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                       Standard C++ Library
             Copyright 1998, Rogue Wave Software, Inc.


NAME
     ostream_iterator

      - Stream iterators allow for use of iterators with ostreams
     and  istreams.  They  allow  generic  algorithms  to be used
     directly on streams.



SYNOPSIS
     #include <ostream>
     template <class T, class charT,
              class traits = char_traits<charT> >
     class ostream_iterator
      : public iterator<output_iterator_tag,void,void>;



DESCRIPTION
     Stream iterators use the  standard  iterator  interface  for
     input and output streams.

     The class ostream_iterator  writes  elements  to  an  output
     stream.  If you use the constructor that has a second char *
     argument, then that string is written  after  every  element
     (the  string  must  be  null-terminated).  Since  an ostream
     iterator is an output iterator, it is not possible to get an
     element out of the iterator. You can only assign to it.



INTERFACE
     template <class T, class charT,
              class traits = char_traits<charT> >
     class ostream_iterator
        : public iterator<output_iterator_tag,void,void>
     {
     public:

      typedef T value_type;
      typedef charT char_type;
      typedef traits traits_type;
      typedef basic_ostream<charT,traits> ostream_type;


        ostream_iterator(ostream&);
        ostream_iterator (ostream&, const char*);
        ostream_iterator (const
                ostream_iterator<T,charT,char_traits<charT> >&);
         ~ostream_itertor ();
        ostream_iterator<T,charT,char_traits<charT> >&
             operator=(const T&);
        ostream_iterator<T,charT,char_traits<charT> >&
             operator* () const;
        ostream_iterator<T,charT,char_traits<charT> >&
             operator++ ();
        ostream_iterator<T,charT,char_traits<charT> >
             operator++ (int);
      };



TYPES
     value_type;


        Type of value to stream in.



     char_type;


        Type of character the stream is built on.



     traits_type;


        Traits used to build the stream.



     ostream_type;


        Type of stream this iterator is constructed on.



CONSTRUCTORS
     ostream_iterator (ostream& s);

        Constructs an_ostream_iterator on the given stream.



     ostream_iterator (ostream& s, const char* delimiter);


        Constructs an_ostream_iterator on the given  stream.  The
        null terminated string delimiter is written to the stream
        after every element.



     ostream_iterator (const ostream_iterator<T>& x);


         Copy constructor.



DESTRUCTORS
     ~ostream_iterator ();


        Destroys an object of class ostream_iterator.



OPERATORS
     const T& <br>operator= (const T& value);


         Shift the value T onto the output stream.



     const T& ostream_iterator<T>&
     operator* ();
     ostream_iterator<T>&
     operator++();
     ostream_iterator<T>
     operator++ (int);


        These operators do nothing. They simply allow the  itera-
        tor to be used in common constructs.


EXAMPLE
      #include <iterator>
      #include <numeric>
      #include <deque>
      #include <iostream>
     using namespace std;

     int main ()
      {
        //
        // Initialize a vector using an array.
        //
       int arr[4] = { 3,4,7,8 };
       int total=0;
       deque<int> d(arr+0, arr+4);
        //
        // stream the whole vector and a sum to cout
        //
       copy(d.begin(),d.end()-1,
             ostream_iterator<int,char>(cout," + "));
       cout << *(d.end()-1) << " = " <<
            accumulate(d.begin(),d.end(),total) << endl;
       return 0;
      }



WARNINGS
     If your compiler does not support default  template  parame-
     ters,  then you always need to supply the Allocator template
     argument. For instance, you need to write:

     deque<int, allocator<int> >

     instead of:

     deque<int>

     If your compiler does not support namespaces,  then  you  do
     not need the using declaration for std.



SEE ALSO
     istream_iterator, Iterators

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