std::experimental::optional<T>:: operator bool
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cpp
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experimental
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optional
C++
Experimental
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std::experimental::optional
| Member functions | ||||
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optional::operator bool
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constexpr
explicit
operator
bool
(
)
const
noexcept
;
|
(库基础技术规范) | |
检查 * this 是否包含值。
参数
(无)
返回值
若 * this 包含值则为 true ，若 * this 不包含值则为 false 。