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

 

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std::unique_ptr

成员函数

unique_ptr::unique_ptr

unique_ptr::~unique_ptr

unique_ptr::operator=

修饰符

unique_ptr::release

unique_ptr::reset

unique_ptr::swap

观察者

unique_ptr::get

unique_ptr::get_deleter

unique_ptr::operator bool

unique_ptr::operator*unique_ptr::operator->

unique_ptr::operator[]

非成员函数

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

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

operator<< (C++20)

swap(std::unique_ptr)

辅助类

hash<std::unique_ptr>

 

Deleter& get_deleter() noexcept;		(自 C++11 起) (自 C++23 起为 constexpr)
const Deleter& get_deleter() const noexcept;		(自 C++11 起) (自 C++23 起为 constexpr)

返回将用于销毁托管对象的删除器对象。

参数

(无)

返回值

存储的删除器对象。

示例

运行此代码

#include <iostream>
#include <memory>
 
struct Foo
{
    Foo() { std::cout << "Foo() 0x" << std::hex << (void*)this << '\n'; }
    ~Foo() { std::cout << "~Foo() 0x" << std::hex << (void*)this << '\n'; }
};
 
struct D
{
    int number;
 
    void bar()
    {
        std::cout << "call D::bar(), my number is: " << std::dec << number << '\n';
    }
 
    void operator()(Foo* p) const
    {
        std::cout << "call deleter for Foo object 0x" << std::hex << (void*)p << '\n';
        delete p;
    }
};
 
int main()
{
    std::cout << "main start\n";
 
    std::unique_ptr<Foo, D> up1(new Foo(), D(42));
    D& del1 = up1.get_deleter();
    del1.bar();
 
    std::unique_ptr<Foo, D> up2(new Foo(), D(43));
    D& del2 = up2.get_deleter();
    auto* released = up2.release();
    del2(released);
 
    std::cout << "main end\n";
}

输出

main start
Foo() 0x0x90cc30
call D::bar(), my number is: 42
Foo() 0x0x90cc50
call deleter for Foo object 0x0x90cc50
~Foo() 0x0x90cc50
main end
call deleter for Foo object 0x0x90cc30
~Foo() 0x0x90cc30

另请参见

get_deleter

如果拥有，则返回指定类型的删除器 (函数模板)