std::pmr::polymorphic_allocator::polymorphic_allocator

 

C++

Language

Standard Library Headers

Freestanding and hosted implementations

Named requirements

Language support library

Concepts library (C++20)

Diagnostics library

Utilities library

Strings library

Containers library

Iterators library

Ranges library (C++20)

Algorithms library

Numerics library

Input/output library

Localizations library

Regular expressions library (C++11)

Atomic operations library (C++11)

Thread support library (C++11)

Filesystem library (C++17)

Technical Specifications

 

Dynamic memory management

Smart pointers unique_ptr (C++11) shared_ptr (C++11) weak_ptr (C++11) auto_ptr (until C++17) owner_less (C++11) enable_shared_from_this (C++11) bad_weak_ptr (C++11) default_delete (C++11) Allocators allocator allocator_traits (C++11) allocator_arg_t (C++11) 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)

Uninitialized storage uninitialized_copy uninitialized_fill uninitialized_move (C++17) uninitialized_default_construct (C++17) uninitialized_value_construct (C++17) destroy (C++17) uninitialized_copy_n (C++11) uninitialized_fill_n uninitialized_move_n (C++17) uninitialized_default_construct_n (C++17) uninitialized_value_construct_n (C++17) destroy_n (C++17) destroy_at (C++17) raw_storage_iterator (until C++20) get_temporary_buffer (until C++20) return_temporary_buffer (until C++20) Garbage collection support declare_reachable (C++11) undeclare_reachable (C++11) declare_no_pointers (C++11) undeclare_no_pointers (C++11) pointer_safety (C++11) get_pointer_safety (C++11) Miscellaneous pointer_traits (C++11) to_address (C++20) addressof (C++11) align (C++11) assume_aligned (C++20) C Library malloc aligned_alloc (C++17) calloc realloc free Low level memory management

 

std::pmr::polymorphic_allocator

Member functions

polymorphic_allocator::polymorphic_allocator

polymorphic_allocator::allocate

polymorphic_allocator::deallocate

polymorphic_allocator::construct

polymorphic_allocator::destroy

polymorphic_allocator::select_on_container_copy_construction

polymorphic_allocator::resource

Non-member functions

operator==operator!=

 

polymorphic_allocator() noexcept;	(1)
polymorphic_allocator( const polymorphic_allocator& other ) = default;	(2)
template< class U > polymorphic_allocator( const polymorphic_allocator<U>& other ) noexcept;	(3)
polymorphic_allocator( memory_resource* r);	(4)

Constructs a new polymorphic_allocator.

1) Constructs a polymorphic_allocator using the return value of std::pmr::get_default_resource() as the underlying memory resource.

2-3) Constructs a polymorphic_allocator using other.resource() as the underlying memory resource.

4) Constructs a polymorphic_allocator using r as the underlying memory resource. This constructor provides an implicit conversion from memory_resource*.

Parameters

other	-	another polymorphic_allocator to copy from
r	-	pointer to the memory resource to use. May not be null.

Exceptions

4) Throws nothing.

Notes

Copying a container using a polymorphic_allocator will not call the allocator's copy constructor. Instead, the new container will use the return value of select_on_container_copy_construction (a default-constructed polymorphic_allocator) as its allocator.

See also

select_on_container_copy_construction

Create a new polymorphic_allocator for use by a container's copy constructor (public member function)