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

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Compiler support
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Standard library
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Feature test macros(C++20)
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Memory management library

voidify

(exposition only*)

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allocator
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Uninitialized memory algorithms

uninitialized_copy
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uninitialized_default_construct (C++17)
uninitialized_value_construct (C++17)
destroy (C++17)
uninitialized_default_construct_n (C++17)
uninitialized_value_construct_n (C++17)
destroy_n (C++17)
destroy_at (C++17)

Constrained uninitialized memory algorithms

ranges::uninitialized_copy (C++20)
ranges::uninitialized_fill (C++20)
ranges::uninitialized_move (C++20)
ranges::uninitialized_copy_n (C++20)
ranges::uninitialized_fill_n (C++20)
ranges::uninitialized_move_n (C++20)
ranges::construct_at (C++20)

ranges::uninitialized_default_construct (C++20)
ranges::uninitialized_value_construct (C++20)
ranges::destroy (C++20)
ranges::uninitialized_default_construct_n (C++20)
ranges::uninitialized_value_construct_n (C++20)
ranges::destroy_n (C++20)
ranges::destroy_at (C++20)

Memory resources

pmr::memory_resource (C++17)
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pmr::set_default_resource (C++17)
pmr::new_delete_resource (C++17)
pmr::pool_options (C++17)

pmr::null_memory_resource (C++17)
pmr::synchronized_pool_resource (C++17)
pmr::unsynchronized_pool_resource (C++17)
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Explicit lifetime management
start_lifetime_as (C++23)
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Types for composite class design
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Low level memory
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operator newoperator new[]

operator deleteoperator delete[]

(C++11)

(C++11)

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(C++17)

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(C++11)

(C++11)

(until C++17*)

(C++11)

(C++17)

(C++26)

(C++26)

enable_shared_from_this

(C++11)

(C++11)

(C++11)

(C++23)

(C++23)

(C++11)

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(C++11)

(C++11)

(C++20)

is_sufficiently_aligned

(C++26)

C Library

malloc
calloc
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free
aligned_alloc (C++17)

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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>

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

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

[edit]Parameters

(none)

[edit]Return value

The stored deleter object.

[edit]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 startFoo() 0x0x90cc30call D::bar(), my number is: 42Foo() 0x0x90cc50call deleter for Foo object 0x0x90cc50~Foo() 0x0x90cc50main endcall deleter for Foo object 0x0x90cc30~Foo() 0x0x90cc30