// -*- C++ -*-
//===--------------------------- sstream ----------------------------------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//

#ifndef _LIBCPP_SSTREAM
#define _LIBCPP_SSTREAM

/*
    sstream synopsis

template <class charT, class traits = char_traits<charT>, class Allocator = allocator<charT> >
class basic_stringbuf
    : public basic_streambuf<charT, traits>
{
public:
    typedef charT                          char_type;
    typedef traits                         traits_type;
    typedef typename traits_type::int_type int_type;
    typedef typename traits_type::pos_type pos_type;
    typedef typename traits_type::off_type off_type;
    typedef Allocator                      allocator_type;

    // 27.8.1.1 Constructors:
    explicit basic_stringbuf(ios_base::openmode which = ios_base::in | ios_base::out);
    explicit basic_stringbuf(const basic_string<char_type, traits_type, allocator_type>& str,
                             ios_base::openmode which = ios_base::in | ios_base::out);
    basic_stringbuf(basic_stringbuf&& rhs);

    // 27.8.1.2 Assign and swap:
    basic_stringbuf& operator=(basic_stringbuf&& rhs);
    void swap(basic_stringbuf& rhs);

    // 27.8.1.3 Get and set:
    basic_string<char_type, traits_type, allocator_type> str() const;
    void str(const basic_string<char_type, traits_type, allocator_type>& s);

protected:
    // 27.8.1.4 Overridden virtual functions:
    virtual int_type underflow();
    virtual int_type pbackfail(int_type c = traits_type::eof());
    virtual int_type overflow (int_type c = traits_type::eof());
    virtual basic_streambuf<char_type, traits_type>* setbuf(char_type*, streamsize);
    virtual pos_type seekoff(off_type off, ios_base::seekdir way,
                             ios_base::openmode which = ios_base::in | ios_base::out);
    virtual pos_type seekpos(pos_type sp,
                             ios_base::openmode which = ios_base::in | ios_base::out);
};

template <class charT, class traits, class Allocator>
  void swap(basic_stringbuf<charT, traits, Allocator>& x,
            basic_stringbuf<charT, traits, Allocator>& y);

typedef basic_stringbuf<char>    stringbuf;
typedef basic_stringbuf<wchar_t> wstringbuf;

template <class charT, class traits = char_traits<charT>, class Allocator = allocator<charT> >
class basic_istringstream
    : public basic_istream<charT, traits>
{
public:
    typedef charT                          char_type;
    typedef traits                         traits_type;
    typedef typename traits_type::int_type int_type;
    typedef typename traits_type::pos_type pos_type;
    typedef typename traits_type::off_type off_type;
    typedef Allocator                      allocator_type;

    // 27.8.2.1 Constructors:
    explicit basic_istringstream(ios_base::openmode which = ios_base::in);
    explicit basic_istringstream(const basic_string<char_type, traits_type,allocator_type>& str,
                                 ios_base::openmode which = ios_base::in);
    basic_istringstream(basic_istringstream&& rhs);

    // 27.8.2.2 Assign and swap:
    basic_istringstream& operator=(basic_istringstream&& rhs);
    void swap(basic_istringstream& rhs);

    // 27.8.2.3 Members:
    basic_stringbuf<char_type, traits_type, allocator_type>* rdbuf() const;
    basic_string<char_type, traits_type, allocator_type> str() const;
    void str(const basic_string<char_type, traits_type, allocator_type>& s);
};

template <class charT, class traits, class Allocator>
  void swap(basic_istringstream<charT, traits, Allocator>& x,
            basic_istringstream<charT, traits, Allocator>& y);

typedef basic_istringstream<char>    istringstream;
typedef basic_istringstream<wchar_t> wistringstream;

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 traits                         traits_type;
    typedef typename traits_type::int_type int_type;
    typedef typename traits_type::pos_type pos_type;
    typedef typename traits_type::off_type off_type;
    typedef Allocator                      allocator_type;

    // 27.8.3.1 Constructors/destructor:
    explicit basic_ostringstream(ios_base::openmode which = ios_base::out);
    explicit basic_ostringstream(const basic_string<char_type, traits_type, allocator_type>& str,
                                 ios_base::openmode which = ios_base::out);
    basic_ostringstream(basic_ostringstream&& rhs);

