std::pmr::operator==, std::pmr::operator!=

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Defined in header <memory_resource>
template< class T1, class T2 >

bool operator==( const std::pmr::polymorphic_allocator<T1>& lhs,

                 const std::pmr::polymorphic_allocator<T2>& rhs ) noexcept;
(1) (since C++17)
friend bool operator==( const polymorphic_allocator& lhs,
                        const polymorphic_allocator& rhs ) noexcept;
(2) (since C++17)
template< class T1, class T2 >

bool operator!=( const std::pmr::polymorphic_allocator<T1>& lhs,

                 const std::pmr::polymorphic_allocator<T2>& rhs ) noexcept;
(3) (since C++17)
(until C++20)
friend bool operator!=( const polymorphic_allocator& lhs,
                        const polymorphic_allocator& rhs ) noexcept;
(4) (since C++17)
(until C++20)

Compares two polymorphic allocators. Two polymorphic allocators compare equal if their underlying memory resource compares equal.

1) Returns *lhs.resource() == *rhs.resource()
2) Same as (1), allowing conversion to polymorphic_allocator.
This function is not visible to ordinary unqualified or qualified lookup, and can only be found by argument-dependent lookup when std::pmr::polymorphic_allocator is an associated class of the arguments.
3) Returns !(lhs == rhs)
4) Same as (3), allowing conversion to polymorphic_allocator.
This function is not visible to ordinary unqualified or qualified lookup, and can only be found by argument-dependent lookup when std::pmr::polymorphic_allocator is an associated class of the arguments.

The != operator is synthesized from operator==.

(since C++20)

Parameters

lhs, rhs - polymorphic allocators to compare

Return value

1-2) *lhs.resource() == *rhs.resource()
3-4) !(lhs == rhs)

Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR Applied to Behavior as published Correct behavior
LWG 3683 C++17 polymorphic_allocator could not be compared with types convertible to it overload added