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

 

C++

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std::unique_ptr

Member functions

unique_ptr::unique_ptr

unique_ptr::~unique_ptr

unique_ptr::operator=

Modifiers

unique_ptr::release

unique_ptr::reset

unique_ptr::swap

Observers

unique_ptr::get

unique_ptr::get_deleter

unique_ptr::operator bool

unique_ptr::operator*unique_ptr::operator->

unique_ptr::operator[]

Non-member functions

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

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

operator<< (C++20)

swap(std::unique_ptr)

Helper classes

hash<std::unique_ptr>

 

Deleter& get_deleter() noexcept;		(since C++11) (constexpr since C++23)
const Deleter& get_deleter() const noexcept;		(since C++11) (constexpr since C++23)

Returns the deleter object which would be used for destruction of the managed object.

Parameters

(none)

Return value

The stored deleter object.

Example

Run this code

#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";
}

Output:

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

See also

get_deleter

returns the deleter of specified type, if owned (function template)