Question

If we have the following simple code in C#:

class Program
{
     static void Main(string[] args)
     {
          string x = "Hello World";
          test(x);
          int y = 101;
          test(y);
          Console.ReadKey();
      }

      static void test(object val)
      {
          Console.WriteLine(val);
      }
}  

So, we have a reference type object as parameter – works fine. How to do a similar thing in C++?

OT: Without direct typing we can use var keyword, in C++ exists keyword auto. Is here any similar reference type like object or some way/tricks to prove it?

Answer 1

In C++, not all objects derive from a common base type; there is no universal run-time polymorphism. You might get the behavior you need, however, by using compile-time polymorphism via templates.

#include <iostream>
#include <string>

template <class T> void test(const T& val)
{
    std::cout << val << "\n";
}


int main(int ac, char **av)
{
    std::string x = "Hello World";
    test(x);
    int y = 101;
    test(y);
}