llvm-project/libcxx/include/ostream

// -*- C++ -*-
//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//

#ifndef _LIBCPP_OSTREAM
#define _LIBCPP_OSTREAM

/*
    ostream synopsis

template <class charT, class traits = char_traits<charT> >
class basic_ostream
    : virtual public basic_ios<charT,traits>
{
public:
    // types (inherited from basic_ios (27.5.4)):
    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;

    // 27.7.2.2 Constructor/destructor:
    explicit basic_ostream(basic_streambuf<char_type,traits>* sb);
    basic_ostream(basic_ostream&& rhs);
    virtual ~basic_ostream();

    // 27.7.2.3 Assign/swap
    basic_ostream& operator=(const basic_ostream& rhs) = delete; // C++14
    basic_ostream& operator=(basic_ostream&& rhs);
    void swap(basic_ostream& rhs);

    // 27.7.2.4 Prefix/suffix:
    class sentry;

    // 27.7.2.6 Formatted output:
    basic_ostream& operator<<(basic_ostream& (*pf)(basic_ostream&));
    basic_ostream& operator<<(basic_ios<charT, traits>& (*pf)(basic_ios<charT,traits>&));
    basic_ostream& operator<<(ios_base& (*pf)(ios_base&));
    basic_ostream& operator<<(bool n);
    basic_ostream& operator<<(short n);
    basic_ostream& operator<<(unsigned short n);
    basic_ostream& operator<<(int n);
    basic_ostream& operator<<(unsigned int n);
    basic_ostream& operator<<(long n);
    basic_ostream& operator<<(unsigned long n);
    basic_ostream& operator<<(long long n);
    basic_ostream& operator<<(unsigned long long n);
    basic_ostream& operator<<(float f);
    basic_ostream& operator<<(double f);
    basic_ostream& operator<<(long double f);
    basic_ostream& operator<<(const void* p);
    basic_ostream& operator<<(const volatile void* val); // C++23
    basic_ostream& operator<<(basic_streambuf<char_type,traits>* sb);
    basic_ostream& operator<<(nullptr_t);

    // 27.7.2.7 Unformatted output:
    basic_ostream& put(char_type c);
    basic_ostream& write(const char_type* s, streamsize n);
    basic_ostream& flush();

    // 27.7.2.5 seeks:
    pos_type tellp();
    basic_ostream& seekp(pos_type);
    basic_ostream& seekp(off_type, ios_base::seekdir);
protected:
    basic_ostream(const basic_ostream& rhs) = delete;
    basic_ostream(basic_ostream&& rhs);
    // 27.7.3.3 Assign/swap
    basic_ostream& operator=(basic_ostream& rhs) = delete;
    basic_ostream& operator=(const basic_ostream&& rhs);
    void swap(basic_ostream& rhs);
};

// 27.7.2.6.4 character inserters

template<class charT, class traits>
  basic_ostream<charT,traits>& operator<<(basic_ostream<charT,traits>&, charT);

template<class charT, class traits>
  basic_ostream<charT,traits>& operator<<(basic_ostream<charT,traits>&, char);

template<class traits>
  basic_ostream<char,traits>& operator<<(basic_ostream<char,traits>&, char);

// signed and unsigned

template<class traits>
  basic_ostream<char,traits>& operator<<(basic_ostream<char,traits>&, signed char);

template<class traits>
  basic_ostream<char,traits>& operator<<(basic_ostream<char,traits>&, unsigned char);

// NTBS
template<class charT, class traits>
  basic_ostream<charT,traits>& operator<<(basic_ostream<charT,traits>&, const charT*);

template<class charT, class traits>
  basic_ostream<charT,traits>& operator<<(basic_ostream<charT,traits>&, const char*);

template<class traits>
  basic_ostream<char,traits>& operator<<(basic_ostream<char,traits>&, const char*);

// signed and unsigned
template<class traits>
basic_ostream<char,traits>& operator<<(basic_ostream<char,traits>&, const signed char*);

template<class traits>
  basic_ostream<char,traits>& operator<<(basic_ostream<char,traits>&, const unsigned char*);

// swap:
template <class charT, class traits>
  void swap(basic_ostream<charT, traits>& x, basic_ostream<charT, traits>& y);

template <class charT, class traits>
  basic_ostream<charT,traits>& endl(basic_ostream<charT,traits>& os);

template <class charT, class traits>
  basic_ostream<charT,traits>& ends(basic_ostream<charT,traits>& os);

template <class charT, class traits>
  basic_ostream<charT,traits>& flush(basic_ostream<charT,traits>& os);

// rvalue stream insertion
template <class Stream, class T>
  Stream&& operator<<(Stream&& os, const T& x);

