std::ranges::common_view<V>::begin
constexpr auto begin(); |
(1) | (since C++20) |
constexpr auto begin() const requires range<const V>; |
(2) | (since C++20) |
common_view, that is:
-
ranges::begin(base_), if bothranges::random_access_range<V>andranges::sized_range<V>are satisfied, -
std::common_iterator<ranges::iterator_t<V>, ranges::sentinel_t<V>>(ranges::begin(base_))otherwise.
base_ (the name is for exposition only purposes) is the underlying view.
2) Same as
(1), but
V is const-qualified.
Parameters
(none).
Return value
An iterator to the beginning of the underlying view.
Example
#include <iostream>
#include <numeric>
#include <ranges>
#include <string_view>
int main()
{
constexpr auto common = std::views::iota(1)
| std::views::take(3)
| std::views::common
;
for (int i{}; int e : common) { std::cout << (i++ ? " + " : "") << e; }
std::cout << " = " << std::accumulate(common.begin(), common.end(), 0) << '\n';
}
Output:
1 + 2 + 3 = 6
See also
|
(C++20)
|
returns an iterator to the end (public member function) |
|
(C++20)
|
returns an iterator to the beginning of a range (customization point object) |
|
(C++20)
|
returns a sentinel indicating the end of a range (customization point object) |
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