What is the elegant way to `Using` polymorphic functions from base classes in c++?


This Content is from Stack Overflow. Question asked by Voile

This code compiles.

#include <bits/stdc++.h>
using namespace std;

class PA {};

class PB {};

class A {
  void foo(PA) { cout << "A PA" << endl; }
  void foo(PB) { cout << "A PB" << endl; }

class B : public A {
  // void foo(PA) { cout << "B PA" << endl; }

int main() {
  B b;
  PB PB;
  return 0;

Uncomment line 16 and the compilation will fail.

foo.cpp: In function ‘int main()’:
foo.cpp:22:9: error: cannot convert ‘PB’ to ‘PA’
   22 |   b.foo(PB);
      |         ^~
      |         |
      |         PB
foo.cpp:16:12: note:   initializing argument 1 of ‘void B::foo(PA)’
   16 |   void foo(PA) { cout << "B PA" << endl; }

This problem can be solved by using A::foo;. But I ran into a situation where there are multiple polymorphic functions in the base class. using for each of them seems silly.

Is there a way to import all functions of the base class like using A::*;? Or should this not happen at all and I should re-architecture the code?



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