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

Replaces the managed object.

Parameters

Notes

To replace the managed object while supplying a new deleter as well, move assignment operator may be used.

A test for self-reset, i.e. whether ptr points to an object already managed by * this , is not performed, except where provided as a compiler extension or as a debugging assert. Note that code such as p. reset ( p. release ( ) ) does not involve self-reset, only code like p. reset ( p. get ( ) ) does.

Example

#include <iostream>
#include <memory>
 
struct Foo // object to manage
{
    Foo() { std::cout << "Foo...\n"; }
    ~Foo() { std::cout << "~Foo...\n"; }
};
 
struct D // deleter
{
    void operator() (Foo* p)
    {
        std::cout << "Calling delete for Foo object... \n";
        delete p;
    }
};
 
int main()
{
    std::cout << "Creating new Foo...\n";
    std::unique_ptr<Foo, D> up(new Foo(), D()); // up owns the Foo pointer (deleter D)
 
    std::cout << "Replace owned Foo with a new Foo...\n";
    up.reset(new Foo());  // calls deleter for the old one
 
    std::cout << "Release and delete the owned Foo...\n";
    up.reset(nullptr);      
}

Creating new Foo...
Foo...
Replace owned Foo with a new Foo...
Foo...
Calling delete for Foo object...
~Foo...
Release and delete the owned Foo...
Calling delete for Foo object...
~Foo...

Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

See also