import { MetricId } from './types';
type OnEndCallback = (result: number) => void;
type OnLogCallback = (result: number) => void;
export declare namespace MainThreadBenchmark {
    const engage: (params: {
        metricId: MetricId;
        onEnd?: OnEndCallback;
        onLog?: OnLogCallback;
    }) => void;
    const isRunning: (metricId: MetricId) => boolean;
    const hasStarted: (metricId: MetricId) => boolean;
    const start: (metricId: MetricId) => void;
    const end: (metricId: MetricId) => void;
    const log: (params: {
        metricId: MetricId;
        value: any;
    }) => void;
    const clear: () => void;
}
export {};
