std::pmr::polymorphic_allocator<T>::allocate_object

 

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std::pmr::polymorphic_allocator

Member functions

polymorphic_allocator::polymorphic_allocator

polymorphic_allocator::allocate

polymorphic_allocator::deallocate

polymorphic_allocator::construct

polymorphic_allocator::destroy (C++20/26*)

polymorphic_allocator::allocate_bytes (C++20)

polymorphic_allocator::deallocate_bytes (C++20)

polymorphic_allocator::allocate_object (C++20)

polymorphic_allocator::deallocate_object (C++20)

polymorphic_allocator::new_object (C++20)

polymorphic_allocator::delete_object (C++20)

polymorphic_allocator::select_on_container_copy_construction

polymorphic_allocator::resource

Non-member functions

operator==operator!= (until C++20)

 

template< class U > U* allocate_object( std::size_t n = 1 );		(since C++20)

Allocates storage for n objects of type U using the underlying memory resource.

If std::numeric_limits<std::size_t>::max() / sizeof(U) < n, throws std::bad_array_new_length, otherwise equivalent to return static_cast<U*>(allocate_bytes(n * sizeof(U), alignof(U)));.

Parameters

n

-

the number of objects to allocate storage for

Return value

A pointer to the allocated storage.

Notes

This function was introduced for use with the fully-specialized allocator std::pmr::polymorphic_allocator<>, but it may be useful in any specialization as a shortcut to avoid having to rebind from std::pmr::polymorphic_allocator<T> to std::pmr::polymorphic_allocator<U>.

Since U is not deduced, it must be provided as a template argument when calling this function.

Exceptions

Throws std::bad_array_new_length if n > std::numeric_limits<std::size_t>::max() / sizeof(U); may also be any exceptions thrown by the call to resource()->allocate.

See also

allocate_bytes (C++20)	allocate raw aligned memory from the underlying resource (public member function)
new_object (C++20)	allocates and constructs an object (public member function)
allocate	allocate memory (public member function)
allocate [static]	allocates uninitialized storage using the allocator (public static member function of std::allocator_traits<Alloc>)
allocate	allocates memory (public member function of std::pmr::memory_resource)