#include <cstdlib>
#include <utility>
#include <iostream>

struct Obj
{
  size_t v;
};

template <size_t I>
static Obj foo() { return Obj{I}; }

template <class T, size_t... I>
static T switch_(size_t i, std::index_sequence<I...>)
{
  T ret;
  const bool ar[] = {
    ((i == I) ? (ret = foo<I>(),false):false, false)... };
  return ret;
}

template <class T, size_t Max>
static T do_switch(size_t i)
{
  return switch_<T>(i, std::make_index_sequence<Max>());
}

int main(int argc, char** argv)
{
  auto ret = do_switch<Obj, 10>(argc);
  std::cout << ret.v << std::endl;
  return 0;
}