unique_ptr Notes

The class is called unique_ptr because only one unique_ptr at a time can own a dynamically allocated object. By using its overloaded assignment operator or copy constructor, a unique_ptr can transfer ownership of the dynamic memory it manages. The last unique_ptr object that maintains the pointer to the dynamic memory will delete the memory. This makes unique_ptr an ideal mechanism for returning dynamically allocated memory to client code. When the unique_ptr goes out of scope in the client code, the unique_ptr’s destructor destroys the dynamically allocated object and deletes its memory.