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

 

C++

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Standard library

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 to_input_viewviews::to_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/*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.

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	std::forward_iterator_tag, if Base models forward_range, std::input_iterator_tag, otherwise
iterator_category (present only if Base models forward_range)	std::input_iterator_tag
value_type	the value type of the outer_iterator (public member class)
difference_type	ranges::range_difference_t<Base>

Data members

Member	Description
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*)
booltrailing_empty_(private)	a flag that indicates whether an empty trailing subrange (if any) was reached (exposition-only member object*)

Member functions

(constructor)	constructs an iterator (public member function)
operator*	returns the current subrange (public member function)
operator++operator++(int)	advances the iterator (public member function)
cur	returns conditionally a reference to the current_ (if present) or to the *parent_->current_ (exposition-only member function*)

Member functions

std::ranges::lazy_split_view::outer_iterator ::outer_iterator

/*outer_iterator*/()=default;	(1)	(since C++20)
constexprexplicit/*outer_iterator*/( Parent& parent )     requires (!ranges::forward_range<Base>);	(2)	(since C++20)
constexpr/*outer_iterator*/( Parent& parent,                               ranges::iterator_t<Base> current )     requires ranges::forward_range<Base>;	(3)	(since C++20)
constexpr/*outer_iterator*/(/*outer_iterator*/<!Const> i )     requires Const &&std::convertible_to<ranges::iterator_t<V>,                                           ranges::iterator_t<Base>>;	(4)	(since C++20)

1) Value initializes the non-static data members with their default member initializer, that is:

• parent_ = nullptr;,
• current_ = iterator_t<Base>(); (present only if V models forward_range),

2) Initializes parent_ with std::addressof(parent).

3) Initializes parent_ with std::addressof(parent) and current_ with std::move(current).

4) Initializes 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)

1) The function body is equivalent to

constauto end =ranges::end(parent_->base_);if(/*cur*/()== end){ trailing_empty_ =false;return*this;}constauto[pbegin, pend]=ranges::subrange{parent_->pattern_};if(pbegin == pend)++/*cur*/();elseifconstexpr(/*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;

2) Equivalent to

ifconstexpr(ranges::forward_range<Base>){auto tmp =*this;++*this;return tmp;}else{++*this;// no return statement}

std::ranges::lazy_split_view::outer_iterator ::cur ()

constexprauto&/*cur*/()noexcept;	(1)	(since C++20) (exposition only*)
constexprauto&/*cur*/()constnoexcept;	(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.

1,2) Equivalent to

ifconstexpr(ranges::forward_range<V>)return current_;elsereturn*parent->current_;

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)

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

1) Equivalent to return x.current_== y.current_ and x.trailing_empty_== y.trailing_empty_;.

2) Equivalent to return x./*cur*/()==ranges::end(x.parent_->base_) and !x.trailing_empty_;.

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.

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