W3cubDocs

/C++

std::ranges::basic_istream_view::iterator 

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

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

© cppreference.com
Licensed under the Creative Commons Attribution-ShareAlike Unported License v3.0.
https://en.cppreference.com/w/cpp/ranges/basic_istream_view/iterator