std::ranges::views::slide, std::ranges::slide_view
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C++
Feature test macros (C++20)
Concepts library (C++20)
Metaprogramming library (C++11)
Ranges library (C++20)
Filesystem library (C++17)
Concurrency support library (C++11)
Execution control library (C++26)
Ranges library
(exposition-only member object*)
returns the approximate size of the resulting
(public member function) [edit]
returns a constant iterator to the beginning of the range
(public member function of
returns a sentinel for the constant iterator of the range
(public member function of
the sentinel type used when
(exposition-only member class template*)
(C++23)(C++23)
(C++23)(C++23)
(C++23)(C++23)
(C++26)(C++26)
(C++23)(C++23)
(C++23)(C++23)
(C++23)(C++23)
(C++23)(C++23)
(C++23)(C++23)
(C++23)
(C++23)(C++23)
(C++23)
(C++23)(C++23)
slide_viewviews::slide
(C++23)(C++23)
(C++23)(C++23)
(C++23)(C++23)
(C++23)(C++23)
(C++23)
std::ranges::slide_view
(C++26)
Member functions
Non-member functions
Member functions
Non-member functions
Defined in header
<ranges>
template< ranges::forward_range V >
(1)
(since C++23)
requires ranges::view <V>
class slide_view
namespace views {
(2)
(since C++23)
inline constexpr /* unspecified */ slide = /* unspecified */;
Call signature
template< ranges::viewable_range R >
constexpr ranges::view auto slide( R&& r, ranges::range_difference_t <R> n );
(since C++23)
constexpr ranges::view auto slide( R&& r, ranges::range_difference_t <R> n );
template< class DifferenceType >
constexpr /* range adaptor object */ slide( DifferenceType&& n );
(since C++23)
constexpr /* range adaptor object */ slide( DifferenceType&& n );
Helper concepts
template< class V >
(3)
(exposition only*)
concept /*slide-caches-nothing*/ =
template< class V >
(4)
(exposition only*)
concept /*slide-caches-last*/ =
!/*slide-caches-nothing*/<V> &&
template< class V >
(5)
(exposition only*)
concept /*slide-caches-first*/ =
1)
slide_view is a range adaptor that takes a view and a number n and produces a view whose mth element (a "window") is a view over [m, m + n - 1] 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.
Contents
[edit] Data members
Member
Description
V base_
the underlying view(exposition-only member object*)
non-propagating-cache <ranges::iterator_t <V>>
(present only if
(exposition-only member object*)
cached_begin_ (present only if
V models the slide-caches-first )
an object that caches the result of begin() (exposition-only member object*)
non-propagating-cache <ranges::iterator_t <V>>
(present only if
(exposition-only member object*)
cached_end_ (present only if
V models the slide-caches-last )
an object that caches the result of end() (exposition-only member object*)
[edit] Member functions
returns the number of elements, provided only if the underlying (adapted) range satisfies
(public member function) [edit]
sized_range (public member function) [edit]
(C++26)
approximately_sized_range (public member function) [edit]
Inherited from std::ranges::view_interface
returns whether the derived view is empty, provided only if it satisfies
(public member function of
sized_range or forward_range (public member function of
std::ranges::view_interface<D>) [edit]
(C++23)
(public member function of
std::ranges::view_interface<D>) [edit]
(C++23)
(public member function of
std::ranges::view_interface<D>) [edit]
returns whether the derived view is not empty, provided only if ranges::empty is applicable to it
(public member function of
(public member function of
std::ranges::view_interface<D>) [edit]
returns the first element in the derived view, provided if it satisfies
(public member function of
forward_range (public member function of
std::ranges::view_interface<D>) [edit]
returns the last element in the derived view, provided only if it satisfies
(public member function of
bidirectional_range and common_range (public member function of
std::ranges::view_interface<D>) [edit]
returns the
(public member function of
nth element in the derived view, provided only if it satisfies random_access_range (public member function of
std::ranges::view_interface<D>) [edit]
[edit] Deduction guides
[edit] Nested classes
(C++23)
slide_view is not a common_range (exposition-only member class template*)
[edit] Helper templates
template< class V >
(since C++23)
constexpr bool ranges::enable_borrowed_range <slide_view<V>> =
This specialization of ranges::enable_borrowed_range makes slide_view satisfy borrowed_range when the underlying view satisfies it.
[edit] Notes
There are similarities between ranges::adjacent_view and ranges::slide_view:
- Both create "sliding window" of size
N. - Both have the same size
S - N + 1, whereSis the size of an adaptedviewsuch thatS >= N > 0.
The following table shows the differences between these adaptors:
| View adaptor | value_type |
The window size N
|
|---|---|---|
| ranges::adjacent_view | std::tuple | A template parameter |
| ranges::slide_view | ranges::range | A runtime argument |
| Feature-test macro | Value | Std | Feature |
|---|---|---|---|
__cpp_lib_ranges_slide |
202202L |
(C++23) | std::ranges::slide_view
|
[edit] Example
Run this code
#include <algorithm> #include <initializer_list> #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]
[edit] References
- C++23 standard (ISO/IEC 14882:2024):
- 26.7.29 Slide view [range.slide]
[edit] See also
a
(class template) (range adaptor object)[edit]
view consisting of tuples of references to adjacent elements of the adapted view(class template) (range adaptor object)[edit]