tuple to pair

#include <utility>

// C++14
template <int i1, int i2, typename... Args>
auto to_pair(std::tuple<Args...> t)
{
    return std::make_pair(std::get<i1>(t), std::get<i2>(t));
}

// C++11
template <int i1, int i2, typename... Args>
auto to_pair(std::tuple<Args...> t) 
        -> decltype(std::make_pair(std::get<i1>(t),std::get<i2>(t)))
{
    return std::make_pair(std::get<i1>(t), std::get<i2>(t));
}