ostreambuf_iterator
class template
<iterator>
template <class charT, class traits=char_traits<charT> >
class ostreambuf_iterator;
Output stream buffer iterator
Ostreambuf iterators are a special output iterator class designed to write successive elements to a stream buffer (streambuf or another basic_streambuf class).
They are constructed from a basic_streambuf object open for writing, to which they become associated.
It is defined with an operation similar to:
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template <class charT=char, class traits=char_traits<charT> >
class ostreambuf_iterator :
public iterator<output_iterator_tag, charT,
typename traits::off_type, charT*, charT&>
{
public:
typedef charT char_type;
typedef traits traits_type;
typedef typename traits::int_type int_type;
typedef basic_streambuf<charT,traits> streambuf_type;
typedef basic_ostream<charT,traits> ostream_type;
ostreambuf_iterator(ostream_type& s) throw(): sbuf_(s.rdbuf()) { }
ostreambuf_iterator(streambuf_type* s) throw(): sbuf_(s) { }
ostreambuf_iterator& operator= (charT c)
{ if (!failed()) last=sbuf_->sputc(c); return *this; }
ostreambuf_iterator& operator*() { return *this; }
ostreambuf_iterator& operator++() { return *this; }
ostreambuf_iterator& operator++(int) { return *this;}
bool failed() const throw() { return last==traits::eof(); }
private:
streambuf_type* sbuf_;
charT last;
};
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Template parameters
- charT
- Character type. This is the first template parameter in the basic_streambuf object.
- traits
- Character traits. This is the second template parameter in basic_streambuf object.
Member functions
- constructor
- ostreambuf_iterator objects are constructed from either a basic_streambuf object or a basic_ostream object.
- operator=
- Writes an element into the stream buffer.
- operator*
- Returns the current value in the stream buffer.
- operator*
- Does nothing. Returns a reference to the object.
- operator++
- Does nothing. Returns a reference to the object.
- failed
- Returns whether a previous writing operation failed (i.e. streambuf::sputc returned traits::eof() in a previous call to operator=).
Example
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// ostreambuf_iterator example
#include <iostream>
#include <iterator>
#include <string>
using namespace std;
int main () {
string mystring ("Some text here...\n");
ostreambuf_iterator<char> out_it (cout); // stdout iterator
copy ( mystring.begin(), mystring.end(), out_it);
return 0;
}
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Possible output:
See also
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