std::ranges::chunk_by_view<V,Pred>::begin
constexpr /*iterator*/ begin(); | (since C++23) |
Returns an iterator to the first element of the chunk_by_view.
Equivalent to:
ranges::iterator_t<V> iter;
if (begin_.has_value())
iter = begin_.value();
else
{
iter = /*find_next*/(ranges::begin(base()));
begin_ = iter; // caching
}
return /*iterator*/(*this, ranges::begin(base()), iter);
The behavior is undefined if the underlying predicate pred_ does not contain a value.
Parameters
(none)
Return value
Iterator to the first element.
Notes
In order to provide the amortized constant-time complexity required by the range concept, this function caches the result within the data member begin_ for use on subsequent calls.
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) |
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