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std::ranges::join_view::begin(3) | C++ Standard Libary | std::ranges::join_view::begin(3) |
NAME¶
std::ranges::join_view::begin - std::ranges::join_view::begin
Synopsis¶
constexpr auto begin(); (1) (since
C++20)
constexpr auto begin() const
requires ranges::input_range<const V> && (2) (since
C++20)
std::is_reference_v<ranges::range_reference_t<const
V>>;
Returns an iterator to the first element of the join_view. Given base_ is the
underlying view,
1) Equivalent to return /*iterator*/<true>{*this,
ranges::begin(base_)}; if
__SimpleView<V> is satisfied and ranges::range_reference_t<V> is
reference type.
Otherwise, equivalent to 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¶
This section is incomplete
Reason: no example
See also¶
end returns an iterator or a sentinel to the end
(C++20) (public member function)
ranges::begin returns an iterator to the beginning of a range
(C++20) (customization point object)
Category:¶
* Todo no example
2024.06.10 | http://cppreference.com |