Function main

example/ext/std/integer_sequence/foldable.cpp:16–25

auto add = [](auto a, auto b, auto c) { return a + b + c; };

int main() {
    std::tuple<int, long, double> tuple{1, 2l, 3.3};

    auto sum = hana::unpack(std::integer_sequence<int, 0, 1, 2>{}, [&](auto ...i) {
        // the `i`s are `std::integral_constant<int, ...>`s
        return add(std::get<decltype(i)::value>(tuple)...);
    });

    BOOST_HANA_RUNTIME_CHECK(sum == 6.3);
}