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

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Utilities library
General utilities
Relational operators (deprecated in C++20)
Dynamic memory management
Uninitialized memory algorithms
Constrained uninitialized memory algorithms
Allocators
Garbage collection support
(C++11) (until C++23)
(C++11) (until C++23)
(C++11) (until C++23)
(C++11) (until C++23)
(C++11) (until C++23)
(C++11) (until C++23)



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

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