) => void;