Varying number of definitions in a variadic template class

I recently thought of a problem. Let's say there is a variadic template like this one:

template <typename... Types>
class example
{
   //something
};

Now what I want to achieve is that when I create an object of example<int, double, float> , this template instance will be compiled:

class example<int, double, float>
{
    int int_array[5];
    double double_array[5];
    float float_array[5];
}

And when I create an object of example<char, long, myClass2, myClass3> , this instance of the class template will be generated:

class example<char, long, myClass2, myClass3>
{
    char char_array[5];
    long long_array[5];
    myClass2 myClass2_array[5];
    myClass3 myClass3_array[5];
}

So basically, for each variadic list of template parameters, repeat an action for every of the type name passed. In my example, I declared a 5-element array for each type passed to the variadic template. The names don't have to be "type_array", it can be anything, as long as I can do an action (like declaring a variable) for each of the type passed.

Is that possible?

---

那么......我想你可以使用继承

#include <string>
#include <iostream>

template <typename T>
struct wrp
 { T a[5]; };

template <typename ... Ts>
struct example : public wrp<Ts>...
 { };

int main()
 {
   example <int, float, std::string>  e0;

   e0.wrp<int>::a[0] = 1;
   e0.wrp<float>::a[0] = 1.1f;
   e0.wrp<std::string>::a[0] = "1.11";

   std::cout << e0.wrp<int>::a[0] << std::endl;         // print 1
   std::cout << e0.wrp<float>::a[0] << std::endl;       // print 1.1
   std::cout << e0.wrp<std::string>::a[0] << std::endl; // print 1.11
 }

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