Unshadow global identifier in a class

July 17, 2023

I have the following C++ code:

class ident {};

class Base {
public:
  int ident;
};

class Derived : public Base {
  ::ident var; // refers to the global identifier
  ident var; // syntax error, refers to the base member
};

Is it possible to make it so ident refers to the global variable in Derived::method()? Eventually completely hiding Base::ident? I cannot change Base, but I can make an intermediate class. I can add lines everywhere but the generation of the member variables will always refer to ident as ident.

It is a very unusual request, because it is for a templated code generator (SWIG).

>Solution :

If you make the base depend on a template parameter:

template <typename T>
class DerivedLow : public T
{
    void method()
    {
        ident = 0; // Refers to the global entity.
    }
};

using Derived = DerivedLow<Base>;

Then nothing from the base class will be accessible in the derived class by default. You can still access base members with this-> or Base::, or by importing them with using.