std::ranges::lazy_split_view<V, Pattern>::outer_iterator
template< bool Const > struct /*outer_iterator*/; |
(since C++20) (exposition only*) |
|
The return type of lazy_split_view::begin
, and of lazy_split_view::end
when the underlying view is a common_range
and forward_range
.
If either V
or Pattern
is not a simple view (e.g. if ranges::iterator_t<const V> is invalid or different from ranges::iterator_t<V>), Const
is true for iterators returned from the const overloads, and false otherwise. If V
is a simple view, Const
is true if and only if V
is a forward_range
.
[edit] Member types
Member | Definition |
Parent
|
maybe-const <Const, ranges::lazy_split_view>(exposition-only member type*) |
Base
|
maybe-const <Const, V>(exposition-only member type*) |
iterator_concept (C++20)
|
std::forward_iterator_tag if Base models forward_range , otherwise std::input_iterator_tag
|
iterator_category (C++20)(conditionally present) |
std::input_iterator_tag if Base models forward_range . Not present otherwise.
|
(C++20) |
the value type of the outer_iterator (public member class) |
difference_type (C++20)
|
ranges::range_difference_t<Base> |
[edit] Data members
Member | Definition |
Parent* parent_ (private)
|
A pointer to the parent object lazy_split_view (exposition-only member object*) |
ranges::iterator_t<Base> current_ (private) (present only if V models forward_range )
|
An iterator into the underlying view (exposition-only member object*) |
bool trailing_empty_ (private)
|
A flag that indicates whether an empty trailing subrange (if any) was reached (exposition-only member object*) |
[edit] Member functions
(constructor) (C++20) |
constructs an iterator (public member function) |
operator* (C++20) |
returns the current subrange (public member function) |
operator++operator++(int) (C++20) |
advances the iterator (public member function) |
cur (C++20) |
returns conditionally a reference to the current_ (if present) or to the *parent_->current_(exposition-only member function*) |
[edit] Member functions
std::ranges::lazy_split_view::outer_iterator ::outer_iterator
/*outer_iterator*/() = default; |
(1) | (since C++20) |
constexpr explicit /*outer_iterator*/( Parent& parent ) requires (!ranges::forward_range<Base>); |
(2) | (since C++20) |
constexpr /*outer_iterator*/( Parent& parent, ranges::iterator_t<Base> current ) |
(3) | (since C++20) |
constexpr /*outer_iterator*/( /*outer_iterator*/<!Const> i ) requires Const && std::convertible_to<ranges::iterator_t<V>, |
(4) | (since C++20) |
- parent_ = nullptr;,
- current_ = iterator_t<Base>(); (present only if
V
modelsforward_range
),
parent_
with i.parent_, current_
with std::move(i.current_), and trailing_empty_
with t.trailing_empty_.The trailing_empty_
is initialized with its default member initializer to false.
std::ranges::lazy_split_view::outer_iterator ::operator*
constexpr value_type operator*() const; |
(since C++20) | |
Equivalent to return value_type{*this};.
std::ranges::lazy_split_view::outer_iterator ::operator++
constexpr /*outer_iterator*/& operator++(); |
(1) | (since C++20) |
constexpr decltype(auto) operator++(int); |
(2) | (since C++20) |
const auto end = ranges::end(parent_->base_); if (/*cur*/() == end) { trailing_empty_ = false; return *this; } const auto [pbegin, pend] = ranges::subrange{parent_->pattern_}; if (pbegin == pend) ++/*cur*/(); else if constexpr (/*tiny_range*/<Pattern>) { /*cur*/() = ranges::find(std::move(/*cur*/()), end, *pbegin); if (/*cur*/() != end) { ++/*cur*/(); if (/*cur*/() == end) trailing_empty_ = true; } } else { do { auto [b, p] = ranges::mismatch(/*cur*/(), end, pbegin, pend); if (p == pend) { /*cur*/() = b; if (/*cur*/() == end) trailing_empty_ = true; break; // The pattern matched; skip it } } while (++/*cur*/() != end); } return *this;
if constexpr (ranges::forward_range<Base>) { auto tmp = *this; ++*this; return tmp; } else { ++*this; // no return statement }
std::ranges::lazy_split_view::outer_iterator ::cur ()
constexpr auto& /*cur*/() noexcept; |
(1) | (since C++20) (exposition only*) |
constexpr auto& /*cur*/() const noexcept; |
(2) | (since C++20) (exposition only*) |
This convenience member function is referred to from /*outer_iterator*/::operator++(), from the non-member operator==(const /*outer_iterator*/&, std::default_sentinel_t), and from some member functions of the possible implementation of inner_iterator
.
if constexpr (ranges::forward_range<V>) return current_; else return *parent->current_;
[edit] Non-member functions
operator== (C++20) |
compares the underlying iterators or the underlying iterator and std::default_sentinel (function) |
operator==(std::ranges::split_view::outer_iterator)
friend constexpr bool operator==( const /*outer_iterator*/& x, const /*outer_iterator*/& y ) |
(1) | (since C++20) |
friend constexpr bool operator==( const /*outer_iterator*/& x, std::default_sentinel_t ); |
(2) | (since C++20) |
The !=
operator is synthesized from operator==
.
These functions are not visible to ordinary unqualified or qualified lookup, and can only be found by argument-dependent lookup when std::ranges::split_view::outer_iterator
is an associated class of the arguments.
[edit] Defect reports
The following behavior-changing defect reports were applied retroactively to previously published C++ standards.
DR | Applied to | Behavior as published | Correct behavior |
---|---|---|---|
LWG 3904 | C++20 | trailing_empty_ was not initialized in constructor (4)
|
initialized |