#include <iostream>
#include <experimental/coroutine>

struct suspend_never {
	bool await_ready() noexcept {
		return true;
	}

	void await_suspend(std::experimental::coroutine_handle<>) noexcept {}
	void await_resume() noexcept {}
};

struct suspend_always {
	bool await_ready() noexcept {
		return false;
	}

	void await_suspend(std::experimental::coroutine_handle<>) noexcept {}
	void await_resume() noexcept {}
};