std::unique_ptr<T,Deleter>::~unique_ptr

 

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std::unique_ptr

成員函式

unique_ptr::unique_ptr

unique_ptr::~unique_ptr

unique_ptr::operator=

修改器

unique_ptr::release

unique_ptr::reset

unique_ptr::swap

觀察器

unique_ptr::get

unique_ptr::get_deleter

unique_ptr::operator bool

unique_ptr::operator*unique_ptr::operator->

unique_ptr::operator[]

非成員函式

make_uniquemake_unique_for_overwrite (C++14)(C++20)

operator==operator!=operator<operator>operator<=operator>=operator<=> (直至 C++20)(C++20)

operator<< (C++20)

swap(std::unique_ptr)

輔助類

hash<std::unique_ptr>

 

~unique_ptr();		(C++11 起) (C++23 起為 constexpr)

若 get() == nullptr 則無效果。否則，透過 get_deleter()(get()) 銷燬所擁有的物件。

要求 get_deleter()(get()) 不丟擲異常。

注意

儘管帶有預設刪除器 的 std::unique_ptr<T> 可以用不完整型別 T 構造，但在呼叫解構函式的程式碼點，型別 T 必須是完整型別。

示例

以下程式演示了自定義刪除器的用法。

執行此程式碼

#include <iostream>
#include <memory>
 
int main () 
{
    auto deleter = [](int* ptr)
    {
        std::cout << "[deleter called]\n";
        delete ptr;
    };
 
    std::unique_ptr<int, decltype(deleter)> uniq(new int, deleter);
    std::cout << (uniq ? "not empty\n" : "empty\n");
    uniq.reset();
    std::cout << (uniq ? "not empty\n" : "empty\n");
}

輸出

not empty
[deleter called]
empty