    // 27.8.3.2 Assign/swap:
    basic_ostringstream& operator=(basic_ostringstream&& rhs);
    void swap(basic_ostringstream& rhs);

    // 27.8.3.3 Members:
    basic_stringbuf<char_type, traits_type, allocator_type>* rdbuf() const;
    basic_string<char_type, traits_type, allocator_type> str() const;
    void str(const basic_string<char_type, traits_type, allocator_type>& s);
};

template <class charT, class traits, class Allocator>
  void swap(basic_ostringstream<charT, traits, Allocator>& x,
            basic_ostringstream<charT, traits, Allocator>& y);

typedef basic_ostringstream<char>    ostringstream;
typedef basic_ostringstream<wchar_t> wostringstream;

template <class charT, class traits = char_traits<charT>, class Allocator = allocator<charT> >
class basic_stringstream
    : public basic_iostream<charT, traits>
{
public:
    // types:
    typedef charT                          char_type;
    typedef traits                         traits_type;
    typedef typename traits_type::int_type int_type;
    typedef typename traits_type::pos_type pos_type;
    typedef typename traits_type::off_type off_type;
    typedef Allocator                      allocator_type;

    // constructors/destructor
    explicit basic_stringstream(ios_base::openmode which = ios_base::out|ios_base::in);
    explicit basic_stringstream(const basic_string<char_type, traits_type, allocator_type>& str,
                                ios_base::openmode which = ios_base::out|ios_base::in);
    basic_stringstream(basic_stringstream&& rhs);

    // 27.8.5.1 Assign/swap:
    basic_stringstream& operator=(basic_stringstream&& rhs);
    void swap(basic_stringstream& rhs);

    // Members:
    basic_stringbuf<char_type, traits_type, allocator_type>* rdbuf() const;
    basic_string<char_type, traits_type, allocator_type> str() const;
    void str(const basic_string<char_type, traits_type, allocator_type>& str);
};

template <class charT, class traits, class Allocator>
  void swap(basic_stringstream<charT, traits, Allocator>& x,
            basic_stringstream<charT, traits, Allocator>& y);

typedef basic_stringstream<char>    stringstream;
typedef basic_stringstream<wchar_t> wstringstream;

}  // std

*/

#include <__config>
#include <ostream>
#include <istream>
#include <string>

#pragma GCC system_header

_LIBCPP_BEGIN_NAMESPACE_STD

// basic_stringbuf

template <class _CharT, class _Traits, class _Allocator>
class basic_stringbuf
    : public basic_streambuf<_CharT, _Traits>
{
public:
    typedef _CharT                         char_type;
    typedef _Traits                        traits_type;
    typedef typename traits_type::int_type int_type;
    typedef typename traits_type::pos_type pos_type;
    typedef typename traits_type::off_type off_type;
    typedef _Allocator                     allocator_type;

    typedef basic_string<char_type, traits_type, allocator_type> string_type;

private:

    string_type __str_;
    mutable char_type* __hm_;
    ios_base::openmode __mode_;

public:
    // 27.8.1.1 Constructors:
    explicit basic_stringbuf(ios_base::openmode __wch = ios_base::in | ios_base::out);
    explicit basic_stringbuf(const string_type& __s,
                             ios_base::openmode __wch = ios_base::in | ios_base::out);
#ifdef _LIBCPP_MOVE
    basic_stringbuf(basic_stringbuf&& __rhs);
#endif

    // 27.8.1.2 Assign and swap:
#ifdef _LIBCPP_MOVE
    basic_stringbuf& operator=(basic_stringbuf&& __rhs);
#endif
    void swap(basic_stringbuf& __rhs);

    // 27.8.1.3 Get and set:
    string_type str() const;
    void str(const string_type& __s);

protected:
    // 27.8.1.4 Overridden virtual functions:
    virtual int_type underflow();
    virtual int_type pbackfail(int_type __c = traits_type::eof());
    virtual int_type overflow (int_type __c = traits_type::eof());
    virtual pos_type seekoff(off_type __off, ios_base::seekdir __way,
                             ios_base::openmode __wch = ios_base::in | ios_base::out);
    virtual pos_type seekpos(pos_type __sp,
                             ios_base::openmode __wch = ios_base::in | ios_base::out);
};

template <class _CharT, class _Traits, class _Allocator>
inline _LIBCPP_INLINE_VISIBILITY
basic_stringbuf<_CharT, _Traits, _Allocator>::basic_stringbuf(ios_base::openmode __wch)
    : __hm_(0),
      __mode_(__wch)
{
    str(string_type());
}

template <class _CharT, class _Traits, class _Allocator>
inline _LIBCPP_INLINE_VISIBILITY
basic_stringbuf<_CharT, _Traits, _Allocator>::basic_stringbuf(const string_type& __s,
                             ios_base::openmode __wch)
    : __hm_(0),
      __mode_(__wch)
{
    str(__s);
}

