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

I don't like the abuse of them, since they produce code that doesn't explain itself, but they're awesome to implement on-the-fly compound keys, since they implement IStructuralEquatable and IStructuralComparable (to use both for lookup and ordering purposes).

And they combine all of their items' hashcodes, internally; for example, here is Tuple's GetHashCode (taken from ILSpy):

    int IStructuralEquatable.GetHashCode(IEqualityComparer comparer)
    {
        return Tuple.CombineHashCodes(comparer.GetHashCode(this.m_Item1), comparer.GetHashCode(this.m_Item2), comparer.GetHashCode(this.m_Item3));
    }