std::ranges::views::slide,std::ranges::slide_view(3)

NAME
std::ranges::views::slide,std::ranges::slide_view - std::ranges::views::slide,std::ranges::slide_view

Synopsis
   Defined in header <ranges>
   template< ranges::forward_range V >
       requires ranges::view<V> (1) (since C++23)
   class slide_view
       : public ranges::view_interface<slide_view<V>>
   namespace views {
       inline constexpr /* unspecified */ slide = /* unspecified (2) (since C++23)
   */;
   }
   Call signature
   template< ranges::viewable_range R >
   constexpr ranges::view auto slide( R&& r, (since C++23)
   ranges::range_difference_t<R> n );
   template< class DifferenceType >
   constexpr /* range adaptor object */ slide( DifferenceType&& (since C++23)
   n );
   Helper concepts
   template< class V >
   concept __slide_caches_nothing = (3) (exposition only*)
       ranges::random_access_range<V> && ranges::sized_range<V>;
   template< class V >
   concept __slide_caches_last =
       !__slide_caches_nothing<V> && (4) (exposition only*)
       ranges::bidirectional_range<V> &&
   ranges::common_range<V>;
   template< class V >
   concept __slide_caches_first = (5) (exposition only*)
       !__slide_caches_nothing<V> && !__slide_caches_last<V>;
   1) slide_view is a range adaptor that takes a view and a number n and produces a
   view whose m ^th element (a "window") is a view over the m ^th through (m + n -
   1) ^th elements of the original view.
   Let s be the size of the original view. Then the size of produced view is:
     * s - n + 1, if s >= n,
     * 0 otherwise, and the resulting view is empty.
   2) The name views::slide denotes a RangeAdaptorObject. Given subexpressions e and n,
   the expression views::slide(e, n) is expression-equivalent to slide_view(e, n).
   If n is not greater than 0, the behavior is undefined.
   slide_view always models forward_range, and models bidirectional_range,
   random_access_range, or sized_range if adapted view type models the corresponding
   concept.

Member functions
   constructor constructs a slide_view
   (C++23) (public member function)
   begin returns an iterator to the beginning
   (C++23) (public member function)
   end returns an iterator or a sentinel to the end
   (C++23) (public member function)
   size returns the number of elements. Provided only if the underlying
   (C++23) (adapted) range satisfies sized_range.
                 (public member function)
         Inherited from std::ranges::view_interface
   empty returns whether the derived view is empty. Provided if it satisfies
   (C++20) sized_range or forward_range.
                 (public member function of std::ranges::view_interface<D>)
   cbegin returns a constant iterator to the beginning of the range.
   (C++23) (public member function of std::ranges::view_interface<D>)
   cend returns a sentinel for the constant iterator of the range.
   (C++23) (public member function of std::ranges::view_interface<D>)
   operator bool returns whether the derived view is not empty. Provided if
   (C++20) ranges::empty is applicable to it.
                 (public member function of std::ranges::view_interface<D>)
   front returns the first element in the derived view. Provided if it
   (C++20) satisfies forward_range.
                 (public member function of std::ranges::view_interface<D>)
   back returns the last element in the derived view. Provided if it satisfies
   (C++20) bidirectional_range and common_range.
                 (public member function of std::ranges::view_interface<D>)
   operator[] returns the n^th element in the derived view. Provided if it satisfies
   (C++20) random_access_range.
                 (public member function of std::ranges::view_interface<D>)
   Deduction guides
   Nested classes
   iterator the iterator type
   (C++23) (exposition-only member class template*)
   sentinel the sentinel type used when slide_view is not a common_range
   (C++23) (exposition-only member class template*)
   Helper templates
   template< class V >
   inline constexpr bool ranges::enable_borrowed_range<slide_view<V>> = (since C++23)
       ranges::enable_borrowed_range<V>;
   This specialization of ranges::enable_borrowed_range makes slide_view satisfy
   borrowed_range when the underlying view satisfies it.

Notes
   There are similarities between ranges::adjacent_view and ranges::slide_view:
     * Both create a "sliding window" of size N.
     * Both have the same size S - N + 1, where S is the size of an adapted view such
       that S >= N > 0.
   The differences between these adapters are:
                  View adaptor value_type The window size N
              ranges::adjacent_view A std::tuple object A template parameter
              ranges::slide_view A range A runtime parameter
     Feature-test macro Value Std Feature
   __cpp_lib_ranges_slide 202202L (C++23) std::ranges::slide_view

Example
// Run this code
 #include <algorithm>
 #include <iostream>
 #include <ranges>
 auto print_subrange = [](std::ranges::viewable_range auto&& r)
 {
     std::cout << '[';
     for (char space[]{0,0}; auto elem : r)
         std::cout << space << elem, *space = ' ';
     std::cout << "] ";
 };
 int main()
 {
     const auto v = {1, 2, 3, 4, 5, 6};
     std::cout << "All sliding windows of width:\n";
     for (const unsigned width : std::views::iota(1U, 1U + v.size()))
     {
         auto const windows = v | std::views::slide(width);
         std::cout << "W = " << width << ": ";
         std::ranges::for_each(windows, print_subrange);
         std::cout << '\n';
     }
 }

Output:
 All sliding windows of width W:
 W = 1: [1] [2] [3] [4] [5] [6]
 W = 2: [1 2] [2 3] [3 4] [4 5] [5 6]
 W = 3: [1 2 3] [2 3 4] [3 4 5] [4 5 6]
 W = 4: [1 2 3 4] [2 3 4 5] [3 4 5 6]
 W = 5: [1 2 3 4 5] [2 3 4 5 6]
 W = 6: [1 2 3 4 5 6]

References
     * C++23 standard (ISO/IEC 14882:2023):
     * 26.7.29 Slide view [range.slide]

See also
   ranges::adjacent_view a view consisting of tuples of references to adjacent elements
   views::adjacent of the adapted view
   (C++23) (class template) (range adaptor object)
   ranges::chunk_view a range of views that are N-sized non-overlapping successive
   views::chunk chunks of the elements of another view
   (C++23) (class template) (range adaptor object)