In this recipe, we will learn how to make a class move-only. A great example of the difference between a copy and a move is the difference between std::unique_ptr and std::shared_ptr.

The point of std::unique_ptr is to enforce a single owner for dynamically allocated types while std::shared_ptr allows for multiple owners of dynamically allocated types. Both allow the user to move the contents of a pointer type from one instantiation to another, but only std::shared_ptr allows the user to make a copy of the pointer (as copying the pointer would create more than one owner).

In this recipe, we will use these two classes to show how to make a move-only class and to show why this type of class is used so heavily in C++ (as most of the time we wish to move and not copy).