compareTo method
Compare dates
Implementation
@override
int compareTo(Gregorian other) {
if (year != other.year) {
return year > other.year ? 1 : -1;
}
if (month != other.month) {
return month > other.month ? 1 : -1;
}
if (day != other.day) {
return day > other.day ? 1 : -1;
}
return 0;
}