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std::error_code::operator bool

STD：错误[医]代码：：操作员bool

explicit operator bool() const;​(since C++11)

检查错误值是否有效，即非零。

参数

%280%29

返回值

false如果value() == 0，，，true否则。

例外

noexcept规格：

noexcept

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