replacing method
Returns a new TimeOfDay with the hour and/or minute replaced.
Implementation
TimeOfDay replacing({ int? hour, int? minute }) {
assert(hour == null || (hour >= 0 && hour < hoursPerDay));
assert(minute == null || (minute >= 0 && minute < minutesPerHour));
return TimeOfDay(hour: hour ?? this.hour, minute: minute ?? this.minute);
}