ostream_iterator writes (using operator<<) successive elements onto the output stream from which it was constructed. If it was constructed with charT* as a constructor argument, this string, called a delimiter string, is written to the stream after every T is written. It is not possible to get a value out of the output iterator. Its only use is as an output iterator in situations like
while (first != last) *result++ = *first++;
ostream_iterator is defined as:
namespace std { template <class T, class charT = char, class traits = char_traits<charT> > class ostream_iterator: public iterator<output_iterator_tag, void, void, void, void> { public: typedef charT char_type; typedef traits traits_type; typedef basic_ostream<charT,traits> ostream_type; ostream_iterator(ostream_type& s); ostream_iterator(ostream_type& s, const charT* delimiter); ostream_iterator(const ostream_iterator<T,charT,traits>& x); ~ostream_iterator(); ostream_iterator<T,charT,traits>& operator=(const T& value); ostream_iterator<T,charT,traits>& operator*(); ostream_iterator<T,charT,traits>& operator++(); ostream_iterator<T,charT,traits>& operator++(int); private: basic_ostream<charT,traits>* out_stream; // exposition only const charT* delim; // exposition only }; }
ostream_iterator(ostream_type& s);
Effects: Initializes out_stream with &s and delim with null.
ostream_iterator(ostream_type& s, const charT* delimiter);
Effects: Initializes out_stream with &s and delim with delimiter.
ostream_iterator(const ostream_iterator& x);
Effects: Constructs a copy of x.
Effects: The iterator is destroyed.
ostream_iterator& operator=(const T& value);
Effects:
*out_stream << value; if(delim != 0) *out_stream << delim; return (*this);
ostream_iterator& operator*();
Returns: *this.
ostream_iterator& operator++();
ostream_iterator& operator++(int);
Returns: *this.