}  // std

*/

#include <__config>
#include <bitset>
#include <ios>
#include <iterator>
#include <locale>
#include <streambuf>
#include <version>

#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
#pragma GCC system_header
#endif

_LIBCPP_BEGIN_NAMESPACE_STD

template <class _CharT, class _Traits>
class _LIBCPP_TEMPLATE_VIS basic_ostream
    : virtual public basic_ios<_CharT, _Traits>
{
public:
    // types (inherited from basic_ios (27.5.4)):
    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;

    // 27.7.2.2 Constructor/destructor:
    inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1
    explicit basic_ostream(basic_streambuf<char_type, traits_type>* __sb)
    { this->init(__sb); }
    virtual ~basic_ostream();
protected:
    inline _LIBCPP_INLINE_VISIBILITY
    basic_ostream(basic_ostream&& __rhs);

    // 27.7.2.3 Assign/swap
    inline _LIBCPP_INLINE_VISIBILITY
    basic_ostream& operator=(basic_ostream&& __rhs);

    inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1
    void swap(basic_ostream& __rhs)
    { basic_ios<char_type, traits_type>::swap(__rhs); }

    basic_ostream           (const basic_ostream& __rhs) = delete;
    basic_ostream& operator=(const basic_ostream& __rhs) = delete;

public:
    // 27.7.2.4 Prefix/suffix:
    class _LIBCPP_TEMPLATE_VIS sentry;

    // 27.7.2.6 Formatted output:
    inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1
    basic_ostream& operator<<(basic_ostream& (*__pf)(basic_ostream&))
    { return __pf(*this); }

    inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1
    basic_ostream& operator<<(basic_ios<char_type, traits_type>&
                              (*__pf)(basic_ios<char_type,traits_type>&))
    { __pf(*this); return *this; }

    inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1
    basic_ostream& operator<<(ios_base& (*__pf)(ios_base&))
    { __pf(*this); return *this; }

    basic_ostream& operator<<(bool __n);
    basic_ostream& operator<<(short __n);
    basic_ostream& operator<<(unsigned short __n);
    basic_ostream& operator<<(int __n);
    basic_ostream& operator<<(unsigned int __n);
    basic_ostream& operator<<(long __n);
    basic_ostream& operator<<(unsigned long __n);
    basic_ostream& operator<<(long long __n);
    basic_ostream& operator<<(unsigned long long __n);
    basic_ostream& operator<<(float __f);
    basic_ostream& operator<<(double __f);
    basic_ostream& operator<<(long double __f);
    basic_ostream& operator<<(const void* __p);

#if _LIBCPP_STD_VER > 20
    _LIBCPP_HIDE_FROM_ABI
    basic_ostream& operator<<(const volatile void* __p) {
        return operator<<(const_cast<const void*>(__p));
    }
#endif

    basic_ostream& operator<<(basic_streambuf<char_type, traits_type>* __sb);

    _LIBCPP_INLINE_VISIBILITY
    basic_ostream& operator<<(nullptr_t)
    { return *this << "nullptr"; }

    // 27.7.2.7 Unformatted output:
    basic_ostream& put(char_type __c);
    basic_ostream& write(const char_type* __s, streamsize __n);
    basic_ostream& flush();

    // 27.7.2.5 seeks:
    inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1
    pos_type tellp();
    inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1
    basic_ostream& seekp(pos_type __pos);
    inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1
    basic_ostream& seekp(off_type __off, ios_base::seekdir __dir);

protected:
    _LIBCPP_INLINE_VISIBILITY
    basic_ostream() {}  // extension, intentially does not initialize
};

template <class _CharT, class _Traits>
class _LIBCPP_TEMPLATE_VIS basic_ostream<_CharT, _Traits>::sentry
{
    bool __ok_;
    basic_ostream<_CharT, _Traits>& __os_;

public:
    explicit sentry(basic_ostream<_CharT, _Traits>& __os);
    ~sentry();
    sentry(const sentry&) = delete;
    sentry& operator=(const sentry&) = delete;

    _LIBCPP_INLINE_VISIBILITY
    explicit operator bool() const {return __ok_;}
};

template <class _CharT, class _Traits>
basic_ostream<_CharT, _Traits>::sentry::sentry(basic_ostream<_CharT, _Traits>& __os)
    : __ok_(false),
      __os_(__os)
{
    if (__os.good())
    {
        if (__os.tie())
            __os.tie()->flush();
        __ok_ = true;
    }
}

