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

explicit operator bool() const noexcept;
(since C++11)
(constexpr since C++23)

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';
}

Output:

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

See also

get
returns a pointer to the managed object
(public member function)

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https://en.cppreference.com/cpp/memory/unique_ptr/operator_bool

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