#ifdef _LIBCPP_MOVE

template <class _CharT, class _Traits, class _Allocator>
basic_stringbuf<_CharT, _Traits, _Allocator>::basic_stringbuf(basic_stringbuf&& __rhs)
    : __mode_(__rhs.__mode_)
{
    ptrdiff_t __ninp = __rhs.gptr()  - __rhs.eback();
    ptrdiff_t __einp = __rhs.egptr() - __rhs.eback();
    ptrdiff_t __nout = __rhs.pptr()  - __rhs.pbase();
    ptrdiff_t __eout = __rhs.epptr() - __rhs.pbase();
    ptrdiff_t __hm   = __rhs.__hm_   - __rhs.pbase();
    __str_ = _STD::move(__rhs.__str_);
    char_type* __p = const_cast<char_type*>(__str_.data());
    this->setg(__p, __p + __ninp, __p + __einp);
    this->setp(__p, __p + __eout);
    this->pbump(__nout);
    __hm_ = __p + __hm;
    __p = const_cast<char_type*>(__rhs.__str_.data());
    __rhs.setg(__p, __p, __p);
    __rhs.setp(__p, __p);
    __rhs.__hm_ = __p;
    this->pubimbue(__rhs.getloc());
}

template <class _CharT, class _Traits, class _Allocator>
basic_stringbuf<_CharT, _Traits, _Allocator>&
basic_stringbuf<_CharT, _Traits, _Allocator>::operator=(basic_stringbuf&& __rhs)
{
    ptrdiff_t __ninp = __rhs.gptr()  - __rhs.eback();
    ptrdiff_t __einp = __rhs.egptr() - __rhs.eback();
    ptrdiff_t __nout = __rhs.pptr()  - __rhs.pbase();
    ptrdiff_t __eout = __rhs.epptr() - __rhs.pbase();
    ptrdiff_t __hm   = __rhs.__hm_   - __rhs.pbase();
    __mode_ = __rhs.__mode_;
    __str_ = _STD::move(__rhs.__str_);
    char_type* __p = const_cast<char_type*>(__str_.data());
    this->setg(__p, __p + __ninp, __p + __einp);
    this->setp(__p, __p + __eout);
    this->pbump(__nout);
    __hm_ = __p + __hm;
    __p = const_cast<char_type*>(__rhs.__str_.data());
    __rhs.setg(__p, __p, __p);
    __rhs.setp(__p, __p);
    __rhs.__hm_ = __p;
    this->pubimbue(__rhs.getloc());
    return *this;
}

#endif

template <class _CharT, class _Traits, class _Allocator>
void
basic_stringbuf<_CharT, _Traits, _Allocator>::swap(basic_stringbuf& __rhs)
{
    ptrdiff_t __rninp = __rhs.gptr()  - __rhs.eback();
    ptrdiff_t __reinp = __rhs.egptr() - __rhs.eback();
    ptrdiff_t __rnout = __rhs.pptr()  - __rhs.pbase();
    ptrdiff_t __reout = __rhs.epptr() - __rhs.pbase();
    ptrdiff_t __rhm   = __rhs.__hm_   - __rhs.pbase();
    ptrdiff_t __lninp = this->gptr()  - this->eback();
    ptrdiff_t __leinp = this->egptr() - this->eback();
    ptrdiff_t __lnout = this->pptr()  - this->pbase();
    ptrdiff_t __leout = this->epptr() - this->pbase();
    ptrdiff_t __lhm   = this->__hm_   - this->pbase();
    _STD::swap(__mode_, __rhs.__mode_);
    __str_.swap(__rhs.__str_);
    char_type* __p = const_cast<char_type*>(__str_.data());
    this->setg(__p, __p + __rninp, __p + __reinp);
    this->setp(__p, __p + __reout);
    this->pbump(__rnout);
    __hm_ = __p + __rhm;
    __p = const_cast<char_type*>(__rhs.__str_.data());
    __rhs.setg(__p, __p + __lninp, __p + __leinp);
    __rhs.setp(__p, __p + __leout);
    __rhs.pbump(__lnout);
    __rhs.__hm_ = __p + __lhm;
    locale __tl = __rhs.getloc();
    __rhs.pubimbue(this->getloc());
    this->pubimbue(__tl);
}