template <class _CharT, class _Traits>
basic_ostream<_CharT, _Traits>::sentry::~sentry()
{
    if (__os_.rdbuf() && __os_.good() && (__os_.flags() & ios_base::unitbuf)
                      && !uncaught_exception())
    {
#ifndef _LIBCPP_NO_EXCEPTIONS
        try
        {
#endif // _LIBCPP_NO_EXCEPTIONS
            if (__os_.rdbuf()->pubsync() == -1)
                __os_.setstate(ios_base::badbit);
#ifndef _LIBCPP_NO_EXCEPTIONS
        }
        catch (...)
        {
        }
#endif // _LIBCPP_NO_EXCEPTIONS
    }
}

template <class _CharT, class _Traits>
basic_ostream<_CharT, _Traits>::basic_ostream(basic_ostream&& __rhs)
{
    this->move(__rhs);
}

template <class _CharT, class _Traits>
basic_ostream<_CharT, _Traits>&
basic_ostream<_CharT, _Traits>::operator=(basic_ostream&& __rhs)
{
    swap(__rhs);
    return *this;
}

template <class _CharT, class _Traits>
basic_ostream<_CharT, _Traits>::~basic_ostream()
{
}

template <class _CharT, class _Traits>
basic_ostream<_CharT, _Traits>&
basic_ostream<_CharT, _Traits>::operator<<(basic_streambuf<char_type, traits_type>* __sb)
{
#ifndef _LIBCPP_NO_EXCEPTIONS
    try
    {
#endif // _LIBCPP_NO_EXCEPTIONS
        sentry __s(*this);
        if (__s)
        {
            if (__sb)
            {
#ifndef _LIBCPP_NO_EXCEPTIONS
                try
                {
#endif // _LIBCPP_NO_EXCEPTIONS
                    typedef istreambuf_iterator<_CharT, _Traits> _Ip;
                    typedef ostreambuf_iterator<_CharT, _Traits> _Op;
                    _Ip __i(__sb);
                    _Ip __eof;
                    _Op __o(*this);
                    size_t __c = 0;
                    for (; __i != __eof; ++__i, ++__o, ++__c)
                    {
                        *__o = *__i;
                        if (__o.failed())
                            break;
                    }
                    if (__c == 0)
                        this->setstate(ios_base::failbit);
#ifndef _LIBCPP_NO_EXCEPTIONS
                }
                catch (...)
                {
                    this->__set_failbit_and_consider_rethrow();
                }
#endif // _LIBCPP_NO_EXCEPTIONS
            }
            else
                this->setstate(ios_base::badbit);
        }
#ifndef _LIBCPP_NO_EXCEPTIONS
    }
    catch (...)
    {
        this->__set_badbit_and_consider_rethrow();
    }
#endif // _LIBCPP_NO_EXCEPTIONS
    return *this;
}

template <class _CharT, class _Traits>
basic_ostream<_CharT, _Traits>&
basic_ostream<_CharT, _Traits>::operator<<(bool __n)
{
#ifndef _LIBCPP_NO_EXCEPTIONS
    try
    {
#endif // _LIBCPP_NO_EXCEPTIONS
        sentry __s(*this);
        if (__s)
        {
            typedef num_put<char_type, ostreambuf_iterator<char_type, traits_type> > _Fp;
            const _Fp& __f = use_facet<_Fp>(this->getloc());
            if (__f.put(*this, *this, this->fill(), __n).failed())
                this->setstate(ios_base::badbit | ios_base::failbit);
        }
#ifndef _LIBCPP_NO_EXCEPTIONS
    }
    catch (...)
    {
        this->__set_badbit_and_consider_rethrow();
    }
#endif // _LIBCPP_NO_EXCEPTIONS
    return *this;
}

template <class _CharT, class _Traits>
basic_ostream<_CharT, _Traits>&
basic_ostream<_CharT, _Traits>::operator<<(short __n)
{
#ifndef _LIBCPP_NO_EXCEPTIONS
    try
    {
#endif // _LIBCPP_NO_EXCEPTIONS
        sentry __s(*this);
        if (__s)
        {
            ios_base::fmtflags __flags = ios_base::flags() & ios_base::basefield;
            typedef num_put<char_type, ostreambuf_iterator<char_type, traits_type> > _Fp;
            const _Fp& __f = use_facet<_Fp>(this->getloc());
            if (__f.put(*this, *this, this->fill(),
                        __flags == ios_base::oct || __flags == ios_base::hex ?
                        static_cast<long>(static_cast<unsigned short>(__n))  :
                        static_cast<long>(__n)).failed())
                this->setstate(ios_base::badbit | ios_base::failbit);
        }
#ifndef _LIBCPP_NO_EXCEPTIONS
    }
    catch (...)
    {
        this->__set_badbit_and_consider_rethrow();
    }
#endif // _LIBCPP_NO_EXCEPTIONS
    return *this;
}

