std::unique_ptr<T,Deleter>::operator bool
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std::unique_ptr
unique_ptr::operator bool
(C++14)(C++20)
(until C++20)(C++20)
(C++20)
explicit operator bool() const noexcept;
(since C++11) (constexpr since C++23)
Checks whether *this owns an object, i.e. whether get() != nullptr.
Contents
[edit] Parameters
(none)
[edit] Return value
true if *this owns an object, false otherwise.
[edit] Example
Run this code
#include <iostream> #include <memory> int main() { std::unique_ptr <int> ptr(new int(42)); if (ptr) std::cout << "before reset, ptr is: " << *ptr << '\n'; ptr.reset(); (ptr ? (std::cout << "after reset, ptr is: " << *ptr) : (std::cout << "after reset ptr is empty")) << '\n'; }
Output:
before reset, ptr is: 42 after reset ptr is empty