std::pmr::polymorphic_allocator<T>::allocate_object (3) - Linux Manuals

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

NAME

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

Synopsis


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


Allocates storage for n objects of type U using the underlying memory resource.
If SIZE_MAX / sizeof(U) < n, throws std::length_error, 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::polymorphic_allocator<>, but it may be useful in any specialization as a shortcut to avoid having to rebind from std::polymorphic_allocator<T> to std::polymorphic_allocator<U>.
Since U is not deduced, it must be provided as a template argument when calling this function.

Exceptions


Throws std::length_error if n > SIZE_MAX / sizeof(T); may also any exceptions thrown by the call to resource()->allocate.

See also


allocate_bytes Allocate raw aligned memory from the underlying resource
               (public member function)
(C++20)


new_object Allocates and constructs an object
               (public member function)
(C++20)
               Allocate memory
allocate (public member function)


allocate allocates uninitialized storage using the allocator
               (public static member function of std::allocator_traits<Alloc>)
[static]
               allocates memory
allocate (public member function of std::pmr::memory_resource)