std::ranges::lazy_split_view<V, Pattern>::inner_iterator

 

C++

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Standard library headers

Named requirements

Feature test macros (C++20)

Language support library

Concepts library (C++20)

Diagnostics library

Memory management library

Metaprogramming library (C++11)

General utilities library

Containers library

Iterators library

Ranges library (C++20)

Algorithms library

Strings library

Text processing library

Numerics library

Date and time library

Input/output library

Filesystem library (C++17)

Concurrency support library (C++11)

Execution control library (C++26)

Technical specifications

Symbols index

External libraries

 

Ranges library

Range access begin cbegin   end cend rbegin crbegin   rend crend size ssize   data cdata reserve_hint (C++26)   empty

Range conversions std::from_range_t std::from_range (C++23)(C++23)     to (C++23)

Dangling iterator handling dangling borrowed_iterator_t borrowed_subrange_t

Range primitives
range_size_trange_difference_trange_value_t elements_of (C++23)	iterator_tconst_iterator_tsentinel_tconst_sentinel_t (C++23)(C++23)	range_reference_trange_const_reference_trange_rvalue_reference_trange_common_reference_t (C++23)

Range concepts
range borrowed_range    common_range	sized_range viewable_range    view	input_range output_range forward_range	bidirectional_range    random_access_range contiguous_range	approximately_sized_range (C++26) constant_range (C++23)

Views
view_interface	subrange

Range factories
empty_viewviews::empty	single_viewviews::single	basic_istream_viewviews::istream	iota_viewviews::iota	repeat_viewviews::repeat (C++23)(C++23)

Range adaptors
views::all_tviews::all as_rvalue_viewviews::as_rvalue (C++23)(C++23)   filter_viewviews::filter transform_viewviews::transform take_viewviews::take take_while_viewviews::take_while common_viewviews::common views::counted as_input_viewviews::as_input (C++26)(C++26)	ref_view drop_viewviews::drop drop_while_viewviews::drop_while lazy_split_viewviews::lazy_split split_viewviews::split join_viewviews::join join_with_viewviews::join_with (C++23)(C++23)   concat_viewviews::concat (C++26)(C++26) cache_latest_viewviews::cache_latest (C++26)(C++26)	owning_view reverse_viewviews::reverse as_const_viewviews::as_const (C++23)(C++23) elements_viewviews::elements keys_viewviews::keys values_viewviews::values enumerate_viewviews::enumerate (C++23)(C++23) zip_viewviews::zip (C++23)(C++23) zip_transform_viewviews::zip_transform (C++23)(C++23)	adjacent_viewviews::adjacent (C++23)(C++23) views::pairwise (C++23) adjacent_transform_viewviews::adjacent_transform (C++23)(C++23) views::pairwise_transform (C++23) chunk_viewviews::chunk (C++23)(C++23) slide_viewviews::slide (C++23)(C++23) chunk_by_viewviews::chunk_by (C++23)(C++23) stride_viewviews::stride (C++23)(C++23) cartesian_product_viewviews::cartesian_product (C++23)(C++23)

Range generators std::generator (C++23)

Range adaptor closure objects range_adaptor_closure (C++23)

Range adaptor objects

Helper items
copyable-box movable-box (until C++23)  (C++23)	simple-view non-propagating-cache

 

std::ranges::lazy_split_view

Member functions

lazy_split_view::lazy_split_view

lazy_split_view::base

lazy_split_view::begin

lazy_split_view::end

Nested classes

lazy_split_view::outer_iterator

lazy_split_view::outer_iterator::value_type

lazy_split_view::inner_iterator

Deduction guides

 

template< bool Const > struct /*inner_iterator*/;		(since C++20) (exposition only*)

The return type of lazy_split_view::outer_iterator::value_type::begin().

Const matches the template argument of outer_iterator.

Member types

Member	Definition
Base	maybe-const <Const, V> (exposition-only member type*)
iterator_concept	outer_iterator<Const>::iterator_concept, that is std::forward_iterator_tag, if Base models forward_range. std::input_iterator_tag, otherwise.
iterator_category (conditionally present)	Present only if Base models forward_range. std::forward_iterator_tag if std::iterator_traits<ranges::iterator_t<Base>>::iterator_category models std::derived_from<std::forward_iterator_tag>. std::iterator_traits<ranges::iterator_t<Base>>::iterator_category otherwise.
value_type	ranges::range_value_t<Base>
difference_type	ranges::range_difference_t<Base>

Data members

Member	Description
outer_iterator<Const> i_ (private)	an iterator into the underlying view of the parent object lazy_split_view (exposition-only member object*)
bool incremented_ (private)	a flag that indicates whether the operator++ was invoked on this object at least once (exposition-only member object*)

Member functions

(constructor) (C++20)	constructs an iterator (public member function)
base (C++20)	returns the underlying iterator (public member function)
operator* (C++20)	returns the current element (public member function)
operator++operator++(int) (C++20)	advances the iterator (public member function)

Member functions

std::ranges::lazy_split_view::inner_iterator::inner_iterator

/*inner_iterator*/() = default;	(1)	(since C++20)
constexpr explicit /*inner_iterator*/( /*outer_iterator*/<Const> i );	(2)	(since C++20)

1) Value initializes data member i_ via its default member initializer (= /*outer_iterator*/<Const>()).

