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std::ranges::basic_istream_view::iterator

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Ranges library
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(C++23)
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std::ranges::basic_istream_view
Member functions
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.

Contents

[edit] 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

[edit] 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.

[edit] 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.

[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
P2325R3 C++20 default constructor was provided as C++20 iterators
must be default_initializable
removed along with the requirement