Using variadic template as parameter for both class and method

My question is about the following piece of code: ``` template <class...T> class A { public: template <class...S> static void a() { } }; template <class...T> class B { public: template <class...S> void b() { A<T...>::a<S...>(); } }; int main(int argc, char** argv) { return 0; } ``` I have a class `A` that has a variadic template and contains a static method `a` that has another variadic template. From somewhere else (class `B` in this case) I have two different sets of variadic templates I want to pass to `A::a`. The compiler (GCC 4.8.1) gives the following error message: ``` main.cpp: In static member function ‘static void B<T>::b()’: main.cpp:16:22: error: expected primary-expression before ‘...’ token A <T...>::a<S...>(); ^ main.cpp:16:22: error: expected ‘;’ before ‘...’ token ``` Also notice that when I change the method `b()` to this: ``` void b() { A<int, char, short>::a<S...>(); } ``` or some other specification of A's templates then the code compiles just fine. What is wrong with the above code?