type Cancellor = (catchPayload: unknown) => void;
type CancellablePromise = Promise<void> & {
    /**
     * Rejects the promise with optional `catchPayload`.
     *
     * Default value for `catchPayload` is `new Error('cancelled')`
     */
    cancel: Cancellor;
};
/**
 * Returns a Promise that resolves after `duration` milliseconds
 *
 * The returned Promise has a `.cancel()` method to reject the promise.
 */
export declare const wait: (duration: number) => CancellablePromise;
/**
 * Returns a "then"-function that adds lag/delay to a promise chain,
 * passing the promise payload through.
 */
export declare const addLag: (duraction: number) => <T>(payload: T) => Promise<T>;
export {};