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

NAME
     std::ranges::ends_with - std::ranges::ends_with

Synopsis
	Defined in header <algorithm>
	Call signature
	template< std::input_iterator I1, std::sentinel_for<I1> S1,

		  std::input_iterator I2, std::sentinel_for<I2> S2,
		  class Pred = ranges::equal_to,
		  class Proj1 = std::identity, class Proj2 = std::identity >
	requires (std::forward_iterator<I1> || std::sized_sentinel_for<S1, I1>)
	&&
     (1) (since
		 (std::forward_iterator<I2>  || std::sized_sentinel_for<S2, I2>)
     C++23)
	&&
		 std::indirectly_comparable<I1, I2, Pred, Proj1, Proj2>
	constexpr bool
	    ends_with( I1 first1, S1 last1, I2 first2, S2 last2, Pred pred = {},

		       Proj1 proj1 = {}, Proj2 proj2 = {} );
	template< ranges::input_range R1, ranges::input_range R2,

		  class Pred = ranges::equal_to,
		  class Proj1 = std::identity, class Proj2 = std::identity >
	requires (ranges::forward_range<R1> || ranges::sized_range<R1>) &&
		 (ranges::forward_range<R2>   ||   ranges::sized_range<R2>)   &&
     (since
		 std::indirectly_comparable<ranges::iterator_t<R1>,
     (2) C++23)
					    ranges::iterator_t<R2>,
					    Pred, Proj1, Proj2>
	constexpr bool
	    ends_with( R1&& r1, R2&& r2, Pred pred = {},

		       Proj1 proj1 = {}, Proj2 proj2 = {} );

	Checks whether the second range matches the suffix of the first range.

	1)  Let  N1  and  N2 be ranges::distance(first1, last1) and ranges::dis-
     tance(first2,
	last2) respectively. If N1 < N2, returns false. Otherwise, returns  true
     if only if
	every element in the range [first2, last2) is equal to the corresponding
     element in
	[first1  +  N1	-  N2, last1). Comparison is done by applying the binary
     predicate pred
	to elements in two ranges projected by proj1 and proj2 respectively.
	2) Same as (1), but uses r1 and r2 as the source ranges, as if using
	ranges::begin(r1) as first1, ranges:begin(r2) as first2, ranges::end(r1)
     as last1,
	and ranges::end(r2) as last2.

	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
	first1, last1 - the range of elements to examine
	r1	      - the range of elements to examine
	first2, last2 - the range of elements to be used as the suffix
	r2	      - the range of elements to be used as the suffix
	pred	       -  the  binary predicate that compares the projected ele-
     ments
	proj1	      - the projection to apply to the elements of the range  to
     examine
	proj2	       - the projection to apply to the elements of the range to
     be used as
			the suffix

Return value
	true if the second range matches the suffix of the  first  range,  false
     otherwise.

Complexity
	Generally  linear: at most min(N1, N2) applications of the predicate and
     both
	projections. The predicate and both projections are not applied if N1  <
     N2.

	If  both  N1 and N2 can be calculated in constant time (i.e. both itera-
     tor-sentinel
	type  pairs  model  sized_sentinel_for,  or  both  range   types   model
     sized_range) and N1 <
	N2, the time complexity is constant.

Possible implementation
	struct ends_with_fn
	{
	    template<std::input_iterator I1, std::sentinel_for<I1> S1,
		     std::input_iterator I2, std::sentinel_for<I2> S2,
		     class Pred = ranges::equal_to,
		     class Proj1 = std::identity, class Proj2 = std::identity>
	    requires  (std::forward_iterator<I1>  || std::sized_sentinel_for<S1,
     I1>) &&
		     (std::forward_iterator<I2>  ||  std::sized_sentinel_for<S2,
     I2>) &&
		     std::indirectly_comparable<I1, I2, Pred, Proj1, Proj2>
	    constexpr  bool operator()(I1 first1, S1 last1, I2 first2, S2 last2,
     Pred pred = {},
				      Proj1 proj1 = {}, Proj2 proj2 = {}) const
	    {
		const auto n1 = ranges::distance(first1, last1);
		const auto n2 = ranges::distance(first2, last2);
		if (n1 < n2)
		    return false;
		ranges::advance(first1, n1 - n2);
		return ranges::equal(std::move(first1), std::move(last1),
				     std::move(first2), std::move(last2),
				     std::move(pred),	       std::move(proj1),
     std::move(proj2));
	    }

	    template<ranges::input_range R1, ranges::input_range R2,
		     class Pred = ranges::equal_to,
		     class Proj1 = std::identity, class Proj2 = std::identity>
	    requires (ranges::forward_range<R1> || ranges::sized_range<R1>) &&
		     (ranges::forward_range<R2> || ranges::sized_range<R2>) &&
		     std::indirectly_comparable<ranges::iterator_t<R1>,
						ranges::iterator_t<R2>,
						Pred, Proj1, Proj2>
	    constexpr bool operator()(R1&& r1, R2&& r2, Pred pred = {},
				      Proj1 proj1 = {}, Proj2 proj2 = {}) const
	    {
		return (*this)(ranges::begin(r1), ranges::end(r1),
			       ranges::begin(r2), ranges::end(r2),
			       std::move(pred), 	       std::move(proj1),
     std::move(proj2));
	    }
	};

	inline constexpr ends_with_fn ends_with {};

Notes
	       Feature-test macro	   Value    Std 	       Feature
	__cpp_lib_ranges_starts_ends_with	     202106L		 (C++23)
     std::ranges::starts_with,
							  std::ranges::ends_with

Example
     // Run this code

      #include <algorithm>
      #include <array>

      static_assert(
	  ! std::ranges::ends_with("for", "cast") &&
	  std::ranges::ends_with("dynamic_cast", "cast") &&
	  ! std::ranges::ends_with("as_const", "cast") &&
	  std::ranges::ends_with("bit_cast", "cast") &&
	  ! std::ranges::ends_with("to_underlying", "cast") &&
	  std::ranges::ends_with(std::array{1, 2, 3, 4}, std::array{3, 4}) &&
	  ! std::ranges::ends_with(std::array{1, 2, 3, 4}, std::array{4, 5})
      );

      int main() {}

See also
	ranges::starts_with checks whether a range starts with another range
	(C++23) 	    (niebloid)
	ends_with	    checks if the string ends with the given suffix
	(C++20) 	    (public member function of
			    std::basic_string<CharT,Traits,Allocator>)
	ends_with	    checks if the string view ends with the given suffix
	(C++20) 		(public     member    function	  of	std::ba-
     sic_string_view<CharT,Traits>)

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