std::ranges::adjacent_view<V,N>::begin
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                    < cpp | ranges | adjacent view
                    
                                                            
                    |   constexpr auto begin() requires (!__SimpleView<V>);  | 
(1) | (since C++23) | 
|   constexpr auto begin() const requires ranges::range<const V>;  | 
(2) | (since C++23) | 
Returns an iterator to the first element of the adjacent_view.
Let base_ be the underlying view.
1) Equivalent to return /*iterator*/<false>(ranges::begin(base_), ranges::end(base_));.
2) Equivalent to return /*iterator*/<true>(ranges::begin(base_), ranges::end(base_));.
Parameters
(none)
Return value
Iterator to the first element.
Example
Run this code
#include <ranges> #include <tuple> #include <type_traits> int main() { constexpr static auto v = {'A', 'B', 'C', 'D', 'E'}; constexpr auto view = std::views::adjacent<3>(v); constexpr auto tuple = *view.begin(); static_assert ( std::is_same_v < decltype(tuple), const std::tuple<char const&, char const&, char const&> > ); static_assert ( std::get<0>(tuple) == 'A' && std::get<1>(tuple) == 'B' && std::get<2>(tuple) == 'C' ); }
See also
|   returns an iterator or a sentinel to the end  (public member function)  | |
|   (C++20)  | 
 returns an iterator to the beginning of a range (customization point object)  |