addYears method

Jalali addYears (
  1. int years
)

add years to this date

throws on null argument

non-null

Implementation

Jalali addYears(int years) {
  ArgumentError.checkNotNull(years, 'years');

  if (years == 0) {
    return this;
  } else {
    return Jalali(year + years, month, day);
  }
}