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std::unique_ptr::operator bool

性病：：独特[医]PTR：：操作员bool

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

检查是否*this拥有一个对象，即get() != nullptr...

参数

%280%29

返回值

true如果*this拥有一件物品，false否则。

例外

noexcept规格：

noexcept

例

二次

#include <iostream>
#include <memory>
 
int main()
{
    std::unique_ptr<int> ptr(new int(42)
 
    if (ptr) std::cout << "before reset, ptr is: " << *ptr << '\n';
    ptr.reset(
    if (ptr) std::cout << "after reset, ptr is: " << *ptr << '\n';
}

二次

产出：

二次

before reset, ptr is: 42

二次

另见

getreturns a pointer to the managed object (public member function)

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http：//en.cppreference.com/w/cpp/Memory/UNIQUE[医]PTR/算子[医]布尔

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