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std::latch:: try_wait

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std::latch
bool try_wait ( ) const noexcept ;
(C++20 起)

仅当内部计数器归零时返回 true 。即使内部计数器已归零，该函数仍可能以极低概率伪返回 false 。

参数

(无)

返回值

以极低概率返回 false ，否则 cnt == 0 ，其中 cnt 表示内部计数器的值。

注释

允许出现伪结果的原因是为了允许实现使用比 std::memory_order_seq_cst 更宽松的内存序。