std::ranges::chunk_view<V>::begin
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                     V models only input_range | 
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|   constexpr __outer_iterator begin();  | 
(1) | (since C++23) | 
 V models forward_range | 
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|   constexpr auto begin() requires (!__simple_view<V>);  | 
(2) | (since C++23) | 
|   constexpr auto begin() const requires ranges::forward_range<const V>;  | 
(3) | (since C++23) | 
Returns an iterator to the first element of the chunk_view.
 Let 
base_ denote the underlying view.1) Available only if V models 
input_range. Equivalent to:
current_ = ranges::begin(base_); remainder_ = n_; return __outer_iterator(*this);
current_, remainder_, and n_ are underlying exposition only data members of chunk_view.2) Available if V models 
forward_range. Equivalent to: return iterator<false>(this, ranges::begin(base_));, where iterator is exposition only nested class.3) Available if V models 
forward_range. Equivalent to: return iterator<true>(this, ranges::begin(base_));, where iterator is exposition only nested class.Parameters
(none)
Return value
An iterator to the first element of the chunk_view, as described above.
Example
| This section is incomplete Reason: no example  | 
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)  |