N variadic tuple

world.cpp

#include <iostream>
#include <string>
#include <type_traits>

class Frombler {
  public:
  virtual void fromble() = 0;
};

class Foo : public Frombler {
  public:
  void fromble() {
    std::cout << "Foo Foo" << std::endl;
  }
};

class Bar : public Frombler {
  public:
    explicit Bar(const std::string& t)
      : text(t)
    {
    }
    void fromble() {
      std::cout << "Bar " << text << std::endl;
    }
  private:
  std::string text;
};

template <typename T>
class Generator {
  public:
  Generator() {
    static_assert(std::is_base_of<Frombler, T>::value, "T is not derived from Frombler");
  }
};

template <typename T, class... Mixins>
class ConcreteGenerator: public Generator<T> {
  public:
  ConcreteGenerator() 
  : Generator<T>() {
  }

  T makeMember(const Mixins&... mixins) {
    return T(mixins...);
  }
};

int main() {
  auto foo = ConcreteGenerator<Foo>();
  auto bar = ConcreteGenerator<Bar, std::string>();
  Foo f1 = foo.makeMember();
  f1.fromble();
  Bar b1 = bar.makeMember("lolz");
  b1.fromble();
}