std::uninitialized_construct_using_allocator

 

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Defined in header <memory>
template< class T, class Alloc, class... Args > constexpr T* uninitialized_construct_using_allocator( T* p,                                                       const Alloc& alloc,                                                       Args&&... args );		(since C++20)

Creates an object of the given type T by means of uses-allocator construction at the uninitialized memory location indicated by p.

Equivalent to

return std::apply(
    [&]<class... Xs>(Xs&&...xs)
    {
        return std::construct_at(p, std::forward<Xs>(xs)...);
    },
    std::uses_allocator_construction_args<T>(alloc, std::forward<Args>(args)...));

Parameters

p	-	the memory location where the object will be placed
alloc	-	the allocator to use
args	-	the arguments to pass to T's constructor

Return value

Pointer to the newly-created object of type T.

Exceptions

May throw any exception thrown by the constructor of T, typically including std::bad_alloc.

See also

uses_allocator (C++11)	checks if the specified type supports uses-allocator construction (class template)
make_obj_using_allocator (C++20)	creates an object of the given type by means of uses-allocator construction (function template)