std::unique_ptr::release

 

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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

operator== operator!= operator< operator> operator<= operator> operator>=

std::swap

std::hash

 

pointer release();		(since C++11)

Releases the ownership of the managed object if any. get() returns nullptr after the call.

Parameters

(none)

Return value

Pointer to the managed object or nullptr if there was no managed object, i.e. the value which would be returned by get() before the call.

Exceptions

noexcept specification:  

noexcept

  (since C++11)

Example

run this code

#include <memory>
#include <iostream>
 
struct Foo {
    Foo() { std::cout << "Foo\n"; }
    ~Foo() { std::cout << "~Foo\n"; }
};
 
int main()
{
    std::cout << "Creating new Foo...\n";
    std::unique_ptr<Foo> up(new Foo());
 
    std::cout << "About to release Foo...\n";
    Foo* fp = up.release();
 
    if (up.get() == nullptr)
        std::cout << "Foo is no longer owned by unique_ptr...\n";
 
    delete fp;
}

Output:

Creating new Foo...
Foo
About to release Foo...
Foo is no longer owned by unique_ptr...
~Foo

See also

get	returns a pointer to the managed object (public member function)
reset	replaces the managed object (public member function)