template <class _CharT, class _Traits>
basic_ostream<_CharT, _Traits>&
basic_ostream<_CharT, _Traits>::operator<<(unsigned short __n)
{
#ifndef _LIBCPP_NO_EXCEPTIONS
    try
    {
#endif // _LIBCPP_NO_EXCEPTIONS
        sentry __s(*this);
        if (__s)
        {
            typedef num_put<char_type, ostreambuf_iterator<char_type, traits_type> > _Fp;
            const _Fp& __f = use_facet<_Fp>(this->getloc());
            if (__f.put(*this, *this, this->fill(), static_cast<unsigned long>(__n)).failed())
                this->setstate(ios_base::badbit | ios_base::failbit);
        }
#ifndef _LIBCPP_NO_EXCEPTIONS
    }
    catch (...)
    {
        this->__set_badbit_and_consider_rethrow();
    }
#endif // _LIBCPP_NO_EXCEPTIONS
    return *this;
}

template <class _CharT, class _Traits>
basic_ostream<_CharT, _Traits>&
basic_ostream<_CharT, _Traits>::operator<<(int __n)
{
#ifndef _LIBCPP_NO_EXCEPTIONS
    try
    {
#endif // _LIBCPP_NO_EXCEPTIONS
        sentry __s(*this);
        if (__s)
        {
            ios_base::fmtflags __flags = ios_base::flags() & ios_base::basefield;
            typedef num_put<char_type, ostreambuf_iterator<char_type, traits_type> > _Fp;
            const _Fp& __f = use_facet<_Fp>(this->getloc());
            if (__f.put(*this, *this, this->fill(),
                        __flags == ios_base::oct || __flags == ios_base::hex ?
                        static_cast<long>(static_cast<unsigned int>(__n))  :
                        static_cast<long>(__n)).failed())
                this->setstate(ios_base::badbit | ios_base::failbit);
        }
#ifndef _LIBCPP_NO_EXCEPTIONS
    }
    catch (...)
    {
        this->__set_badbit_and_consider_rethrow();
    }
#endif // _LIBCPP_NO_EXCEPTIONS
    return *this;
}

template <class _CharT, class _Traits>
basic_ostream<_CharT, _Traits>&
basic_ostream<_CharT, _Traits>::operator<<(unsigned int __n)
{
#ifndef _LIBCPP_NO_EXCEPTIONS
    try
    {
#endif // _LIBCPP_NO_EXCEPTIONS
        sentry __s(*this);
        if (__s)
        {
            typedef num_put<char_type, ostreambuf_iterator<char_type, traits_type> > _Fp;
            const _Fp& __f = use_facet<_Fp>(this->getloc());
            if (__f.put(*this, *this, this->fill(), static_cast<unsigned long>(__n)).failed())
                this->setstate(ios_base::badbit | ios_base::failbit);
        }
#ifndef _LIBCPP_NO_EXCEPTIONS
    }
    catch (...)
    {
        this->__set_badbit_and_consider_rethrow();
    }
#endif // _LIBCPP_NO_EXCEPTIONS
    return *this;
}

template <class _CharT, class _Traits>
basic_ostream<_CharT, _Traits>&
basic_ostream<_CharT, _Traits>::operator<<(long __n)
{
#ifndef _LIBCPP_NO_EXCEPTIONS
    try
    {
#endif // _LIBCPP_NO_EXCEPTIONS
        sentry __s(*this);
        if (__s)
        {
            typedef num_put<char_type, ostreambuf_iterator<char_type, traits_type> > _Fp;
            const _Fp& __f = use_facet<_Fp>(this->getloc());
            if (__f.put(*this, *this, this->fill(), __n).failed())
                this->setstate(ios_base::badbit | ios_base::failbit);
        }
#ifndef _LIBCPP_NO_EXCEPTIONS
    }
    catch (...)
    {
        this->__set_badbit_and_consider_rethrow();
    }
#endif // _LIBCPP_NO_EXCEPTIONS
    return *this;
}

template <class _CharT, class _Traits>
basic_ostream<_CharT, _Traits>&
basic_ostream<_CharT, _Traits>::operator<<(unsigned long __n)
{
#ifndef _LIBCPP_NO_EXCEPTIONS
    try
    {
#endif // _LIBCPP_NO_EXCEPTIONS
        sentry __s(*this);
        if (__s)
        {
            typedef num_put<char_type, ostreambuf_iterator<char_type, traits_type> > _Fp;
            const _Fp& __f = use_facet<_Fp>(this->getloc());
            if (__f.put(*this, *this, this->fill(), __n).failed())
                this->setstate(ios_base::badbit | ios_base::failbit);
        }
#ifndef _LIBCPP_NO_EXCEPTIONS
    }
    catch (...)
    {
        this->__set_badbit_and_consider_rethrow();
    }
#endif // _LIBCPP_NO_EXCEPTIONS
    return *this;
}

