A good way to understand copy-control members and constructors is to define a simple class...

A good way to understand copy-control members and constructors is to define a simple class with these members in which each member prints its name:

struct X {    X() {std::cout << "X()" << std::endl;}    X(const X&) {std::cout << "X(const X&)" << std::endl;}};

Add the copy-assignment operator and destructor to X and write a program using X objects in various ways: Pass them as nonreference and reference parameters; dynamically allocate them; put them in containers; and so forth. Study the output until you are certain you understand when and why each copy-control member is used. As you read the output, remember that the compiler can omit calls to the copy constructor.