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

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< cpp‎ | memory‎ | unique ptr
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std::unique_ptr
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

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

See also

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