std::pmr::polymorphic_allocator<T>::new_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 (deprecated in C++20)

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, class... CtorArgs > [[nodiscard]] U* new_object( CtorArgs&&... ctor_args );		(since C++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

allocate_bytes (C++20)	allocate raw aligned memory from the underlying resource (public member function)
allocate_object (C++20)	allocates raw memory suitable for an object or an array (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)