template <class _CharT, class _Traits, class _Allocator>
inline _LIBCPP_INLINE_VISIBILITY
void
swap(basic_stringbuf<_CharT, _Traits, _Allocator>& __x,
     basic_stringbuf<_CharT, _Traits, _Allocator>& __y)
{
    __x.swap(__y);
}

template <class _CharT, class _Traits, class _Allocator>
basic_string<_CharT, _Traits, _Allocator>
basic_stringbuf<_CharT, _Traits, _Allocator>::str() const
{
    if (__mode_ & ios_base::out)
    {
        if (__hm_ < this->pptr())
            __hm_ = this->pptr();
        return string_type(this->pbase(), __hm_, __str_.get_allocator());
    }
    else if (__mode_ & ios_base::in)
        return string_type(this->eback(), this->egptr(), __str_.get_allocator());
    return string_type(__str_.get_allocator());
}

template <class _CharT, class _Traits, class _Allocator>
void
basic_stringbuf<_CharT, _Traits, _Allocator>::str(const string_type& __s)
{
    __str_ = __s;
    __hm_ = 0;
    if (__mode_ & ios_base::in)
    {
        __hm_ = const_cast<char_type*>(__str_.data()) + __str_.size();
        this->setg(const_cast<char_type*>(__str_.data()),
                   const_cast<char_type*>(__str_.data()),
                   __hm_);
    }
    if (__mode_ & ios_base::out)
    {
        typename string_type::size_type __sz = __str_.size();
        __hm_ = const_cast<char_type*>(__str_.data()) + __sz;
        __str_.resize(__str_.capacity());
        this->setp(const_cast<char_type*>(__str_.data()),
                   const_cast<char_type*>(__str_.data()) + __str_.size());
        if (__mode_ & (ios_base::app | ios_base::ate))
            this->pbump(__sz);
    }
}

template <class _CharT, class _Traits, class _Allocator>
typename basic_stringbuf<_CharT, _Traits, _Allocator>::int_type
basic_stringbuf<_CharT, _Traits, _Allocator>::underflow()
{
    if (__hm_ < this->pptr())
        __hm_ = this->pptr();
    if (__mode_ & ios_base::in)
    {
        if (this->egptr() < __hm_)
            this->setg(this->eback(), this->gptr(), __hm_);
        if (this->gptr() < this->egptr())
            return traits_type::to_int_type(*this->gptr());
    }
    return traits_type::eof();
}

template <class _CharT, class _Traits, class _Allocator>
typename basic_stringbuf<_CharT, _Traits, _Allocator>::int_type
basic_stringbuf<_CharT, _Traits, _Allocator>::pbackfail(int_type __c)
{
    if (__hm_ < this->pptr())
        __hm_ = this->pptr();
    if (this->eback() < this->gptr())
    {
        if (traits_type::eq_int_type(__c, traits_type::eof()))
        {
            this->setg(this->eback(), this->gptr()-1, __hm_);
            return traits_type::not_eof(__c);
        }
        if ((__mode_ & ios_base::out) ||
            traits_type::eq(traits_type::to_char_type(__c), this->gptr()[-1]))
        {
            this->setg(this->eback(), this->gptr()-1, __hm_);
            *this->gptr() = traits_type::to_char_type(__c);
            return __c;
        }
    }
    return traits_type::eof();
}

