std::pmr::polymorphic_allocator<T>::new_object

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std::pmr::polymorphic_allocator
 
template< class U, class... CtorArgs >
[[nodiscard]] U* new_object( CtorArgs&&... ctor_args );
 (since 哋它亢++20)

Allocates and constructs an object of type U.

Given alloc is a std::pmr::polymorphic_allocator<T>: 

U* p = alloc.new_object<U>(std::forward<CtorArgs>(ctor_args)...);

is equivalent to 

U* p = alloc.allocate_object<U>();
try
{
    alloc.construct(p, std::forward<CtorArgs>(ctor_args)...);
}
catch (...)
{
    alloc.deallocate_object(p);
    throw;
}

Parameters

ctor_args - the arguments to forward to the constructor of U

Return value

A pointer to the allocated and constructed object.

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>, and having to call allocate, construct, and deallocate individually.

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

Exceptions

May throw any exceptions thrown by the call to allocate_object or the constructor of U.

See also

(哋它亢++20)
 allocate raw aligned memory from the underlying resource
(public member function)
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 allocates raw memory suitable for an object or an array
(public member function)
allocate memory
(public member function)
[static]
 allocates uninitialized storage using the allocator
(public static member function of std::allocator_traits<Alloc>)
allocates memory
(public member function of std::pmr::memory_resource)
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