/**
 * Owns monotonically increasing request identities used to ignore stale work.
 */
export declare class RequestSequence {
    private currentSequence;
    /**
     * Starts a new owned request and invalidates all previous identities.
     *
     * @returns Identity owned by the new request.
     */
    next(): number;
    /**
     * Invalidates the currently owned request without starting asynchronous work.
     */
    invalidate(): void;
    /**
     * Checks whether a request identity is still owned by this sequence.
     *
     * @param requestSequence - Identity captured when work started.
     * @returns Whether that work may still update state.
     */
    isCurrent(requestSequence: number): boolean;
}