std::unique_ptr::~unique_ptr

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< cpplrm; | memorylrm; | unique ptr
Dynamic memory management
Uninitialized storage
(C++17)
Garbage collection support
Miscellaneous
(C++20)
(C++11)
(C++11)
C Library
Low level memory management
~unique_ptr();
(since C++11)

If get() == nullptr there are no effects. Otherwise, the owned object is destroyed via get_deleter()(get()).

Requires that get_deleter()(get()) does not throw exceptions.


Notes

Although std::unique_ptr<T> with the default deleter may be constructed with incomplete type T, the type T must be complete at the point of code where the destructor is called.

Example

The following program demonstrates usage of a custom deleter.

#include <iostream>
#include <memory>

int main () 
{
    auto deleter = [](int* ptr){
        std::cout << "[deleter called]\n";
        delete ptr;
    };

    std::unique_ptr<int,decltype(deleter)> uniq(new int, deleter);
    std::cout << (uniq ? "not empty\n" : "empty\n");
    uniq.reset();
    std::cout << (uniq ? "not empty\n" : "empty\n");
}

Output:

not empty
[deleter called]
empty