std::chrono:: choose

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定义于头文件 `<chrono>`
enum class choose { earliest, latest } ;		(C++20 起)

作用域枚举类型 choose 可传递给 std::chrono::time_zone 和 std::chrono::zoned_time 的特定成员函数，用于控制如何解析不明确或不存在的本地时间。传递 choose::earliest 将返回较早的时间点，而传递 choose::latest 将返回较晚的时间点。（对于不存在的本地时间，这两个时间点是相同的。）

如果未传递 choose 且遇到不明确或不存在的时间，将抛出相应的 std::chrono::ambiguous_local_time 或 std::chrono::nonexistent_local_time 异常。

另请参阅

(constructor)	构造 `zoned_time` 对象 ( `std::chrono::zoned_time<Duration,TimeZonePtr>` 的公开成员函数)
to_sys	将此时区中的 local_time 转换为 sys_time ( `std::chrono::time_zone` 的公开成员函数)

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std::chrono:: choose

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