std::ranges::adjacent_view<V,N>::size
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< cpp | ranges | adjacent view
C++
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std::ranges::adjacent_view
| Member functions | ||||
adjacent_view::size | ||||
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constexpr
auto size(
) requires ranges::sized_range
<V>
;
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(since C++23) | |
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constexpr
auto size(
)
const requires ranges::sized_range
<
const V>
;
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(since C++23) | |
Returns the number of elements.
Let base_ be the underlying view. Equivalent to:
using SizeType = decltype(ranges::size(base_)); using CommonType = ranges::common_type_t<SizeType, std::size_t>; auto size = static_cast<CommonType>(ranges::size(base_)); size -= std::min<CommonType>(size, N - 1); return static_cast<SizeType>(size);
Parameters
(none)
Return value
The number of elements, may be 0 if ranges::size(base_) is less than N
Example
Run this code
#include <ranges> int main() { constexpr static auto v = {1, 2, 3, 4, 5, 6}; constexpr int width1 {4}; constexpr auto view1 {std::views::adjacent<width1>(v)}; static_assert(view1.size() == 3); static_assert(view1.size() == (v.size() - width1 + 1)); constexpr int width2 {8}; constexpr auto view2 {std::views::adjacent<width2>(v)}; // window is too wide, so view2 has no elements: static_assert(view2.size() == 0); }
See also
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(C++20)
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returns an integer equal to the size of a range (customization point object) |
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(C++20)
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returns a signed integer equal to the size of a range (customization point object) |