Can a class member function template be virtual?

Question

I have heard that C++ class member function templates can\'t be virtual. Is this true?

If they can be virtual, what is an example of a scenario in which one would

Answer 1

No they can't. But:

template
class Foo {
public:
  template
  void f(const P& p) {
    ((T*)this)->f
(p);
  }
};

class Bar : public Foo {
public:
  template
  void f(const P& p) {
    std::cout << p << std::endl;
  }
};

int main() {
  Bar bar;

  Bar *pbar = &bar;
  pbar -> f(1);

  Foo *pfoo = &bar;
  pfoo -> f(1);
};

has much the same effect if all you want to do is have a common interface and defer implementation to subclasses.