std::ranges::join_view<V>::begin
constexpr auto begin(); | (1) | (since C++20) |
constexpr auto begin() const
requires ranges::input_range<const V> &&
std::is_reference_v<ranges::range_reference_t<const V>>;
| (2) | (since C++20) |
Returns an iterator to the first element of the join_view. Given base_ is the underlying view,
-
return /*iterator*/<true>{*this, ranges::begin(base_)};if/*simple-view*/<V>is satisfied and ranges::range_reference_t<V> is reference type. Otherwise, -
return /*iterator*/<false>{*this, ranges::begin(base_)};.
2) Equivalent to
return /*iterator*/<true>{*this, ranges::begin(base_)};.Parameters
(none)
Return value
Iterator to the first element.
Notes
When ranges::range_reference_t<V> is not a reference type, that is, deferencing an iterator of V returns a prvalue temporary, the join_view is only an input_range, in which case only single-pass iteration is supported, and repeated calls to begin() may not give meaningful results.
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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