template <class _CharT, class _Traits, class _Allocator>
typename basic_stringbuf<_CharT, _Traits, _Allocator>::int_type
basic_stringbuf<_CharT, _Traits, _Allocator>::overflow(int_type __c)
{
    if (!traits_type::eq_int_type(__c, traits_type::eof()))
    {
        ptrdiff_t __ninp = this->gptr()  - this->eback();
        if (this->pptr() == this->epptr())
        {
            if (!(__mode_ & ios_base::out))
                return traits_type::eof();
#ifndef _LIBCPP_NO_EXCEPTIONS
            try
            {
#endif
                ptrdiff_t __nout = this->pptr()  - this->pbase();
                ptrdiff_t __hm = __hm_ - this->pbase();
                __str_.push_back(char_type());
                __str_.resize(__str_.capacity());
                char_type* __p = const_cast<char_type*>(__str_.data());
                this->setp(__p, __p + __str_.size());
                this->pbump(__nout);
                __hm_ = this->pbase() + __hm;
#ifndef _LIBCPP_NO_EXCEPTIONS
            }
            catch (...)
            {
                return traits_type::eof();
            }
#endif
        }
        __hm_ = max(this->pptr() + 1, __hm_);
        if (__mode_ & ios_base::in)
        {
            char_type* __p = const_cast<char_type*>(__str_.data());
            this->setg(__p, __p + __ninp, __hm_);
        }
        return this->sputc(__c);
    }
    return traits_type::not_eof(__c);
}

template <class _CharT, class _Traits, class _Allocator>
typename basic_stringbuf<_CharT, _Traits, _Allocator>::pos_type
basic_stringbuf<_CharT, _Traits, _Allocator>::seekoff(off_type __off,
                                                      ios_base::seekdir __way,
                                                      ios_base::openmode __wch)
{
    if (__hm_ < this->pptr())
        __hm_ = this->pptr();
    if ((__wch & (ios_base::in | ios_base::out)) == 0)
        return pos_type(-1);
    if ((__wch & (ios_base::in | ios_base::out)) == (ios_base::in | ios_base::out)
        && __way == ios_base::cur)
        return pos_type(-1);
    off_type __noff;
    switch (__way)
    {
    case ios_base::beg:
        __noff = 0;
        break;
    case ios_base::cur:
        if (__wch & ios_base::in)
            __noff = this->gptr() - this->eback();
        else
            __noff = this->pptr() - this->pbase();
        break;
    case ios_base::end:
        __noff = __hm_ - __str_.data();
        break;
    default:
        return pos_type(-1);
    }
    __noff += __off;
    if (__noff < 0 || __hm_ - __str_.data() < __noff)
        return pos_type(-1);
    if (__noff != 0)
    {
        if ((__wch & ios_base::in) && this->gptr() == 0)
            return pos_type(-1);
        if ((__wch & ios_base::out) && this->pptr() == 0)
            return pos_type(-1);
    }
    if (__wch & ios_base::in)
        this->setg(this->eback(), this->eback() + __noff, __hm_);
    if (__wch & ios_base::out)
    {
        this->setp(this->pbase(), this->epptr());
        this->pbump(__noff);
    }
    return pos_type(__noff);
}

template <class _CharT, class _Traits, class _Allocator>
inline _LIBCPP_INLINE_VISIBILITY
typename basic_stringbuf<_CharT, _Traits, _Allocator>::pos_type
basic_stringbuf<_CharT, _Traits, _Allocator>::seekpos(pos_type __sp,
                                                      ios_base::openmode __wch)
{
    return seekoff(__sp, ios_base::beg, __wch);
}

// basic_istringstream

template <class _CharT, class _Traits, class _Allocator>
class basic_istringstream
    : public basic_istream<_CharT, _Traits>
{
public:
    typedef _CharT                         char_type;
    typedef _Traits                        traits_type;
    typedef typename traits_type::int_type int_type;
    typedef typename traits_type::pos_type pos_type;
    typedef typename traits_type::off_type off_type;
    typedef _Allocator                     allocator_type;

    typedef basic_string<char_type, traits_type, allocator_type> string_type;

private:
    basic_stringbuf<char_type, traits_type, allocator_type> __sb_;

public:
    // 27.8.2.1 Constructors:
    explicit basic_istringstream(ios_base::openmode __wch = ios_base::in);
    explicit basic_istringstream(const string_type& __s,
                                 ios_base::openmode __wch = ios_base::in);
#ifdef _LIBCPP_MOVE
    basic_istringstream(basic_istringstream&& __rhs);

