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

 

C++

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 control library (C++26)

Technical specifications

Symbols index

External libraries

 

Memory management library

Allocators allocator allocator_traits (C++11) allocation_result (C++23) scoped_allocator_adaptor (C++11) allocator_arg (C++11) uses_allocator (C++11) uses_allocator_construction_args (C++20) make_obj_using_allocator (C++20) pmr::polymorphic_allocator (C++17) uninitialized_construct_using_allocator (C++20) 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::pool_options (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) Explicit lifetime management start_lifetime_as (C++23) start_lifetime_as_array (C++23) Types for composite class design indirect (C++26) polymorphic (C++26) Miscellaneous pointer_traits (C++11) to_address (C++20) addressof (C++11) align (C++11) assume_aligned (C++20) is_sufficiently_aligned (C++26) C Library malloc      free calloc realloc aligned_alloc (C++17) free_sized (C++26) free_aligned_sized (C++26) memalignment (C++26) Uninitialized storage (until C++20*) raw_storage_iterator get_temporary_buffer return_temporary_buffer Garbage collector support (until C++23) declare_reachable (C++11) declare_no_pointers (C++11) pointer_safety (C++11) undeclare_reachable (C++11) undeclare_no_pointers (C++11) get_pointer_safety (C++11)

Specialized <memory> algorithms Low level memory management operator newoperator new[] operator deleteoperator delete[] nothrow nothrow_t new_handler set_new_handler get_new_handler (C++11) bad_alloc bad_array_new_length (C++11) align_val_t (C++17) destroying_delete_t (C++20) launder (C++17) Smart pointers unique_ptr (C++11) shared_ptr (C++11) weak_ptr (C++11) auto_ptr (until C++17*) owner_less (C++11) owner_less<void> (C++17) owner_hash (C++26) owner_equal (C++26) enable_shared_from_this (C++11) bad_weak_ptr (C++11) default_delete (C++11) out_ptr_t (C++23) inout_ptr_t (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)

 

template< class T1, class T2 > bool operator==( const allocator<T1>& lhs, const allocator<T2>& rhs ) throw();	(1)	(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)
template< class T1, class T2 > bool operator!=( const allocator<T1>& lhs, const allocator<T2>& rhs ) throw();	(2)	(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)

See More

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)

Parameters

lhs, rhs

-

default allocators to compare

Return value

1) true

2) false