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

From cppreference.com
< cpp‎ | memory‎ | unique ptr
 
 
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~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.


[edit] 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.

[edit] 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