std::swap(std::promise)

 

C++

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功能特性测试宏 (C++20)

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并发支持库

线程 thread (C++11) jthread (C++20) stop_token (C++20) stop_source (C++20) stop_callback (C++20) hardware_destructive_interference_sizehardware_constructive_interference_size (C++17)(C++17) this_thread 命名空间 get_id (C++11) yield (C++11) sleep_for (C++11) sleep_until (C++11) 原子类型 atomic (C++11) atomic_ref (C++20) atomic_flag (C++11) 原子类型的初始化 atomic_init (C++11)(C++20 中弃用) ATOMIC_VAR_INIT (C++11)(C++20 中弃用) ATOMIC_FLAG_INIT (C++11) 原子操作的自由函数 atomic_storeatomic_store_explicit (C++11)(C++11) atomic_loadatomic_load_explicit (C++11)(C++11) atomic_exchangeatomic_exchange_explicit (C++11)(C++11) atomic_compare_exchange_weakatomic_compare_exchange_weak_explicitatomic_compare_exchange_strongatomic_compare_exchange_strong_explicit (C++11)(C++11)(C++11)(C++11) atomic_fetch_addatomic_fetch_add_explicit (C++11)(C++11) atomic_fetch_subatomic_fetch_sub_explicit (C++11)(C++11) atomic_fetch_andatomic_fetch_and_explicit (C++11)(C++11) atomic_fetch_oratomic_fetch_or_explicit (C++11)(C++11) atomic_fetch_xoratomic_fetch_xor_explicit (C++11)(C++11) atomic_is_lock_free (C++11) atomic_waitatomic_wait_explicit (C++20)(C++20) atomic_notify_one (C++20) atomic_notify_all (C++20)

原子标志的自由函数 atomic_flag_test_and_setatomic_flag_test_and_set_explicit (C++11)(C++11) atomic_flag_clearatomic_flag_clear_explicit (C++11)(C++11) atomic_flag_testatomic_flag_test_explicit (C++20)(C++20) atomic_flag_waitatomic_flag_wait_explicit (C++20)(C++20) atomic_flag_notify_one (C++20) atomic_flag_notify_all (C++20) 内存序 memory_order (C++11) kill_dependency (C++11) atomic_thread_fence (C++11) atomic_signal_fence (C++11) 互斥 mutex (C++11) recursive_mutex (C++11) shared_mutex (C++17) timed_mutex (C++11) recursive_timed_mutex (C++11) shared_timed_mutex (C++14) 通用锁管理 lock_guard (C++11) scoped_lock (C++17) unique_lock (C++11) shared_lock (C++14) defer_lock_ttry_to_lock_tadopt_lock_t (C++11)(C++11)(C++11) lock (C++11) try_lock (C++11) defer_locktry_to_lockadopt_lock (C++11)(C++11)(C++11) once_flag (C++11) call_once (C++11) 条件变量 condition_variable (C++11) condition_variable_any (C++11) notify_all_at_thread_exit (C++11) cv_status (C++11) 信号量 counting_semaphorebinary_semaphore (C++20)(C++20) 闩与屏障 latch (C++20) barrier (C++20) future promise (C++11) future (C++11) shared_future (C++11) packaged_task (C++11) async (C++11) launch (C++11) future_status (C++11) future_error (C++11) future_category (C++11) future_errc (C++11)

 

std::promise

成员函数

promise::promise

promise::~promise

promise::operator=

promise::swap

获取结果

promise::get_future

设置结果

promise::set_value

promise::set_value_at_thread_exit

promise::set_exception

promise::set_exception_at_thread_exit

 

在标头 <future> 定义
template< class R > void swap( promise<R> &lhs, promise<R> &rhs ) noexcept;		(C++11 起)

为 std::promise 特化 std::swap 算法。交换 lhs 与 rhs 的共享状态。等效地调用 lhs.swap(rhs) 。

参数

lhs, rhs

-

要交换状态的 promise

返回值

（无）

参阅

swap	交换二个 promise 对象 (公开成员函数)