declare type QueryParamChangeCallback = (isPresent: boolean) => void;
export declare class QueryParamPresenceWatcher {
    private static WatchTimeoutMs;
    private previousValue;
    private timers;
    /**
     * Check if query parameter is present in the current page URL.
     * Query parameter value is ignored, only presence is checked.
     *
     * @param {string} queryParam
     * @returns {boolean}
     */
    static isQueryParamPresent(queryParam: string): boolean;
    watch: (queryParam: string, onChange: QueryParamChangeCallback) => void;
    unwatchAll: () => void;
}
export {};