namespace std { template <class charT, class traits = char_traits<charT>, class Allocator = allocator<charT> > class basic_ostringstream : public basic_ostream<charT,traits> { public: // types: typedef charT char_type; typedef typename traits::int_type int_type; typedef typename traits::pos_type pos_type; typedef typename traits::off_type off_type; typedef traits traits_type; typedef Allocator allocator_type; // [ostringstream.cons] Constructors/destructor: explicit basic_ostringstream(ios_base::openmode which = ios_base::out); explicit basic_ostringstream( const basic_string<charT,traits,Allocator>& str, ios_base::openmode which = ios_base::out); basic_ostringstream(const basic_ostringstream& rhs) = delete; basic_ostringstream(basic_ostringstream&& rhs); // [ostringstream.assign] Assign/swap: basic_ostringstream& operator=(const basic_ostringstream& rhs) = delete; basic_ostringstream& operator=(basic_ostringstream&& rhs); void swap(basic_ostringstream& rhs); // [ostringstream.members] Members: basic_stringbuf<charT,traits,Allocator>* rdbuf() const; basic_string<charT,traits,Allocator> str() const; void str(const basic_string<charT,traits,Allocator>& s); private: basic_stringbuf<charT,traits,Allocator> sb; // exposition only }; template <class charT, class traits, class Allocator> void swap(basic_ostringstream<charT, traits, Allocator>& x, basic_ostringstream<charT, traits, Allocator>& y); }
The class basic_ostringstream<charT, traits, Allocator> supports writing objects of class basic_string<charT, traits, Allocator>. It uses a basic_stringbuf object to control the associated storage. For the sake of exposition, the maintained data is presented here as:
sb, the stringbuf object.
explicit basic_ostringstream(ios_base::openmode which = ios_base::out);
Effects: Constructs an object of class basic_ostringstream, initializing the base class with basic_ostream(&sb) and initializing sb with basic_stringbuf<charT, traits, Allocator>(which | ios_base::out)) ([stringbuf.cons]).
explicit basic_ostringstream(
const basic_string<charT,traits,Allocator>& str,
ios_base::openmode which = ios_base::out);
Effects: Constructs an object of class basic_ostringstream<charT, traits>, initializing the base class with basic_ostream(&sb) and initializing sb with basic_stringbuf<charT, traits, Allocator>(str, which | ios_base::out)) ([stringbuf.cons]).
basic_ostringstream(basic_ostringstream&& rhs);
Effects: Move constructs from the rvalue rhs. This is accomplished by move constructing the base class, and the contained basic_stringbuf. Next basic_ostream<charT,traits>::set_rdbuf(&sb) is called to install the contained basic_stringbuf.
basic_ostringstream& operator=(basic_ostringstream&& rhs);
Effects: Move assigns the base and members of *this from the base and corresponding members of rhs.
Returns: *this.
void swap(basic_ostringstream& rhs);
Effects: Exchanges the state of *this and rhs by calling basic_ostream<charT,traits>::swap(rhs) and sb.swap(rhs.sb).
template <class charT, class traits, class Allocator>
void swap(basic_ostringstream<charT, traits, Allocator>& x,
basic_ostringstream<charT, traits, Allocator>& y);
Effects: x.swap(y).
basic_stringbuf<charT,traits,Allocator>* rdbuf() const;
Returns: const_cast<basic_stringbuf<charT,traits,Allocator>*>(&sb).
basic_string<charT,traits,Allocator> str() const;
Returns: rdbuf()->str().
void str(const basic_string<charT,traits,Allocator>& s);
Effects: Calls rdbuf()->str(s).