std::packaged_task<R(Args...)>::get_future - cppreference.com

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并发支持库

线程

thread

(C++11)

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hardware_destructive_interference_sizehardware_constructive_interference_size

(C++17)(C++17)

this_thread 命名空间

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原子类型
atomic (C++11)
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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_fetch_maxatomic_fetch_max_explicit (C++26)(C++26)
atomic_fetch_minatomic_fetch_min_explicit (C++26)(C++26)
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)

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std::packaged_task

成员函数
packaged_task::packaged_task
packaged_task::~packaged_task
packaged_task::operator=
packaged_task::valid
packaged_task::swap
获取结果
packaged_task::get_future
执行
packaged_task::operator()
packaged_task::make_ready_at_thread_exit
packaged_task::reset
非成员函数
swap(std::packaged_task)
辅助类
uses_allocator<std::packaged_task> (C++17 前)
推导指引(C++17)

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std::future<R> get_future();		(C++11 起)

返回与 *this 共享同一共享状态的 future。

对每个 packaged_task 只能调用一次 get_future。

参数

（无）

返回值

与 *this 共享同一共享状态的 future。

异常

遇到下列条件时为 std::future_error。

已通过调用 get_future 取得共享状态。设置错误类别为 future_already_retrieved。
*this 无共享状态。设置错误类别为 no_state。