2) Initializes i_ with std::move(i).

The data member incremented_ is initialized with its default member initializer to false.

std::ranges::lazy_split_view::inner_iterator::base

constexpr const ranges::iterator_t<Base>& base() const & noexcept;	(1)	(since C++20)
constexpr ranges::iterator_t<Base> base() && requires ranges::forward_range<V>;	(2)	(since C++20)

Returns a copy of the underlying iterator.

1) Copy constructs the result from the underlying iterator. Equivalent to return i_./*cur*/();.

2) Move constructs the result from the underlying iterator. Equivalent to return std::move(i_./*cur*/());.

std::ranges::lazy_split_view::inner_iterator::operator*

constexpr decltype(auto) operator*() const;		(since C++20)

Returns the element the underlying iterator points to.

Equivalent to return *i_./*cur*/();.

std::ranges::lazy_split_view::inner_iterator::operator++

constexpr /*inner_iterator*/& operator++();	(1)	(since C++20)
constexpr decltype(auto) operator++(int);	(2)	(since C++20)

1) The function body is equivalent to
incremented_ = true; if constexpr (!ranges::forward_range<Base>) { if constexpr (Pattern::size() == 0) return *this; } ++i_./*cur*/(); return *this;

2) Equivalent to
if constexpr (ranges::forward_range<Base>) { auto tmp = *this; ++*this; return tmp; } else ++*this; // no return statement

Non-member functions

operator== (C++20)	compares the iterators or the iterator and std::default_sentinel (function)
iter_move (C++20)	casts the result of dereferencing the underlying iterator to its associated rvalue reference type (function)
iter_swap (C++20)	swaps the objects pointed to by two underlying iterators (function)

operator==(std::ranges::split_view::inner_iterator)

friend constexpr bool operator==( const /*inner_iterator*/& x, const /*inner_iterator*/& y ) requires forward_range<Base>;	(1)	(since C++20)
friend constexpr bool operator==( const /*inner_iterator*/& x, std::default_sentinel_t );	(2)	(since C++20)

1) Equivalent to return x.i_./*cur*/() == y.i_./*cur*/();.

2) The function body is equivalent to

auto [pcur, pend] = ranges::subrange{x.i_.parent_->pattern_};
auto end = ranges::end(x.i_.parent_->base_);
if constexpr (/*tiny_range*/<Pattern>)
{
    const auto& cur = x.i_./*cur*/();
    if (cur == end)
        return true;
    if (pcur == pend)
        return x.incremented_;
    return *cur == *pcur;
}
else
{
    auto cur = x.i_./*cur*/();
    if (cur == end)
        return true;
    if (pcur == pend)
        return x.incremented_;
    do
    {
        if (*cur != *pcur)
            return false;
        if (++pcur == pend)
            return true;
    }
    while (++cur != end);
    return false;
}

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::inner_iterator is an associated class of the arguments.

iter_move(std::ranges::split_view::inner_iterator)

friend constexpr decltype(auto) iter_move( const /*inner_iterator*/& i ) noexcept(noexcept(ranges::iter_move(i.i_./*cur*/())));		(since C++20)

Equivalent to return ranges::iter_move(i.i_./*cur*/());.

This function is not visible to ordinary unqualified or qualified lookup, and can only be found by argument-dependent lookup when std::ranges::split_view::inner_iterator is an associated class of the arguments.

iter_swap(std::ranges::split_view::inner_iterator)

friend constexpr void iter_swap( const /*inner_iterator*/& x, const /*inner_iterator*/& y ) noexcept(noexcept(ranges::iter_swap(x.i_.current, y.i_.current))) requires std::indirectly_swappable<ranges::iterator_t<Base>>;		(since C++20)

Equivalent to ranges::iter_swap(x.i_./*cur*/(), y.i_./*cur*/()).

This function is not visible to ordinary unqualified or qualified lookup, and can only be found by argument-dependent lookup when std::ranges::split_view::inner_iterator is an associated class of the arguments.

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 3591	C++20	the && overload of base might invalidate outer iterators	constraints added
LWG 3593	C++20	the const& overload of base returns a reference but might not be noexcept	made noexcept