template <class _CharT, class _Traits>
basic_ostream<_CharT, _Traits>&
basic_ostream<_CharT, _Traits>::operator<<(long long __n)
{
#ifndef _LIBCPP_NO_EXCEPTIONS
    try
    {
#endif // _LIBCPP_NO_EXCEPTIONS
        sentry __s(*this);
        if (__s)
        {
            typedef num_put<char_type, ostreambuf_iterator<char_type, traits_type> > _Fp;
            const _Fp& __f = use_facet<_Fp>(this->getloc());
            if (__f.put(*this, *this, this->fill(), __n).failed())
                this->setstate(ios_base::badbit | ios_base::failbit);
        }
#ifndef _LIBCPP_NO_EXCEPTIONS
    }
    catch (...)
    {
        this->__set_badbit_and_consider_rethrow();
    }
#endif // _LIBCPP_NO_EXCEPTIONS
    return *this;
}

template <class _CharT, class _Traits>
basic_ostream<_CharT, _Traits>&
basic_ostream<_CharT, _Traits>::operator<<(unsigned long long __n)
{
#ifndef _LIBCPP_NO_EXCEPTIONS
    try
    {
#endif // _LIBCPP_NO_EXCEPTIONS
        sentry __s(*this);
        if (__s)
        {
            typedef num_put<char_type, ostreambuf_iterator<char_type, traits_type> > _Fp;
            const _Fp& __f = use_facet<_Fp>(this->getloc());
            if (__f.put(*this, *this, this->fill(), __n).failed())
                this->setstate(ios_base::badbit | ios_base::failbit);
        }
#ifndef _LIBCPP_NO_EXCEPTIONS
    }
    catch (...)
    {
        this->__set_badbit_and_consider_rethrow();
    }
#endif // _LIBCPP_NO_EXCEPTIONS
    return *this;
}

template <class _CharT, class _Traits>
basic_ostream<_CharT, _Traits>&
basic_ostream<_CharT, _Traits>::operator<<(float __n)
{
#ifndef _LIBCPP_NO_EXCEPTIONS
    try
    {
#endif // _LIBCPP_NO_EXCEPTIONS
        sentry __s(*this);
        if (__s)
        {
            typedef num_put<char_type, ostreambuf_iterator<char_type, traits_type> > _Fp;
            const _Fp& __f = use_facet<_Fp>(this->getloc());
            if (__f.put(*this, *this, this->fill(), static_cast<double>(__n)).failed())
                this->setstate(ios_base::badbit | ios_base::failbit);
        }
#ifndef _LIBCPP_NO_EXCEPTIONS
    }
    catch (...)
    {
        this->__set_badbit_and_consider_rethrow();
    }
#endif // _LIBCPP_NO_EXCEPTIONS
    return *this;
}

template <class _CharT, class _Traits>
basic_ostream<_CharT, _Traits>&
basic_ostream<_CharT, _Traits>::operator<<(double __n)
{
#ifndef _LIBCPP_NO_EXCEPTIONS
    try
    {
#endif // _LIBCPP_NO_EXCEPTIONS
        sentry __s(*this);
        if (__s)
        {
            typedef num_put<char_type, ostreambuf_iterator<char_type, traits_type> > _Fp;
            const _Fp& __f = use_facet<_Fp>(this->getloc());
            if (__f.put(*this, *this, this->fill(), __n).failed())
                this->setstate(ios_base::badbit | ios_base::failbit);
        }
#ifndef _LIBCPP_NO_EXCEPTIONS
    }
    catch (...)
    {
        this->__set_badbit_and_consider_rethrow();
    }
#endif // _LIBCPP_NO_EXCEPTIONS
    return *this;
}

template <class _CharT, class _Traits>
basic_ostream<_CharT, _Traits>&
basic_ostream<_CharT, _Traits>::operator<<(long double __n)
{
#ifndef _LIBCPP_NO_EXCEPTIONS
    try
    {
#endif // _LIBCPP_NO_EXCEPTIONS
        sentry __s(*this);
        if (__s)
        {
            typedef num_put<char_type, ostreambuf_iterator<char_type, traits_type> > _Fp;
            const _Fp& __f = use_facet<_Fp>(this->getloc());
            if (__f.put(*this, *this, this->fill(), __n).failed())
                this->setstate(ios_base::badbit | ios_base::failbit);
        }
#ifndef _LIBCPP_NO_EXCEPTIONS
    }
    catch (...)
    {
        this->__set_badbit_and_consider_rethrow();
    }
#endif // _LIBCPP_NO_EXCEPTIONS
    return *this;
}

