OptionInspection.cs

private Result<Unit> ApplyDiscountWhenAvailable(Option<string> discountCode)
{
  return discountCode.Match(Some: ApplyDiscount,
                            None: () => Unit.Default);
}

private Result<Unit> ApplyDiscount(string discountCode)
{
    //mimic applying discount code (whatever that means)
    return Unit.Default;
}