Question

C++ does not support nested function. Say I have function a and b, I want to guarantee that only a can call b, and nobody else can, is there a way of doing so?

Answer 1

No, but you can always create a function-level class. For example:

void MyFunction() {

    class InnerClass {
    public:
        static void InnerFunction() {
        }
    };

    InnerClass::InnerFunction();
    InnerClass::InnerFunction();
    // ...

};