23 Iterators library [iterators]

23.6 Stream iterators [stream.iterators]

23.6.5 Class template ostreambuf_­iterator [ostreambuf.iterator] General [ostreambuf.iterator.general]

The class template ostreambuf_­iterator writes successive characters onto the output stream from which it was constructed.
namespace std { template<class charT, class traits = char_traits<charT>> class ostreambuf_iterator { public: using iterator_category = output_iterator_tag; using value_type = void; using difference_type = ptrdiff_t; using pointer = void; using reference = void; using char_type = charT; using traits_type = traits; using streambuf_type = basic_streambuf<charT,traits>; using ostream_type = basic_ostream<charT,traits>; constexpr ostreambuf_iterator() noexcept = default; ostreambuf_iterator(ostream_type& s) noexcept; ostreambuf_iterator(streambuf_type* s) noexcept; ostreambuf_iterator& operator=(charT c); ostreambuf_iterator& operator*(); ostreambuf_iterator& operator++(); ostreambuf_iterator& operator++(int); bool failed() const noexcept; private: streambuf_type* sbuf_ = nullptr; // exposition only }; } Constructors [ostreambuf.iter.cons]

ostreambuf_iterator(ostream_type& s) noexcept;
Preconditions: s.rdbuf() is not a null pointer.
Effects: Initializes sbuf_­ with s.rdbuf().
ostreambuf_iterator(streambuf_type* s) noexcept;
Preconditions: s is not a null pointer.
Effects: Initializes sbuf_­ with s. Operations [ostreambuf.iter.ops]

ostreambuf_iterator& operator=(charT c);
Effects: If failed() yields false, calls sbuf_­->sputc(c); otherwise has no effect.
Returns: *this.
ostreambuf_iterator& operator*();
Returns: *this.
ostreambuf_iterator& operator++(); ostreambuf_iterator& operator++(int);
Returns: *this.
bool failed() const noexcept;
Returns: true if in any prior use of member operator=, the call to sbuf_­->sputc() returned traits​::​eof(); or false otherwise.