【test.cpp】
#include <coroutine>
#include <iostream>
struct return_object {
struct promise_type {
return_object get_return_object() {
return_object obj;
obj.that = this;
return obj;
}
std::suspend_never initial_suspend() {
std::suspend_never never;
return never;
}
std::suspend_never final_suspend() noexcept {
std::suspend_never never;
return never;
}
void unhandled_exception() {
}
};
promise_type *that;
};
return_object counter() {
std::cout << "counter begin" << std::endl;
for (int i = 0; i < 10; i++) {
std::suspend_always a;
co_await a;
std::cout << "counter: " << i << std::endl;
}
}
int main()
{
return_object r = counter();
std::coroutine_handle<return_object::promise_type> h = std::coroutine_handle<return_object::promise_type>::from_promise(*r.that);
for (int i = 0; i < 3; i++) {
std::cout << "in main function" << std::endl;
h();
}
h.destroy();
return 0;
}
【编译命令】
g++ test.cpp -o test -fcoroutines
【程序运行结果】