    // 27.8.2.2 Assign and swap:
    basic_istringstream& operator=(basic_istringstream&& __rhs);
#endif
    void swap(basic_istringstream& __rhs);

    // 27.8.2.3 Members:
    basic_stringbuf<char_type, traits_type, allocator_type>* rdbuf() const;
    string_type str() const;
    void str(const string_type& __s);
};

template <class _CharT, class _Traits, class _Allocator>
inline _LIBCPP_INLINE_VISIBILITY
basic_istringstream<_CharT, _Traits, _Allocator>::basic_istringstream(ios_base::openmode __wch)
    : basic_istream<_CharT, _Traits>(&__sb_),
      __sb_(__wch | ios_base::in)
{
}

template <class _CharT, class _Traits, class _Allocator>
inline _LIBCPP_INLINE_VISIBILITY
basic_istringstream<_CharT, _Traits, _Allocator>::basic_istringstream(const string_type& __s,
                                                                      ios_base::openmode __wch)
    : basic_istream<_CharT, _Traits>(&__sb_),
      __sb_(__s, __wch | ios_base::in)
{
}

#ifdef _LIBCPP_MOVE

template <class _CharT, class _Traits, class _Allocator>
inline _LIBCPP_INLINE_VISIBILITY
basic_istringstream<_CharT, _Traits, _Allocator>::basic_istringstream(basic_istringstream&& __rhs)
    : basic_istream<_CharT, _Traits>(_STD::move(__rhs)),
      __sb_(_STD::move(__rhs.__sb_))
{
    basic_istream<_CharT, _Traits>::set_rdbuf(&__sb_);
}

template <class _CharT, class _Traits, class _Allocator>
basic_istringstream<_CharT, _Traits, _Allocator>&
basic_istringstream<_CharT, _Traits, _Allocator>::operator=(basic_istringstream&& __rhs)
{
    basic_istream<char_type, traits_type>::operator=(_STD::move(__rhs));
    __sb_ = _STD::move(__rhs.__sb_);
    return *this;
}

#endif

template <class _CharT, class _Traits, class _Allocator>
inline _LIBCPP_INLINE_VISIBILITY
void
basic_istringstream<_CharT, _Traits, _Allocator>::swap(basic_istringstream& __rhs)
{
    basic_istream<char_type, traits_type>::swap(__rhs);
    __sb_.swap(__rhs.__sb_);
}

template <class _CharT, class _Traits, class _Allocator>
inline _LIBCPP_INLINE_VISIBILITY
void
swap(basic_istringstream<_CharT, _Traits, _Allocator>& __x,
     basic_istringstream<_CharT, _Traits, _Allocator>& __y)
{
    __x.swap(__y);
}

template <class _CharT, class _Traits, class _Allocator>
inline _LIBCPP_INLINE_VISIBILITY
basic_stringbuf<_CharT, _Traits, _Allocator>*
basic_istringstream<_CharT, _Traits, _Allocator>::rdbuf() const
{
    return const_cast<basic_stringbuf<char_type, traits_type, allocator_type>*>(&__sb_);
}

template <class _CharT, class _Traits, class _Allocator>
inline _LIBCPP_INLINE_VISIBILITY
basic_string<_CharT, _Traits, _Allocator>
basic_istringstream<_CharT, _Traits, _Allocator>::str() const
{
    return __sb_.str();
}

template <class _CharT, class _Traits, class _Allocator>
inline _LIBCPP_INLINE_VISIBILITY
void
basic_istringstream<_CharT, _Traits, _Allocator>::str(const string_type& __s)
{
    __sb_.str(__s);
}

// basic_ostringstream

template <class _CharT, class _Traits, class _Allocator>
class basic_ostringstream
    : public basic_ostream<_CharT, _Traits>
{
public:
    typedef _CharT                         char_type;
    typedef _Traits                        traits_type;
    typedef typename traits_type::int_type int_type;
    typedef typename traits_type::pos_type pos_type;
    typedef typename traits_type::off_type off_type;
    typedef _Allocator                     allocator_type;

    typedef basic_string<char_type, traits_type, allocator_type> string_type;

private:
    basic_stringbuf<char_type, traits_type, allocator_type> __sb_;

public:
    // 27.8.2.1 Constructors:
    explicit basic_ostringstream(ios_base::openmode __wch = ios_base::out);
    explicit basic_ostringstream(const string_type& __s,
                                 ios_base::openmode __wch = ios_base::out);
#ifdef _LIBCPP_MOVE
    basic_ostringstream(basic_ostringstream&& __rhs);

