1import { createDuration } from './create';
2
3function addSubtract(duration, input, value, direction) {
4    var other = createDuration(input, value);
5
6    duration._milliseconds += direction * other._milliseconds;
7    duration._days += direction * other._days;
8    duration._months += direction * other._months;
9
10    return duration._bubble();
11}
12
13// supports only 2.0-style add(1, 's') or add(duration)
14export function add(input, value) {
15    return addSubtract(this, input, value, 1);
16}
17
18// supports only 2.0-style subtract(1, 's') or subtract(duration)
19export function subtract(input, value) {
20    return addSubtract(this, input, value, -1);
21}