std::unique_ptr::operator bool

 

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C Library
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std::unique_ptr

Member functions

unique_ptr::unique_ptr

unique_ptr::~unique_ptr

unique_ptr::operator=

Modifiers

unique_ptr::release

unique_ptr::reset

unique_ptr::swap

Observers

unique_ptr::get

unique_ptr::get_deleter

unique_ptr::operator bool

unique_ptr::operator* unique_ptr::operator->

unique_ptr::operator[]

Non-member functions

operator== operator!= operator< operator> operator<= operator> operator>=

std::swap

std::hash

 

explicit operator bool() const;		(since C++11)

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

Parameters

(none)

Return value

true if *this owns an object, false otherwise.

Exceptions

noexcept specification:  

noexcept

  (since C++11)

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();
    if (ptr) std::cout << "after reset, ptr is: " << *ptr << '\n';
}

Output:

before reset, ptr is: 42

See also

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