std::ranges::stride_view<V>::size

 

C++

Compiler support

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Standard library

Standard library headers

Named requirements

Feature test macros (C++20)

Language support library

Concepts library (C++20)

Metaprogramming library (C++11)

Diagnostics library

General utilities library

Strings library

Containers library

Iterators library

Ranges library (C++20)

Algorithms library

Numerics library

Localizations library

Input/output library

Filesystem library (C++17)

Regular expressions library (C++11)

Concurrency support library (C++11)

Technical specifications

Symbols index

External libraries

 

Ranges library

Range access
begin cbegin end cend	rbegin crbegin rend crend	size ssize data cdata	empty
Range conversions
to (C++23)
Range primitives
range_size_trange_difference_trange_value_trange_reference_t	iterator_tconst_iterator_tsentinel_tconst_sentinel_t (C++23)(C++23)	range_const_reference_trange_rvalue_reference_trange_common_reference_t (C++23)	elements_of (C++23)
Dangling iterator handling
dangling	borrowed_iterator_t	borrowed_subrange_t
Range concepts
range borrowed_range sized_range constant_range (C++23)	common_range view viewable_range	input_range output_range forward_range	bidirectional_range random_access_range contiguous_range
Views
view_interface	subrange
Range factories
empty_viewviews::empty single_viewviews::single	iota_viewviews::iota repeat_viewviews::repeat (C++23)(C++23)	basic_istream_viewviews::istream
Range adaptors
views::all_tviews::all ref_view owning_view as_rvalue_viewviews::as_rvalue (C++23)(C++23) filter_viewviews::filter transform_viewviews::transform take_viewviews::take take_while_viewviews::take_while	drop_viewviews::drop drop_while_viewviews::drop_while join_viewviews::join join_with_viewviews::join_with (C++23)(C++23) lazy_split_viewviews::lazy_split split_viewviews::split views::counted common_viewviews::common	reverse_viewviews::reverse as_const_viewviews::as_const (C++23)(C++23) elements_viewviews::elements keys_viewviews::keys values_viewviews::values enumerate_viewviews::enumerate (C++23)(C++23) zip_viewviews::zip (C++23)(C++23) zip_transform_viewviews::zip_transform (C++23)(C++23)	adjacent_viewviews::adjacent (C++23)(C++23) views::pairwise (C++23) adjacent_transform_viewviews::adjacent_transform (C++23)(C++23) views::pairwise_transform (C++23) chunk_viewviews::chunk (C++23)(C++23) slide_viewviews::slide (C++23)(C++23) chunk_by_viewviews::chunk_by (C++23)(C++23) stride_viewviews::stride (C++23)(C++23) cartesian_product_viewviews::cartesian_product (C++23)(C++23)
Range generators
std::generator (C++23)
Range adaptor objects
Range adaptor closure objects
range_adaptor_closure (C++23)
Helper items
copyable-box movable-box (until C++23)(C++23)	simple-view non-propagating-cache

 

std::ranges::stride_view

Member functions

stride_view::stride_view (C++23)

stride_view::base (C++23)

stride_view::stride (C++23)

stride_view::begin (C++23)

stride_view::end (C++23)

stride_view::size (C++23)

Deduction guides

Iterator

Member functions

stride_view::iterator::iterator (C++23)

stride_view::iterator::base (C++23)

stride_view::iterator::operator* (C++23)

stride_view::iterator::operator[] (C++23)

stride_view::iterator::operator++ stride_view::iterator::operator++(int) stride_view::iterator::operator-- stride_view::iterator::operator--(int) stride_view::iterator::operator+= stride_view::iterator::operator-= (C++23)(C++23)(C++23)(C++23)(C++23)(C++23)

Non-member functions

operator==(std::default_sentinel_t) operator==(stride_view::iterator) operator<(stride_view::iterator) operator>(stride_view::iterator) operator<=(stride_view::iterator) operator>=(stride_view::iterator) operator<=>(stride_view::iterator) (C++23)(C++23)(C++23)(C++23)(C++23)(C++23)(C++23)

operator+(stride_view::iterator) operator-(stride_view::iterator) (C++23)(C++23)

iter_move(stride_view::iterator) (C++23)

iter_swap(stride_view::iterator) (C++23)

 

constexpr auto size() requires ranges::sized_range<V>;		(since C++23)
constexpr auto size() const requires ranges::sized_range<const V>;		(since C++23)

Returns the number of elements.

Let base_ be the underlying view and stride_ be the stored stride value. Equivalent to:

return __to_unsigned_like(__div_ceil(ranges::distance(base_), stride_));

Parameters

(none)

Return value

The number of elements. The returned value is calculated as if by expression

(ranges::size(base_) / stride_) + ((ranges::size(base_) % stride_ ? 1 : 0).

Example

A link to test: Compiler Explorer

Run this code

#include <ranges>
#include <forward_list>
 
int main()
{
    namespace vs = std::views;
    constexpr static auto v = {1, 2, 3, 4, 5};
    static_assert(
        vs::stride(v, 1).size() == 5 and
        vs::stride(v, 2).size() == 3 and
        vs::stride(v, 3).size() == 2 and
        vs::stride(v, 4).size() == 2 and
        vs::stride(v, 5).size() == 1 and
        vs::stride(v, 6).size() == 1
    );
 
    std::forward_list list{v};
//  auto s = vs::stride(list, 2).size(); // Error: not a sized_range
}

See also

ranges::size (C++20)	returns an integer equal to the size of a range (customization point object)
ranges::ssize (C++20)	returns a signed integer equal to the size of a range (customization point object)