Modern C++ idoms and recipes

Note that the implementation you had to refactor does not delete the elements in the vector properly. By using any you don't have to worry no new and delete is needed.

#include <any>
#include <vector>
#include <string>
#include <iostream>
using element = std::any;
using namespace std::string_literals;
int main()
{
    std::vector<element> vec_of_any;
    vec_of_any.emplace_back(1);
    vec_of_any.emplace_back(2.0);
    vec_of_any.emplace_back(std::vector<int>(2, 5));
    vec_of_any.emplace_back("Hello"s);
    for (const auto& elem : vec_of_any)
    {
        if (elem.type() == typeid(int)) {
            std::cout << std::any_cast<int>(elem) << std::endl;
        }
        if (elem.type() == typeid(double)) {
            std::cout << std::any_cast<double>(elem) << std::endl;
        }
        if (elem.type() == typeid(std::vector<int>)) {
            const auto& vec = std::any_cast<const std::vector<int>&>(elem);
            std::cout << "[";
            for(auto i = 0; i < vec.size(); ++i) {
                std::cout << vec.at(i);
                if (i < (vec.size()-1)) {
                    std:: cout << ", ";
                }
            }
            std::cout << "]\n";
        }
        if (elem.type() == typeid(std::string)) {
            std::cout << std::any_cast<std::string>(elem) << std::endl;
        }
    }
}