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

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C++
Dynamic memory management
Uninitialized memory algorithms
Constrained uninitialized memory algorithms
Allocators
Garbage collection support
(C++11) (until C++23)
(C++11) (until C++23)
(C++11) (until C++23)
(C++11) (until C++23)
(C++11) (until C++23)
(C++11) (until C++23)



std::pmr::polymorphic_allocator
template < class U, class ... CtorArgs >
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

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