operators (std::unique_ptr)

template<class T1, class D1, class T2, class D2> bool operator==(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y);	(1)	(since C++11)
template<class T1, class D1, class T2, class D2> bool operator!=(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y);	(2)	(since C++11)
template<class T1, class D1, class T2, class D2> bool operator<(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y);	(3)	(since C++11)
template<class T1, class D1, class T2, class D2> bool operator<=(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y);	(4)	(since C++11)
template<class T1, class D1, class T2, class D2> bool operator>(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y);	(5)	(since C++11)
template<class T1, class D1, class T2, class D2> bool operator>=(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y);	(6)	(since C++11)
template <class T, class D> bool operator==(const unique_ptr<T, D>& x, nullptr_t) noexcept;	(7)	(since C++11)
template <class T, class D> bool operator==(nullptr_t, const unique_ptr<T, D>& x) noexcept;	(8)	(since C++11)
template <class T, class D> bool operator!=(const unique_ptr<T, D>& x, nullptr_t) noexcept;	(9)	(since C++11)
template <class T, class D> bool operator!=(nullptr_t, const unique_ptr<T, D>& x) noexcept;	(10)	(since C++11)
template <class T, class D> bool operator<(const unique_ptr<T, D>& x, nullptr_t);	(11)	(since C++11)
template <class T, class D> bool operator<(nullptr_t, const unique_ptr<T, D>& y);	(12)	(since C++11)
template <class T, class D> bool operator<=(const unique_ptr<T, D>& x, nullptr_t);	(13)	(since C++11)
template <class T, class D> bool operator<=(nullptr_t, const unique_ptr<T, D>& y);	(14)	(since C++11)
template <class T, class D> bool operator>(const unique_ptr<T, D>& x, nullptr_t);	(15)	(since C++11)
template <class T, class D> bool operator>(nullptr_t, const unique_ptr<T, D>& y);	(16)	(since C++11)
template <class T, class D> bool operator>=(const unique_ptr<T, D>& x, nullptr_t);	(17)	(since C++11)
template <class T, class D> bool operator>=(nullptr_t, const unique_ptr<T, D>& y);	(18)	(since C++11)

Compares the pointer values of two unique_ptrs, or a unique_ptr and nullptr.

1-6) Compares two unique_ptrs

7-18) Compares a unique_ptr and nullptr.

Parameters

x, y - unique_ptrs to compare

Return value

1) x.get() == y.get().

2) x.get() != y.get().

3) std::less<CT>()(x.get(), y.get()), where CT is std::common_type<unique_ptr<T1, D1>::pointer, unique_ptr<T2, D2>::pointer>::type.

4) !(y < x).

5) y < x.

6) !(x < y).

7-8) !x.

9-10) (bool)x.

11) std::less<unique_ptr<T,D>::pointer>()(x.get(), nullptr).

12) std::less<unique_ptr<T,D>::pointer>()(nullptr, y.get()).

13) nullptr < x.

14) y < nullptr.

15) !(nullptr < x).

16) !(y < nullptr).

17) !(x < nullptr).

18) !(nullptr < y).

Example

#include <iostream>
#include <memory>
 
int main() 
{
    std::unique_ptr<int> p1(new int(42));
    std::unique_ptr<int> p2(new int(42));
 
    std::cout << "p1 == p1: " << (p1 == p1) << '\n';
 
    // p1 and p2 point to different memory locations, so p1 != p2
    std::cout << "p1 == p2: " << (p1 == p2) << '\n';
}

Output:

p1 == p1: 1
p1 == p2: 0

operators (std::unique_ptr)

Parameters

Return value

Example

See also