Method plus

packages/graph/src/TemporalTypes.ts:1347–1354

* Add this duration to another duration.

(other: DurationValue)

   * Add this duration to another duration.
   */
  public plus(other: DurationValue): DurationValue {
    return new DurationValue(
      this.#months + other.#months,
      this.#days + other.#days,
      this.#seconds + other.#seconds,
      this.#nanoseconds + other.#nanoseconds,
    );
  }

  /**
   * Subtract another duration from this duration.