Version: 0.1.00.2.00.2.10.2.20.2.30.2.41.0.01.0.11.1.01.1.11.1.22.0.0-beta.02.0.0-beta.12.0.0-beta.22.0.02.0.12.1.02.1.12.1.22.1.32.1.43.0.0-beta.03.0.0-beta.13.0.0-beta.23.0.0-rc.03.0.03.0.13.0.23.0.33.0.43.1.03.1.1-soft-navs3.1.1-soft-navs-13.1.1-soft-navs-23.1.1-soft-navs-33.1.1-soft-navs-43.1.1-soft-navs-53.1.13.3.0-soft-navs-63.3.03.3.1-soft-navs-73.3.1-types3.3.1-types-23.3.13.3.2-soft-navs-83.3.23.4.0-soft-navs-93.4.03.5.0-soft-navs-103.5.0-soft-navs-113.5.0-soft-navs-123.5.0-soft-navs-133.5.0-soft-navs-143.5.03.5.1-soft-navs-153.5.13.5.2-soft-navs-163.5.24.0.0-beta.04.0.0-beta.14.0.0-beta.24.0.0-beta.34.0.0-rc.04.0.04.0.14.1.04.1.14.2.0-debug.04.2.04.2.14.2.2-soft-navs4.2.2-soft-navs-24.2.24.2.3-soft-navs4.2.34.2.45.0.0-rc.0
import { MetricRatingThresholds, ReportOpts, TTFBMetric } from './types.js';
/** Thresholds for TTFB. See https://web.dev/articles/ttfb#what_is_a_good_ttfb_score */
export declare const TTFBThresholds: MetricRatingThresholds;
/**
* Calculates the [TTFB](https://web.dev/articles/ttfb) value for the
* current page and calls the `callback` function once the page has loaded,
* along with the relevant `navigation` performance entry used to determine the
* value. The reported value is a `DOMHighResTimeStamp`.
*
* Note, this function waits until after the page is loaded to call `callback`
* in order to ensure all properties of the `navigation` entry are populated.
* This is useful if you want to report on other metrics exposed by the
* [Navigation Timing API](https://w3c.github.io/navigation-timing/). For
* example, the TTFB metric starts from the page's [time
* origin](https://www.w3.org/TR/hr-time-2/#sec-time-origin), which means it
* includes time spent on DNS lookup, connection negotiation, network latency,
* and server processing time.
*/
export declare const onTTFB: (onReport: (metric: TTFBMetric) => void, opts?: ReportOpts) => void;