Practical example where Tuple can be used in .Net 4.0?

Question

I have seen the Tuple introduced in .Net 4 but I am not able to imagine where it can be used. We can always make a Custom class or Struct.

Answer 1

Changing shapes of objects when you need to send them across wire or pass to different layer of application and multiple objects get merged into one:

Example:

var customerDetails = new Tuple>(mainCustomer, new List
 {mainCustomerAddress}).ToCustomerDetails();

ExtensionMethod:

public static CustomerDetails ToCustomerDetails(this Tuple> customerAndAddress)
    {
        var mainAddress = customerAndAddress.Item2 != null ? customerAndAddress.Item2.SingleOrDefault(o => o.Type == "Main") : null;
        var customerDetails = new CustomerDetails
        {
            FirstName = customerAndAddress.Item1.Name,
            LastName = customerAndAddress.Item1.Surname,
            Title = customerAndAddress.Item1.Title,
            Dob = customerAndAddress.Item1.Dob,
            EmailAddress = customerAndAddress.Item1.Email,
            Gender = customerAndAddress.Item1.Gender,
            PrimaryPhoneNo = string.Format("{0}", customerAndAddress.Item1.Phone)
        };

        if (mainAddress != null)
        {
            customerDetails.AddressLine1 =
                !string.IsNullOrWhiteSpace(mainAddress.HouseName)
                    ? mainAddress.HouseName
                    : mainAddress.HouseNumber;
            customerDetails.AddressLine2 =
                !string.IsNullOrWhiteSpace(mainAddress.Street)
                    ? mainAddress.Street
                    : null;
            customerDetails.AddressLine3 =
                !string.IsNullOrWhiteSpace(mainAddress.Town) ? mainAddress.Town : null;
            customerDetails.AddressLine4 =
                !string.IsNullOrWhiteSpace(mainAddress.County)
                    ? mainAddress.County
                    : null;
            customerDetails.PostCode = mainAddress.PostCode;
        }
...
        return customerDetails;
    }