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std::ranges::destroy(3)        C++ Standard Libary	 std::ranges::destroy(3)

NAME
     std::ranges::destroy - std::ranges::destroy

Synopsis
	Defined in header <memory>
	Call signature
	template< no-throw-input-iterator I, no-throw-sentinel-for<I> S >

	    requires  std::destructible<std::iter_value_t<I>>		     (1)
     (since C++20)

	constexpr I destroy( I first, S last ) noexcept;
	template< no-throw-input-range R >

	    requires  std::destructible<ranges::range_value_t<R>>	     (2)
     (since C++20)

	constexpr ranges::borrowed_iterator_t<R> destroy( R&& r )
	noexcept;

	1) Destroys the objects in the range [first, last), as if by

      for (; first != last; ++first)
	  std::ranges::destroy_at(std::addressof(*first));
      return first;

	2)  Same as (1), but uses r as the source range, as if using ranges::be-
     gin(r) as
	first and ranges::end(r) as last.

	The function-like entities described on this page  are	niebloids,  that
     is:

	  *  Explicit  template  argument lists cannot be specified when calling
     any of them.
	  * None of them are visible to argument-dependent lookup.
	  * When any of them are found by normal unqualified lookup as the  name
     to the left
	    of	the  function-call operator, argument-dependent lookup is inhib-
     ited.

	In practice, they may be implemented as function objects, or  with  spe-
     cial compiler
	extensions.

Parameters
	first,	last  - iterator-sentinel pair denoting the range of elements to
     destroy
	r	    - the range to destroy

Return value
	An iterator compares equal to last.

Complexity
	Linear in the distance between first and last.

Possible implementation
	struct destroy_fn
	{
	    template<no-throw-input-iterator I, no-throw-sentinel-for<I> S>
		requires std::destructible<std::iter_value_t<I>>
	    constexpr I operator()(I first, S last) const noexcept
	    {
		for (; first != last; ++first)
		    std::ranges::destroy_at(std::addressof(*first));
		return first;
	    }

	    template<no-throw-input-range R>
		requires std::destructible<std::ranges::range_value_t<R>>
	    constexpr  std::ranges::borrowed_iterator_t<R>   operator()(R&&   r)
     const noexcept
	    {
		return operator()(std::ranges::begin(r), std::ranges::end(r));
	    }
	};

	inline constexpr destroy_fn destroy{};

Example
	The following example demonstrates how to use ranges::destroy to destroy
     a
	contiguous sequence of elements.

     // Run this code

      #include <iostream>
      #include <memory>
      #include <new>

      struct Tracer
      {
	  int value;
	  ~Tracer() { std::cout << value << " destructed\n"; }
      };

      int main()
      {
	  alignas(Tracer) unsigned char buffer[sizeof(Tracer) * 8];

	  for (int i = 0; i < 8; ++i)
	      new(buffer  +  sizeof(Tracer) * i) Tracer{i}; //manually construct
     objects

	  auto ptr = std::launder(reinterpret_cast<Tracer*>(buffer));

	  std::ranges::destroy(ptr, ptr + 8);
      }

Output:
      0 destructed
      1 destructed
      2 destructed
      3 destructed
      4 destructed
      5 destructed
      6 destructed
      7 destructed

See also
	ranges::destroy_n  destroys a number of objects in a range
	(C++20) 	   (niebloid)
	ranges::destroy_at destroys an object at a given address
	(C++20) 	   (niebloid)
	destroy 	   destroys a range of objects
	(C++17) 	   (function template)

http://cppreference.com 	   2024.06.10		 std::ranges::destroy(3)
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