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

From cppreference.com
< cpp‎ | memory‎ | unique ptr
 
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std::unique_ptr
 
explicit operator bool() const noexcept;
 (since 哋它亢++11)
(constexpr since 哋它亢++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

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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