c++ - Template function inside template class

Question

I have this code:

template <class T>
class MyClass {
    public:
        template <class U>
        void foo() {
            U a;
            a.invoke();
        }
};

I want it in this form:

template <class T>
class MyClass {
    public:
        template <class U>
        void foo();
};

template <class T> /* ????? */
void MyClass<T>::foo() {
    U a;
    a.invoke();
}

How I can to do this? What is the right syntax?

Answer 1

Write this:

template <class T>
template <class U>
void MyClass<T>::foo() { /* ... */ }