std::experimental::pmr::polymorphic_allocator

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Library fundamentals

experimental::optional
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experimental::default_searcherexperimental::make_default_searcher
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Type-erased and polymorphic allocators
Variable templates for type traits

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Polymorphic allocator library

polymorphic_allocator
Convenience aliases for containers using`polymorphic_allocator`
Memory resource classes
memory_resource
synchronized_pool_resource
unsynchronized_pool_resource
monotonic_buffer_resource
resource_adaptor
Global memory resources
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get_default_resource
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Type-erased allocator support for existing classes
function
packaged_task
promise

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std::experimental::pmr::polymorphic_allocator

Member functions
polymorphic_allocator::polymorphic_allocator
polymorphic_allocator::operator=
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!=

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Merged into ISO C++ The functionality described on this page was merged into the mainline ISO C++ standard as of 3/2016, seestd::pmr::polymorphic_allocator(since C++17)

Defined in header`<experimental/memory_resource>`
template<class T> class polymorphic_allocator;		(library fundamentals TS)

The class templatestd::experimental::pmr::polymorphic_allocator is anAllocator whose allocation behavior depends on the memory resource it is constructed with. Thus, different instances ofpolymorphic_allocator can exhibit entirely different allocation behavior. This runtime polymorphism allows objects usingpolymorphic_allocator to behave as if they used different allocator types at run time despite the identical static allocator type.

[edit]Member types

Member type	definition
`value_type`	`T`

[edit]Member functions

(constructor)	constructs a`polymorphic_allocator` (public member function)[edit]
(destructor) (implicitly declared)	implicitly declared destructor (public member function)[edit]
operator=	copy assignment operator (public member function)[edit]
Public member functions
allocate	allocate memory (public member function)[edit]
deallocate	deallocate memory (public member function)[edit]
construct	constructs an object in allocated storage (public member function)[edit]
destroy	destroys an object in allocated storage (public member function)[edit]
select_on_container_copy_construction	create a new`polymorphic_allocator` for use by a container's copy constructor (public member function)[edit]
resource	returns a pointer to the underlying memory resource (public member function)[edit]