copyWith method
Implementation
UnitInterval copyWith({BigInt? numerator, BigInt? denominator}) {
  return UnitInterval(
      numerator: numerator ?? this.numerator,
      denominator: denominator ?? this.denominator);
}UnitInterval copyWith({BigInt? numerator, BigInt? denominator}) {
  return UnitInterval(
      numerator: numerator ?? this.numerator,
      denominator: denominator ?? this.denominator);
}