    // 27.8.2.2 Assign and swap:
    basic_ostringstream& operator=(basic_ostringstream&& __rhs);
#endif
    void swap(basic_ostringstream& __rhs);

    // 27.8.2.3 Members:
    basic_stringbuf<char_type, traits_type, allocator_type>* rdbuf() const;
    string_type str() const;
    void str(const string_type& __s);
};

template <class _CharT, class _Traits, class _Allocator>
inline _LIBCPP_INLINE_VISIBILITY
basic_ostringstream<_CharT, _Traits, _Allocator>::basic_ostringstream(ios_base::openmode __wch)
    : basic_ostream<_CharT, _Traits>(&__sb_),
      __sb_(__wch | ios_base::out)
{
}

template <class _CharT, class _Traits, class _Allocator>
inline _LIBCPP_INLINE_VISIBILITY
basic_ostringstream<_CharT, _Traits, _Allocator>::basic_ostringstream(const string_type& __s,
                                                                      ios_base::openmode __wch)
    : basic_ostream<_CharT, _Traits>(&__sb_),
      __sb_(__s, __wch | ios_base::out)
{
}

#ifdef _LIBCPP_MOVE

template <class _CharT, class _Traits, class _Allocator>
inline _LIBCPP_INLINE_VISIBILITY
basic_ostringstream<_CharT, _Traits, _Allocator>::basic_ostringstream(basic_ostringstream&& __rhs)
    : basic_ostream<_CharT, _Traits>(_STD::move(__rhs)),
      __sb_(_STD::move(__rhs.__sb_))
{
    basic_ostream<_CharT, _Traits>::set_rdbuf(&__sb_);
}

template <class _CharT, class _Traits, class _Allocator>
basic_ostringstream<_CharT, _Traits, _Allocator>&
basic_ostringstream<_CharT, _Traits, _Allocator>::operator=(basic_ostringstream&& __rhs)
{
    basic_ostream<char_type, traits_type>::operator=(_STD::move(__rhs));
    __sb_ = _STD::move(__rhs.__sb_);
    return *this;
}

#endif

template <class _CharT, class _Traits, class _Allocator>
inline _LIBCPP_INLINE_VISIBILITY
void
basic_ostringstream<_CharT, _Traits, _Allocator>::swap(basic_ostringstream& __rhs)
{
    basic_ostream<char_type, traits_type>::swap(__rhs);
    __sb_.swap(__rhs.__sb_);
}

template <class _CharT, class _Traits, class _Allocator>
inline _LIBCPP_INLINE_VISIBILITY
void
swap(basic_ostringstream<_CharT, _Traits, _Allocator>& __x,
     basic_ostringstream<_CharT, _Traits, _Allocator>& __y)
{
    __x.swap(__y);
}

template <class _CharT, class _Traits, class _Allocator>
inline _LIBCPP_INLINE_VISIBILITY
basic_stringbuf<_CharT, _Traits, _Allocator>*
basic_ostringstream<_CharT, _Traits, _Allocator>::rdbuf() const
{
    return const_cast<basic_stringbuf<char_type, traits_type, allocator_type>*>(&__sb_);
}

template <class _CharT, class _Traits, class _Allocator>
inline _LIBCPP_INLINE_VISIBILITY
basic_string<_CharT, _Traits, _Allocator>
basic_ostringstream<_CharT, _Traits, _Allocator>::str() const
{
    return __sb_.str();
}

template <class _CharT, class _Traits, class _Allocator>
inline _LIBCPP_INLINE_VISIBILITY
void
basic_ostringstream<_CharT, _Traits, _Allocator>::str(const string_type& __s)
{
    __sb_.str(__s);
}

