Deleting dynamically allocated objects with private destructors

Question

So I came across a code snippet which demonstrated that if we want forced dynamic allocation of any class object, we should make its destructor private.

I tried that and yes it doesn't allow one to instantiate object on stack. But when I instantiated a dynamically allocated instance and tried deleting the object (or it would cause leak) - I kept on getting warning about destructor being private.

How can I properly manage memory of a dynamically allocated object which has a private destructor?

Answer 1

Like accessing any other private member function, you must do it in a member or a friend function. An example:

class foo {
    ~foo(){}
public:
    static void del(const foo* ptr)
    {
        delete ptr;
    }
};

Or even better, force the client to use smart pointer:

class foo {
    ~foo(){}
    struct deleter {
        void operator()(const foo* ptr)
        {
            delete ptr;
        }
    };
public:
    static std::unique_ptr<foo, deleter> make(/*args*/)
    {
        return {new foo(/*args*/), {}};
    }
};