xtensor_3_N_4.hpp

template <class T, std::size_t I>
struct nested_initializer_list
{
    using nested_type =
        typename nested_initializer_list<T, I - 1>::type;
    using type = std::initializer_list<nested_type>;
};

template <class T>
struct nested_initializer_list<T, 0>
{
    using type = T;
};

template <class T, std::size_t I>
using nested_initializer_list_t =
    typename nested_initializer_list<T, I>::type;