type ThrottleOption = {
    /** drop=true: Drop chunks by interval, will ensure last item emit by default. set keepLast=false to drop last */
    drop?: boolean;
    /**
     * drop=true: Drop chunks by interval, will ensure last item emit by default. set keepLast=false to drop last
     * has no effect when drop=false
     */
    keepLast?: boolean;
};
/**
 * ```ts
 * drop=true: Drop chunks by interval, will ensure last item emit by default.
 * set keepLast=false to drop last
 *
 * @example
 * if you dont want item drops, please use forEach to limit speed
 * sth like:
 * sflow().forEach(sleep(1000)).forEach(sleep(1000)).log().done()
 */
export declare function throttles<T>(interval: number, { drop, keepLast }?: ThrottleOption): TransformStream<T, T>;
export {};