Creating several mutually incompatible numerical types [duplicate]

Answer 1

Just to consider:

#include 

template 
class base{
  public:
    T val;

    base(T val_arg) : val (val_arg) {}

    base& operator+(const base& a)
    {
      val += a.val;
      return *this;
    }
};

template 
std::ostream& operator<< (std::ostream& s, const base& a)
{
    s << a.val;
    return s;
}

typedef base my_type_1;
typedef base my_type_2;

int main()
{
   my_type_1 v1(1);
   my_type_1 v2(2);
   my_type_1 res = v1 + v2;
   std::cout << res << std::endl;

   my_type_1 r1 = v1;

   my_type_2 v3(3);
   //my_type_1 r2 = v3; // This is a compilation error
   //my_type_1 res2 = v1 + v3; // This is a compilation error
   //std::cout << res2 << std::endl;
   return 0;
}