Function main

example/while.cpp:17–45

int main() {
    // while_ with a Constant condition (loop is unrolled at compile-time)
    {
        std::vector<int> ints;
        auto final_state = hana::while_(hana::less.than(10_c), 0_c, [&](auto i) {
            ints.push_back(i);
            return i + 1_c;
        });

        // The state is known at compile-time
        BOOST_HANA_CONSTANT_CHECK(final_state == 10_c);

        BOOST_HANA_RUNTIME_CHECK(ints == std::vector<int>{0, 1, 2, 3, 4, 5, 6, 7, 8, 9});
    }

    // while_ with a constexpr or runtime condition (loop is not unrolled)
    {
        std::vector<int> ints;
        int final_state = hana::while_(hana::less.than(10), 0, [&](int i) {
            ints.push_back(i);
            return i + 1;
        });

        // The state is known only at runtime, or at compile-time if constexpr
        BOOST_HANA_RUNTIME_CHECK(final_state == 10);

        BOOST_HANA_RUNTIME_CHECK(ints == std::vector<int>{0, 1, 2, 3, 4, 5, 6, 7, 8, 9});
    }
}