template <class _CharT, class _Traits>
basic_ostream<_CharT, _Traits>&
basic_ostream<_CharT, _Traits>::operator<<(const void* __n)
{
#ifndef _LIBCPP_NO_EXCEPTIONS
    try
    {
#endif // _LIBCPP_NO_EXCEPTIONS
        sentry __s(*this);
        if (__s)
        {
            typedef num_put<char_type, ostreambuf_iterator<char_type, traits_type> > _Fp;
            const _Fp& __f = use_facet<_Fp>(this->getloc());
            if (__f.put(*this, *this, this->fill(), __n).failed())
                this->setstate(ios_base::badbit | ios_base::failbit);
        }
#ifndef _LIBCPP_NO_EXCEPTIONS
    }
    catch (...)
    {
        this->__set_badbit_and_consider_rethrow();
    }
#endif // _LIBCPP_NO_EXCEPTIONS
    return *this;
}

template<class _CharT, class _Traits>
basic_ostream<_CharT, _Traits>&
__put_character_sequence(basic_ostream<_CharT, _Traits>& __os,
                          const _CharT* __str, size_t __len)
{
#ifndef _LIBCPP_NO_EXCEPTIONS
    try
    {
#endif // _LIBCPP_NO_EXCEPTIONS
        typename basic_ostream<_CharT, _Traits>::sentry __s(__os);
        if (__s)
        {
            typedef ostreambuf_iterator<_CharT, _Traits> _Ip;
            if (__pad_and_output(_Ip(__os),
                                 __str,
                                 (__os.flags() & ios_base::adjustfield) == ios_base::left ?
                                     __str + __len :
                                     __str,
                                 __str + __len,
                                 __os,
                                 __os.fill()).failed())
                __os.setstate(ios_base::badbit | ios_base::failbit);
        }
#ifndef _LIBCPP_NO_EXCEPTIONS
    }
    catch (...)
    {
        __os.__set_badbit_and_consider_rethrow();
    }
#endif // _LIBCPP_NO_EXCEPTIONS
    return __os;
}


template<class _CharT, class _Traits>
basic_ostream<_CharT, _Traits>&
operator<<(basic_ostream<_CharT, _Traits>& __os, _CharT __c)
{
    return _VSTD::__put_character_sequence(__os, &__c, 1);
}

template<class _CharT, class _Traits>
basic_ostream<_CharT, _Traits>&
operator<<(basic_ostream<_CharT, _Traits>& __os, char __cn)
{
#ifndef _LIBCPP_NO_EXCEPTIONS
    try
    {
#endif // _LIBCPP_NO_EXCEPTIONS
        typename basic_ostream<_CharT, _Traits>::sentry __s(__os);
        if (__s)
        {
            _CharT __c = __os.widen(__cn);
            typedef ostreambuf_iterator<_CharT, _Traits> _Ip;
            if (__pad_and_output(_Ip(__os),
                                 &__c,
                                 (__os.flags() & ios_base::adjustfield) == ios_base::left ?
                                     &__c + 1 :
                                     &__c,
                                 &__c + 1,
                                 __os,
                                 __os.fill()).failed())
                __os.setstate(ios_base::badbit | ios_base::failbit);
        }
#ifndef _LIBCPP_NO_EXCEPTIONS
    }
    catch (...)
    {
        __os.__set_badbit_and_consider_rethrow();
    }
#endif // _LIBCPP_NO_EXCEPTIONS
    return __os;
}

template<class _Traits>
basic_ostream<char, _Traits>&
operator<<(basic_ostream<char, _Traits>& __os, char __c)
{
    return _VSTD::__put_character_sequence(__os, &__c, 1);
}

template<class _Traits>
basic_ostream<char, _Traits>&
operator<<(basic_ostream<char, _Traits>& __os, signed char __c)
{
    return _VSTD::__put_character_sequence(__os, (char *) &__c, 1);
}

template<class _Traits>
basic_ostream<char, _Traits>&
operator<<(basic_ostream<char, _Traits>& __os, unsigned char __c)
{
    return _VSTD::__put_character_sequence(__os, (char *) &__c, 1);
}

template<class _CharT, class _Traits>
basic_ostream<_CharT, _Traits>&
operator<<(basic_ostream<_CharT, _Traits>& __os, const _CharT* __str)
{
    return _VSTD::__put_character_sequence(__os, __str, _Traits::length(__str));
}

