std::ranges...ew::iterator(3)

✨ NAME ✨

Hey bestie 💖 this is the C++ Standard Libary page for std::ranges...ew::iterator(3) — aka std::ranges::basic_istream_view::iterator, the exposition-only iterator that is literally the return type of basic_istream_view::begin. It’s giving “tiny but important,” no cap 👑

✨ Synopsis ✨

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

The return type of basic_istream_view::begin.

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

🧸 Member types 🧸

• 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. Iykyk 👀

🧚 Defect reports 🧚

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

• P2325R3 — applied to C++20; behavior as published: default constructor was provided as iterators must be default_initializable; correct behavior: removed along with the requirement.

---

Source/version/date drop, bestie: http://cppreference.com · 2024.06.10 · page std::ranges...ew::iterator(3) 🎀✨ Byeee, go stream responsibly 💜