std::unique_ptr<T,Deleter>>::operator bool

Since C++11

explicit operator bool() const noexcept;

Since C++23

constexpr explicit operator bool() const noexcept;

Checks whether *this owns an object, i.e. whether get() != nullptr.

Parameters

(none)

Return value

true if *this owns an object, false otherwise.

Example

#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';
}

Result

before reset, ptr is: 42
after reset ptr is empty