PlaceOrder3.cs

using System;
using ValueObject;

namespace ValueObject3
{
    public record PlaceOrderCommand(Guid CustomerId, string ProductSku, int Quantity, PlaceOrderCurrency Currency)
    {
        public PlaceOrderCommand(Guid customerId, string productSku)
            : this(customerId, productSku, 1, PlaceOrderCurrency.Default) { }

        public PlaceOrderCommand(Guid customerId, string productSku, Currency currency)
            : this(customerId, productSku, 1, new PlaceOrderCurrency(currency.Symbol)) { }

        public PlaceOrderCommand(Guid customerId, string productSku, int quantity)
            : this(customerId, productSku, quantity, PlaceOrderCurrency.Default) { }
    }

    public record PlaceOrderCurrency(string Symbol)
    {
        public static PlaceOrderCurrency Default => new("USD");
    };
}