std::ranges::basic_istream_view::iterator

 

C++

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Named requirements

Feature test macros (C++20)

Language support library

Concepts library (C++20)

Metaprogramming library (C++11)

Diagnostics library

General utilities library

Strings library

Containers library

Iterators library

Ranges library (C++20)

Algorithms library

Numerics library

Localizations library

Input/output library

Filesystem library (C++17)

Regular expressions library (C++11)

Concurrency support library (C++11)

Technical specifications

Symbols index

External libraries

 

Ranges library

Range access
begin cbegin end cend	rbegin crbegin rend crend	size ssize data cdata	empty
Range conversions
to (C++23)
Range primitives
range_size_trange_difference_t range_value_t	range_reference_trange_const_reference_trange_rvalue_reference_t   (C++23)	iterator_tconst_iterator_tsentinel_t (C++23)
Dangling iterator handling
dangling	borrowed_iterator_t	borrowed_subrange_t
Range concepts
range borrowed_range    sized_range constant_range (C++23)	common_range view viewable_range	input_range output_range forward_range	bidirectional_range random_access_range contiguous_range
Views
view_interface	subrange
Factories
empty_viewviews::empty iota_viewviews::iota	single_viewviews::single basic_istream_viewviews::istream	repeat_viewviews::repeat (C++23)(C++23)
Adaptors
ref_view views::all_tviews::all common_viewviews::common owning_view views::counted reverse_viewviews::reverse zip_viewviews::zip (C++23)(C++23) as_const_viewviews::as_const (C++23)(C++23) as_rvalue_viewviews::as_rvalue (C++23)(C++23)	take_viewviews::take take_while_viewviews::take_while drop_viewviews::drop drop_while_viewviews::drop_while zip_transform_viewviews::zip_transform (C++23)(C++23) adjacent_transform_viewviews::adjacent_transform (C++23)(C++23)   cartesian_product_viewviews::cartesian_product (C++23)(C++23)	elements_viewviews::elements keys_viewviews::keys values_viewviews::values transform_viewviews::transform adjacent_viewviews::adjacent (C++23)(C++23) slide_viewviews::slide (C++23)(C++23) stride_viewviews::stride (C++23)(C++23)	filter_viewviews::filter join_viewviews::join split_viewviews::split lazy_split_viewviews::lazy_split join_with_viewviews::join_with (C++23)(C++23) chunk_viewviews::chunk (C++23)(C++23) chunk_by_viewviews::chunk_by (C++23)(C++23)
Range adaptor objects
Range adaptor closure objects
Helper items
copyable-box	simple-view

 

std::ranges::basic_istream_view

Member functions

basic_istream_view::basic_istream_view (C++20)

basic_istream_view::begin (C++20)

basic_istream_view::end (C++20)

Iterator

basic_istream_view::iterator::iterator (C++20)

basic_istream_view::iterator::operator= (C++20)

basic_istream_view::iterator::operator++ (C++20)

basic_istream_view::iterator::operator* (C++20)

operator==(basic_istream_view::iterator) (C++20)

 

struct /*iterator*/;		(since C++20)

The return type of basic_istream_view::begin. The name /*iterator*/ shown here is exposition only.

/*iterator*/ is an input_iterator, but does not satisfy LegacyInputIterator, and thus does not work with pre-C++20 algorithms.

Member types

Member type	Definition
iterator_concept(C++20)	std::input_iterator_tag
difference_type(C++20)	std::ptrdiff_t
value_type(C++20)	Val

Member functions

(constructor) (C++20)	constructs an iterator (public member function)
operator= (C++20)	the copy assignment operator is deleted; /*iterator*/ is move-only (public member function)
operator++ (C++20)	advances the iterator (public member function)
operator* (C++20)	returns the current element (public member function)

std::ranges::basic_istream_view::iterator::iterator

constexpr explicit /*iterator*/( basic_istream_view& parent );	(1)	(since C++20)
/*iterator*/( const /*iterator*/& ) = delete;	(2)	(since C++20)
/*iterator*/( /*iterator*/&& ) = default;	(3)	(since C++20)

1) Constructs an iterator from the parent basic_istream_view.

2) The copy constructor is deleted. The iterator is not copyable.

3) The move constructor is defaulted. The iterator is movable.

std::ranges::basic_istream_view::iterator::operator=

/*iterator*/& operator=( const /*iterator*/& ) = delete;	(1)	(since C++20)
/*iterator*/& operator=( /*iterator*/&& ) = default;	(2)	(since C++20)

1) The copy assignment operator is deleted. The iterator is not copyable.

2) The move assignment operator is defaulted. The iterator is movable.

std::ranges::basic_istream_view::iterator::operator++

/*iterator*/& operator++();	(1)	(since C++20)
void operator++(int);	(2)	(since C++20)

Reads a value from the underlying stream and stores it into the parent basic_istream_view.

Return value

1) *this

2) (none)

std::ranges::basic_istream_view::iterator::operator*

Val& operator*() const;		(since C++20)

Returns a reference to the stored value.

Non-member functions

operator== (C++20)

compares with a std::default_sentinel_t (public member function)

operator==(std::ranges::basic_istream_view::iterator, std::default_sentinel)

friend bool operator==( const /*iterator*/& x, std::default_sentinel_t );		(since C++20)

Compares an iterator with std::default_sentinel_t.

Returns true if *this does not have a parent basic_istream_view, or if an error has occurred on the underlying stream.

This function is not visible to ordinary unqualified or qualified lookup, and can only be found by argument-dependent lookup when std::ranges::basic_istream_view::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
P2325R3	C++20	default constructor was provided as C++20 iterators must be default_initializable	removed along with the requirement