Calling private method in C++

Question

This is purely a theoretical question, I know that if someone declares a method private, you probably shouldn't call it. I managed to call private virtual methods and change private members for instances, but I can't figure out how to call a private non-virtual method (without using __asm). Is there a way to get the pointer to the method? Are there any other ways to do it?

EDIT: I don't want to change the class definition! I just want a hack/workaround. :)

Answer 1

See my blog post. I'm reposting the code here

template<typename Tag> struct result {   /* export it ... */   typedef typename Tag::type type;   static type ptr; };  template<typename Tag> typename result<Tag>::type result<Tag>::ptr;  template<typename Tag, typename Tag::type p> struct rob : result<Tag> {   /* fill it ... */   struct filler {     filler() { result<Tag>::ptr = p; }   };   static filler filler_obj; };  template<typename Tag, typename Tag::type p> typename rob<Tag, p>::filler rob<Tag, p>::filler_obj; 

Some class with private members

struct A { private:   void f() {     std::cout << "proof!" << std::endl;   } }; 

And how to access them

struct Af { typedef void(A::*type)(); }; template class rob<Af, &A::f>;  int main() {   A a;   (a.*result<Af>::ptr)(); }