template<class _CharT, class _Traits>
basic_ostream<_CharT, _Traits>&
operator<<(basic_ostream<_CharT, _Traits>& __os, const char* __strn)
{
#ifndef _LIBCPP_NO_EXCEPTIONS
    try
    {
#endif // _LIBCPP_NO_EXCEPTIONS
        typename basic_ostream<_CharT, _Traits>::sentry __s(__os);
        if (__s)
        {
            typedef ostreambuf_iterator<_CharT, _Traits> _Ip;
            size_t __len = char_traits<char>::length(__strn);
            const int __bs = 100;
            _CharT __wbb[__bs];
            _CharT* __wb = __wbb;
            unique_ptr<_CharT, void(*)(void*)> __h(0, free);
            if (__len > __bs)
            {
                __wb = (_CharT*)malloc(__len*sizeof(_CharT));
                if (__wb == 0)
                    __throw_bad_alloc();
                __h.reset(__wb);
            }
            for (_CharT* __p = __wb; *__strn != '\0'; ++__strn, ++__p)
                *__p = __os.widen(*__strn);
            if (__pad_and_output(_Ip(__os),
                                 __wb,
                                 (__os.flags() & ios_base::adjustfield) == ios_base::left ?
                                     __wb + __len :
                                     __wb,
                                 __wb + __len,
                                 __os,
                                 __os.fill()).failed())
                __os.setstate(ios_base::badbit | ios_base::failbit);
        }
#ifndef _LIBCPP_NO_EXCEPTIONS
    }
    catch (...)
    {
        __os.__set_badbit_and_consider_rethrow();
    }
#endif // _LIBCPP_NO_EXCEPTIONS
    return __os;
}

template<class _Traits>
basic_ostream<char, _Traits>&
operator<<(basic_ostream<char, _Traits>& __os, const char* __str)
{
    return _VSTD::__put_character_sequence(__os, __str, _Traits::length(__str));
}

template<class _Traits>
basic_ostream<char, _Traits>&
operator<<(basic_ostream<char, _Traits>& __os, const signed char* __str)
{
    const char *__s = (const char *) __str;
    return _VSTD::__put_character_sequence(__os, __s, _Traits::length(__s));
}

template<class _Traits>
basic_ostream<char, _Traits>&
operator<<(basic_ostream<char, _Traits>& __os, const unsigned char* __str)
{
    const char *__s = (const char *) __str;
    return _VSTD::__put_character_sequence(__os, __s, _Traits::length(__s));
}

template <class _CharT, class _Traits>
basic_ostream<_CharT, _Traits>&
basic_ostream<_CharT, _Traits>::put(char_type __c)
{
#ifndef _LIBCPP_NO_EXCEPTIONS
    try
    {
#endif // _LIBCPP_NO_EXCEPTIONS
        sentry __s(*this);
        if (__s)
        {
            typedef ostreambuf_iterator<_CharT, _Traits> _Op;
            _Op __o(*this);
            *__o = __c;
            if (__o.failed())
                this->setstate(ios_base::badbit);
        }
#ifndef _LIBCPP_NO_EXCEPTIONS
    }
    catch (...)
    {
        this->__set_badbit_and_consider_rethrow();
    }
#endif // _LIBCPP_NO_EXCEPTIONS
    return *this;
}

template <class _CharT, class _Traits>
basic_ostream<_CharT, _Traits>&
basic_ostream<_CharT, _Traits>::write(const char_type* __s, streamsize __n)
{
#ifndef _LIBCPP_NO_EXCEPTIONS
    try
    {
#endif // _LIBCPP_NO_EXCEPTIONS
        sentry __sen(*this);
        if (__sen && __n)
        {
            if (this->rdbuf()->sputn(__s, __n) != __n)
                this->setstate(ios_base::badbit);
        }
#ifndef _LIBCPP_NO_EXCEPTIONS
    }
    catch (...)
    {
        this->__set_badbit_and_consider_rethrow();
    }
#endif // _LIBCPP_NO_EXCEPTIONS
    return *this;
}

template <class _CharT, class _Traits>
basic_ostream<_CharT, _Traits>&
basic_ostream<_CharT, _Traits>::flush()
{
#ifndef _LIBCPP_NO_EXCEPTIONS
    try
    {
#endif // _LIBCPP_NO_EXCEPTIONS
        if (this->rdbuf())
        {
            sentry __s(*this);
            if (__s)
            {
                if (this->rdbuf()->pubsync() == -1)
                    this->setstate(ios_base::badbit);
            }
        }
#ifndef _LIBCPP_NO_EXCEPTIONS
    }
    catch (...)
    {
        this->__set_badbit_and_consider_rethrow();
    }
#endif // _LIBCPP_NO_EXCEPTIONS
    return *this;
}

template <class _CharT, class _Traits>
typename basic_ostream<_CharT, _Traits>::pos_type
basic_ostream<_CharT, _Traits>::tellp()
{
    if (this->fail())
        return pos_type(-1);
    return this->rdbuf()->pubseekoff(0, ios_base::cur, ios_base::out);
}

