std::experimental:: in_place_t
From cppreference.net
<
cpp
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experimental
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optional
C++
Experimental
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std::experimental::optional
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in_place_t
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定义于头文件
<experimental/optional>
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||
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struct
in_place_t
{
}
;
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(库基础技术规范) | |
std::experimental::in_place_t
是一个空类类型，用于消除构造函数和成员函数重载的歧义，这些函数接受参数（可能为参数包）以进行某些值的原位构造。
参见
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原位构造标签
(标签) |
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(C++17)
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可能持有或未持有对象的包装器
(类模板) |