import type { IsoDuration } from '../../domain.objects/IsoDuration';
import type { IsoDurationShape } from '../../domain.objects/IsoDurationShape';
/**
 * .what = sums multiple iso durations into one
 * .why = enables duration arithmetic for total elapsed time
 */
export declare function sumDurations(durations: IsoDuration[]): IsoDurationShape;
export declare function sumDurations(durations: IsoDuration[], options: {
    as: keyof IsoDurationShape;
}): IsoDurationShape;
export declare function sumDurations(...durations: IsoDuration[]): IsoDurationShape;