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std::uninitialized_move(3)    C++ Standard Libary   std::uninitialized_move(3)

NAME
       std::uninitialized_move - std::uninitialized_move

Synopsis
	  Defined in header <memory>
	  template< class InputIt, class NoThrowForwardIt >

	  NoThrowForwardIt  uninitialized_move(	 InputIt  first, InputIt last,
       (1) (since C++17)

					       NoThrowForwardIt	d_first	);
	  template< class ExecutionPolicy, class ForwardIt, class
	  NoThrowForwardIt >

	  NoThrowForwardIt   uninitialized_move(   ExecutionPolicy&&   policy,
       (2) (since C++17)
					       ForwardIt first,	ForwardIt
	  last,

					       NoThrowForwardIt	d_first	);

	  1)  Moves  elements from the range [first, last) to an uninitialized
       memory area
	  beginning at d_first as if by
	  for (; first != last;	++d_first, (void) ++first)
	      ::new (static_cast<void*>(std::addressof(*d_first)))
		  typename
	  std::iterator_traits<NoThrowFor-
       wardIt>::value_type(std::move(*first));
	  If an	exception is thrown during the initialization, some objects in
       [first, last)
	  are left in a	valid but unspecified state, and the  objects  already
       constructed are
	  destroyed in an unspecified order.

	  If   d_first	 +   [0,  std::distance(first,	last))	overlaps  with
       (since C++20)
	  [first, last), the behavior is undefined.

	  2) Same as (1), but executed according to policy. This overload par-
       ticipates in
	  overload resolution only if

	  std::is_execution_policy_v<std::decay_t<ExecutionPolicy>>  is	 true.
       (until
										    C++20)
	  std::is_execution_policy_v<std::remove_cvref_t<ExecutionPolicy>>  is
       true. (since
										    C++20)

Parameters
	  first, last		-	 the range of the elements to move
	  d_first		-	  the  beginning  of  the  destination
       range
	  policy		-	 the execution policy to use. See exe-
       cution policy for
					 details.

Type requirements
	  -
	  InputIt must meet the	requirements of	LegacyInputIterator.
	  -
	  ForwardIt must meet the requirements of LegacyForwardIterator.
	  -
	  NoThrowForwardIt  must  meet the requirements	of LegacyForwardItera-
       tor.
	  -
	  No increment,	assignment, comparison,	or indirection	through	 valid
       instances of
	  NoThrowForwardIt may throw exceptions.

Return value
	  Iterator to the element past the last	element	moved.

Complexity
	  Linear in the	distance between first and last.

Exceptions
	  The overload with a template parameter named ExecutionPolicy reports
       errors as
	  follows:

	    *  If  execution  of  a  function invoked as part of the algorithm
       throws an exception
	      and ExecutionPolicy is one of the	standard policies, std::termi-
       nate is called.
	      For any other ExecutionPolicy, the behavior  is  implementation-
       defined.
	    *  If  the	algorithm  fails to allocate memory, std::bad_alloc is
       thrown.

Possible implementation
       template<class InputIt, class NoThrowForwardIt> NoThrowForwardIt	unini-
       tialized_move(InputIt first, InputIt last, NoThrowForwardIt d_first) {
	   using    Value    =	  typename    std::iterator_traits<NoThrowFor-
       wardIt>::value_type;
	   NoThrowForwardIt current = d_first;
	   try
	   {
	       for (; first != last; ++first, (void) ++current)
		   ::new	(static_cast<void*>(std::addressof(*current)))
       Value(std::move(*first));
	       return current;
	   }
	   catch (...)
	   {
	       std::destroy(d_first, current);
	       throw;
	   } }

Example
       // Run this code

	#include <cstdlib>
	#include <iomanip>
	#include <iostream>
	#include <memory>
	#include <string>

	void print(auto	rem, auto first, auto last)
	{
	    for	(std::cout << rem; first != last; ++first)
		std::cout << std::quoted(*first) << ' ';
	    std::cout << '\n';
	}

	int main()
	{
	    std::string	in[]{"Home", "Work!"};
	    print("initially, in: ", std::begin(in), std::end(in));

	    if (
		constexpr auto sz = std::size(in);
		void*	 out	=     std::aligned_alloc(alignof(std::string),
       sizeof(std::string) * sz))
	    {
		try
		{
		    auto first{static_cast<std::string*>(out)};
		    auto last{first + sz};
		    std::uninitialized_move(std::begin(in),	 std::end(in),
       first);

		    print("after move, in: ", std::begin(in), std::end(in));
		    print("after move, out: ", first, last);

		    std::destroy(first,	last);
		}
		catch (...)
		{
		    std::cout << "Exception!\n";
		}
		std::free(out);
	    }
	}

Possible output:
	initially, in: "Home" "Work!"
	after move, in:	"" ""
	after move, out: "Home"	"Work!"

	  Defect reports

	  The following	behavior-changing defect reports were applied retroac-
       tively to
	  previously published C++ standards.

	     DR	     Applied	to		   Behavior    as    published
       Correct behavior
	  LWG  3870  C++20	this algorithm might create objects on a const
       kept disallowed
			      storage

See also
				     copies a range of objects	to  an	unini-
       tialized	area of
	  uninitialized_copy	     memory
				     (function template)
	  uninitialized_move_n	      moves  a	number of objects to an	unini-
       tialized	area of
	  (C++17)		     memory
				     (function template)
	  ranges::uninitialized_move moves a range of objects to an uninitial-
       ized area of
	  (C++20)		     memory
				     (niebloid)

http://cppreference.com		  2024.06.10	    std::uninitialized_move(3)

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