Convert dynamic to static polymorphism in C++

Question

I need to convert a call to a function from dynamic polymorphism to static polymorphism but I'm not pretty sure on how this transformation must be done.

As first thing I have a class called Calculator that can have different implementations :

 template<class T>
 class Calculator {
  public:
     virtual void doSomething() = 0;
 };

 class IntCalculator : Calculator<int> {
   public:
    int data;
    void doSomething(){ ... use data .. };
 };

 class CharCalculator : Calculator<char> {
   public:
    void doSomething(){ .. };
 };

Then I have another class that receive as input a calculator and use it:

    class Matrix {
     private:
      Calculator* calc;
     public:
      void set_calculator(Calculator* calc){
        calculator = calc;
      }
    
      void run(){
       calculator->doSomething();
      }
    }

Now I want to convert this function call in such a way that use static polymorphism but it's not clear to me how can I do this transformation. In case of IntCalculator the attribute data must be loaded before passing the calculator to the Matrix.

Any suggestions?

Answer 1

template <typename T>
class Matrix {
private:
    T* calc;
public:
    void set_calculator(T* calc){ calculator = calc; }
    void run(){ calculator->doSomething(); }
};

Then you no longer need Calculator interface, and can directly use IntCalculator.