// basic_stringstream

template <class _CharT, class _Traits, class _Allocator>
class basic_stringstream
    : public basic_iostream<_CharT, _Traits>
{
public:
    typedef _CharT                         char_type;
    typedef _Traits                        traits_type;
    typedef typename traits_type::int_type int_type;
    typedef typename traits_type::pos_type pos_type;
    typedef typename traits_type::off_type off_type;
    typedef _Allocator                     allocator_type;

    typedef basic_string<char_type, traits_type, allocator_type> string_type;

private:
    basic_stringbuf<char_type, traits_type, allocator_type> __sb_;

public:
    // 27.8.2.1 Constructors:
    explicit basic_stringstream(ios_base::openmode __wch = ios_base::in | ios_base::out);
    explicit basic_stringstream(const string_type& __s,
                                ios_base::openmode __wch = ios_base::in | ios_base::out);
#ifdef _LIBCPP_MOVE
    basic_stringstream(basic_stringstream&& __rhs);

    // 27.8.2.2 Assign and swap:
    basic_stringstream& operator=(basic_stringstream&& __rhs);
#endif
    void swap(basic_stringstream& __rhs);

    // 27.8.2.3 Members:
    basic_stringbuf<char_type, traits_type, allocator_type>* rdbuf() const;
    string_type str() const;
    void str(const string_type& __s);
};

template <class _CharT, class _Traits, class _Allocator>
inline _LIBCPP_INLINE_VISIBILITY
basic_stringstream<_CharT, _Traits, _Allocator>::basic_stringstream(ios_base::openmode __wch)
    : basic_iostream<_CharT, _Traits>(&__sb_),
      __sb_(__wch)
{
}

template <class _CharT, class _Traits, class _Allocator>
inline _LIBCPP_INLINE_VISIBILITY
basic_stringstream<_CharT, _Traits, _Allocator>::basic_stringstream(const string_type& __s,
                                                                    ios_base::openmode __wch)
    : basic_iostream<_CharT, _Traits>(&__sb_),
      __sb_(__s, __wch)
{
}

#ifdef _LIBCPP_MOVE

template <class _CharT, class _Traits, class _Allocator>
inline _LIBCPP_INLINE_VISIBILITY
basic_stringstream<_CharT, _Traits, _Allocator>::basic_stringstream(basic_stringstream&& __rhs)
    : basic_iostream<_CharT, _Traits>(_STD::move(__rhs)),
      __sb_(_STD::move(__rhs.__sb_))
{
    basic_istream<_CharT, _Traits>::set_rdbuf(&__sb_);
}

template <class _CharT, class _Traits, class _Allocator>
basic_stringstream<_CharT, _Traits, _Allocator>&
basic_stringstream<_CharT, _Traits, _Allocator>::operator=(basic_stringstream&& __rhs)
{
    basic_iostream<char_type, traits_type>::operator=(_STD::move(__rhs));
    __sb_ = _STD::move(__rhs.__sb_);
    return *this;
}

#endif

template <class _CharT, class _Traits, class _Allocator>
inline _LIBCPP_INLINE_VISIBILITY
void
basic_stringstream<_CharT, _Traits, _Allocator>::swap(basic_stringstream& __rhs)
{
    basic_iostream<char_type, traits_type>::swap(__rhs);
    __sb_.swap(__rhs.__sb_);
}

template <class _CharT, class _Traits, class _Allocator>
inline _LIBCPP_INLINE_VISIBILITY
void
swap(basic_stringstream<_CharT, _Traits, _Allocator>& __x,
     basic_stringstream<_CharT, _Traits, _Allocator>& __y)
{
    __x.swap(__y);
}

template <class _CharT, class _Traits, class _Allocator>
inline _LIBCPP_INLINE_VISIBILITY
basic_stringbuf<_CharT, _Traits, _Allocator>*
basic_stringstream<_CharT, _Traits, _Allocator>::rdbuf() const
{
    return const_cast<basic_stringbuf<char_type, traits_type, allocator_type>*>(&__sb_);
}

template <class _CharT, class _Traits, class _Allocator>
inline _LIBCPP_INLINE_VISIBILITY
basic_string<_CharT, _Traits, _Allocator>
basic_stringstream<_CharT, _Traits, _Allocator>::str() const
{
    return __sb_.str();
}

template <class _CharT, class _Traits, class _Allocator>
inline _LIBCPP_INLINE_VISIBILITY
void
basic_stringstream<_CharT, _Traits, _Allocator>::str(const string_type& __s)
{
    __sb_.str(__s);
}

_LIBCPP_END_NAMESPACE_STD

#endif  // _LIBCPP_SSTREAM