std::unique_ptr<T,Deleter>::~unique_ptr
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std::unique_ptr
unique_ptr::~unique_ptr
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~unique_ptr();
(since C++11) (constexpr since C++23)
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.
Run this code
#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