operator==,!=(std::allocator)

Allocators
allocator
allocator_traits (C++11)
allocation_result (C++23)
allocator_arg (C++11)
uses_allocator (C++11)
uses_allocator_construction_args (C++20)
make_obj_using_allocator (C++20)
uninitialized_construct_using_allocator (C++20)
scoped_allocator_adaptor (C++11)
pmr::polymorphic_allocator (C++17)
Memory resources
pmr::memory_resource (C++17)
pmr::get_default_resource (C++17)
pmr::set_default_resource (C++17)
pmr::new_delete_resource (C++17)
pmr::null_memory_resource (C++17)
pmr::synchronized_pool_resource (C++17)
pmr::unsynchronized_pool_resource (C++17)
pmr::monotonic_buffer_resource (C++17)
pmr::pool_options (C++17)
Garbage collection support
declare_reachable (C++11)(until C++23)
undeclare_reachable (C++11)(until C++23)
declare_no_pointers (C++11)(until C++23)
undeclare_no_pointers (C++11)(until C++23)
pointer_safety (C++11)(until C++23)
get_pointer_safety (C++11)(until C++23)
Uninitialized storage
raw_storage_iterator (until C++20*)
get_temporary_buffer (until C++20*)
return_temporary_buffer (until C++20*)
Explicit lifetime management
start_lifetime_asstart_lifetime_as_array (C++23)(C++23)

std::allocator

Member functions
allocator::allocator
allocator::~allocator
allocator::address (until C++20)
allocator::allocate
allocator::allocate_at_least (C++23)
allocator::deallocate
allocator::max_size (until C++20)
allocator::construct (until C++20)
allocator::destroy (until C++20)
Non-member functions
operator==operator!= (until C++20)

	(1)
template < class T1, class T2 > bool operator== ( const allocator<T1> & lhs, const allocator<T2> & rhs ) throw ( ) ;			(until C++11)
template < class T1, class T2 > bool operator== ( const allocator<T1> & lhs, const allocator<T2> & rhs ) noexcept ;			(since C++11) (until C++20)
template < class T1, class T2 > constexpr bool operator== ( const allocator<T1> & lhs, const allocator<T2> & rhs ) noexcept ;			(since C++20)
		(2)
template < class T1, class T2 > bool operator! = ( const allocator<T1> & lhs, const allocator<T2> & rhs ) throw ( ) ;				(until C++11)
template < class T1, class T2 > bool operator! = ( const allocator<T1> & lhs, const allocator<T2> & rhs ) noexcept ;				(since C++11) (until C++20)

Compares two default allocators. Since default allocators are stateless, two default allocators are always equal.

1) Returns true.

2) Returns false.

The != operator is synthesized from operator==.

(since C++20)

lhs, rhs

-

default allocators to compare

1) true

2) false

Compiler support
Freestanding and hosted
Language
Standard library
Standard library headers
Named requirements
Feature test macros (C++20)
Language support library
Concepts library (C++20)
Diagnostics library
Memory management library
Metaprogramming library (C++11)
General utilities library
Containers library
Iterators library
Ranges library (C++20)
Algorithms library
Strings library
Text processing library
Numerics library
Date and time library
Input/output library
Filesystem library (C++17)
Concurrency support library (C++11)
Execution support library (C++26)
Technical specifications
Symbols index
External libraries