template <class _CharT, class _Traits>
basic_ostream<_CharT, _Traits>&
basic_ostream<_CharT, _Traits>::seekp(pos_type __pos)
{
    sentry __s(*this);
    if (!this->fail())
    {
        if (this->rdbuf()->pubseekpos(__pos, ios_base::out) == pos_type(-1))
            this->setstate(ios_base::failbit);
    }
    return *this;
}

template <class _CharT, class _Traits>
basic_ostream<_CharT, _Traits>&
basic_ostream<_CharT, _Traits>::seekp(off_type __off, ios_base::seekdir __dir)
{
    sentry __s(*this);
    if (!this->fail())
    {
        if (this->rdbuf()->pubseekoff(__off, __dir, ios_base::out) == pos_type(-1))
            this->setstate(ios_base::failbit);
    }
    return *this;
}

template <class _CharT, class _Traits>
inline
basic_ostream<_CharT, _Traits>&
endl(basic_ostream<_CharT, _Traits>& __os)
{
    __os.put(__os.widen('\n'));
    __os.flush();
    return __os;
}

template <class _CharT, class _Traits>
inline
basic_ostream<_CharT, _Traits>&
ends(basic_ostream<_CharT, _Traits>& __os)
{
    __os.put(_CharT());
    return __os;
}

template <class _CharT, class _Traits>
inline
basic_ostream<_CharT, _Traits>&
flush(basic_ostream<_CharT, _Traits>& __os)
{
    __os.flush();
    return __os;
}

template <class _Stream, class _Tp, class = void>
struct __is_ostreamable : false_type { };

template <class _Stream, class _Tp>
struct __is_ostreamable<_Stream, _Tp, decltype(
    declval<_Stream>() << declval<_Tp>(), void()
)> : true_type { };

template <class _Stream, class _Tp, class = typename enable_if<
    _And<is_base_of<ios_base, _Stream>,
         __is_ostreamable<_Stream&, const _Tp&> >::value
>::type>
_LIBCPP_INLINE_VISIBILITY
_Stream&& operator<<(_Stream&& __os, const _Tp& __x)
{
    __os << __x;
    return _VSTD::move(__os);
}

template<class _CharT, class _Traits, class _Allocator>
basic_ostream<_CharT, _Traits>&
operator<<(basic_ostream<_CharT, _Traits>& __os,
           const basic_string<_CharT, _Traits, _Allocator>& __str)
{
    return _VSTD::__put_character_sequence(__os, __str.data(), __str.size());
}

template<class _CharT, class _Traits>
basic_ostream<_CharT, _Traits>&
operator<<(basic_ostream<_CharT, _Traits>& __os,
           basic_string_view<_CharT, _Traits> __sv)
{
    return _VSTD::__put_character_sequence(__os, __sv.data(), __sv.size());
}

template <class _CharT, class _Traits>
inline _LIBCPP_INLINE_VISIBILITY
basic_ostream<_CharT, _Traits>&
operator<<(basic_ostream<_CharT, _Traits>& __os, const error_code& __ec)
{
    return __os << __ec.category().name() << ':' << __ec.value();
}

template<class _CharT, class _Traits, class _Yp>
inline _LIBCPP_INLINE_VISIBILITY
basic_ostream<_CharT, _Traits>&
operator<<(basic_ostream<_CharT, _Traits>& __os, shared_ptr<_Yp> const& __p)
{
    return __os << __p.get();
}

template<class _CharT, class _Traits, class _Yp, class _Dp>
inline _LIBCPP_INLINE_VISIBILITY
typename enable_if
<
    is_same<void, typename __void_t<decltype((declval<basic_ostream<_CharT, _Traits>&>() << declval<typename unique_ptr<_Yp, _Dp>::pointer>()))>::type>::value,
    basic_ostream<_CharT, _Traits>&
>::type
operator<<(basic_ostream<_CharT, _Traits>& __os, unique_ptr<_Yp, _Dp> const& __p)
{
    return __os << __p.get();
}

template <class _CharT, class _Traits, size_t _Size>
basic_ostream<_CharT, _Traits>&
operator<<(basic_ostream<_CharT, _Traits>& __os, const bitset<_Size>& __x)
{
    return __os << __x.template to_string<_CharT, _Traits>
                        (use_facet<ctype<_CharT> >(__os.getloc()).widen('0'),
                         use_facet<ctype<_CharT> >(__os.getloc()).widen('1'));
}

_LIBCPP_EXTERN_TEMPLATE(class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_ostream<char>)
#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
_LIBCPP_EXTERN_TEMPLATE(class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_ostream<wchar_t>)
#endif

_LIBCPP_END_NAMESPACE_STD

#endif // _LIBCPP_OSTREAM