NAME¶

std::pmr::polymorphic_allocator::new_object - std::pmr::polymorphic_allocator::new_object

Synopsis¶

template< class U, class... CtorArgs > (since C++20)
[[nodiscard]] U* new_object( CtorArgs&&... ctor_args );

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

allocate allocates memory
(public member function of std::pmr::memory_resource)