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

NAME
       std::raw_storage_iterator - std::raw_storage_iterator

Synopsis
	  Defined in header <memory>
	  template< class OutputIt, class T >

	  class	 raw_storage_iterator					  (un-
       til C++17)

	      :	public std::iterator<std::output_iterator_tag, void,
	  void,	void, void>;
	  template<	  class	      OutputIt,	       class	    T	     >
       (since C++17)
	  class	raw_storage_iterator;					 (dep-
       recated in C++17)
									 (re-
       moved in	C++20)

	  The  output iterator std::raw_storage_iterator makes it possible for
       standard
	  algorithms to	store results in uninitialized	memory.	 Whenever  the
       algorithm writes
	  an  object  of  type	T  to the dereferenced iterator, the object is
       copy-constructed
	  into the location in the uninitialized storage pointed to by the it-
       erator. The
	  template parameter OutputIt is any type that meets the  requirements
       of
	  LegacyOutputIterator	and has	operator* defined to return an object,
       for which
	  operator& returns an object of type T*. Usually, the type T* is used
       as OutputIt.

Type requirements
	  -
	  OutputIt must	meet the requirements of LegacyOutputIterator.

Member functions
	  constructor	  creates a new	raw_storage_iterator
			  (public member function)
	  operator=	  constructs an	object at the pointed-to  location  in
       the buffer
			  (public member function)
	  operator*	  dereferences the iterator
			  (public member function)
	  operator++	  advances the iterator
	  operator++(int) (public member function)
	  base		  provides access to the wrapped iterator
	  (since C++17)	  (public member function)

Member types
	  Member type	    Definition
	  iterator_category std::output_iterator_tag
	  value_type	    void
	  difference_type   void	   (until C++20)
			    std::ptrdiff_t (since C++20)
	  pointer	    void
	  reference	    void

	  Member types iterator_category, value_type, difference_type, pointer
	  and  reference  are  required	 to  be	 obtained  by  inheriting from
       (until C++17)
	  std::iterator<std::output_iterator_tag, void,	void, void, void>.

Note
	  std::raw_storage_iterator was	deprecated primarily  because  of  its
       exception-unsafe
	  behavior.  Unlike  std::uninitialized_copy, it doesn't handle	excep-
       tions during
	  operations like std::copy safely, potentially	 leading  to  resource
       leaks due to a
	  lack	of tracking the	number of successfully constructed objects and
       their proper
	  destruction in the presence of exceptions.

Example
       // Run this code

	#include <algorithm>
	#include <iostream>
	#include <memory>
	#include <string>

	int main()
	{
	    const std::string s[] = {"This", "is", "a",	"test",	"."};
	    std::string* p = std::allocator<std::string>().allocate(5);

	    std::copy(std::begin(s), std::end(s),
		      std::raw_storage_iterator<std::string*,
       std::string>(p));

	    for	(std::string* i	= p; i != p + 5; ++i)
	    {
		std::cout << *i	<< '\n';
		i->~basic_string<char>();
	    }
	    std::allocator<std::string>().deallocate(p,	5);
	}

Output:
	This
	is
	a
	test
	.

See also
	  allocator_traits	   provides information	about allocator	types
	  (C++11)		   (class template)
	  scoped_allocator_adaptor implements multi-level allocator for	multi-
       level containers
	  (C++11)		   (class template)
	  uses_allocator	   checks if the specified type	supports uses-
       allocator
	  (C++11)		   construction
				   (class template)

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

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