如何創建一個空的 std::tuple？

Question

我需要構造一個std::tuple對象，以便std::tuple_size<T>::value = 0。有沒有辦法做到這一點？

Answer 1

std::tuple<> empty;
using empty_t = std::tuple<>;
auto empty2 = std::make_tuple();
static_assert(std::tuple_size<std::tuple<>>::value == 0);