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

NAME
       std::ranges::elements_of	- std::ranges::elements_of

Synopsis
	  Defined in header <ranges>
	  template< ranges::range R, class Allocator =
	  std::allocator<std::byte>					     >
       (since C++23)
	  struct elements_of;

	  Encapsulates a range.	Specializations	of elements_of act as a	tag in
       overload	sets
	  to disambiguate when a range should be treated as a sequence	rather
       than a single
	  value.

Template parameters
	  R	    - a	type that satisfies range
	  Allocator - an allocator type	that meets the requirements of Alloca-
       tor

	  Data members

	  Member name Definition
	  range	      a	range of type R
		      (public member object)
		      an  allocator  of	 type Allocator. It has	default	member
       initializer that
	  allocator   value initializes	itself
		      (public member object)

	  All these members are	declared with [[no_unique_address]] attribute.

	  Deduction guide

	  template< class R, class Allocator = std::allocator<std::byte> >
	  elements_of( R&&, Allocator  =  Allocator()  )  ->  elements_of<R&&,
       (since C++23)
	  Allocator>;

Example
       // Run this code

	#include <any>
	#include <generator>
	#include <iostream>
	#include <ranges>
	#include <string_view>

	template<bool Elementwise>
	std::generator<std::any> gen(std::ranges::input_range auto&& r)
	{
	    if constexpr (Elementwise)
		co_yield std::ranges::elements_of(r); // yield each element of
       r
	    else
		co_yield  r;				// yield r as a	single
       value
	}

	int main()
	{
	    auto test =	std::string_view{"test"};

	    for	(std::any a : gen<true>(test))
		std::cout << '[' << std::any_cast<char>(a) << "] ";
	    std::cout << '\n';

	    for	(std::any a : gen<false>(test))
		std::cout << '[' << std::any_cast<std::string_view>(a)	<<  "]
       ";
	    std::cout << '\n';
	}

Output:
	[t] [e]	[s] [t]
	[test]

References
	    * C++23 standard (ISO/IEC 14882:2023):

	    * 26.5.6 Class template elements_of	[range.elementsof]

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

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