Why do I have to access template base class members through the this pointer?

Question

If the classes below were not templates I could simply have x in the derived class. However, with the code below, I have to use this

Answer 1

The x is hidden during the inheritance. You can unhide via:

template 
class derived : public base {

public:
    using base::x;             // added "using" statement
    int f() { return x; }
};