std::ranges::adjacent_transform_view<V,F,N>::begin
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                    < cpp | ranges | adjacent transform view
                    
                                                            
                    |   constexpr auto begin();  | 
(1) | (since C++23) | 
|   constexpr auto begin() const     requires ranges::range<const InnerView> &&  | 
(2) | (since C++23) | 
Returns an iterator to the first element of the adjacent_transform_view.
Let inner_ be the underlying ranges::adjacent_view.
1) Equivalent to return /*iterator*/<false>(*this, inner_.begin());.
2) Equivalent to return /*iterator*/<true>(*this, inner_.begin());.
Parameters
(none)
Return value
Iterator to the first element.
Example
Run this code
#include <ranges> int main() { auto sum = [](auto... args) { return (... + args); }; constexpr auto view = std::views::iota(13, 1337) | std::views::adjacent_transform<3>(sum); static_assert(*view.begin() == 42 and 42 == 13 + 14 + 15); }
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)  |