Function g

example/stop_token.cpp:5–22

using namespace std::chrono_literals;

task<> g(stop_token token) {
    printf("g() is running...\n");

    stop_callback guard{token, [] {
                            printf("Callback is triggerd\n");
                        }};

    co_await timeout(1s);

    // It is your responsibility to check
    // whether the task has been cancelled.
    if (token.stop_requested()) {
        printf("g() exits early\n");
        co_return;
    }

    printf("g() finished\n");
}

task<> f() {
    // The same as std::stop_source.