// -*- 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_EXPERIMENTAL_ITERATOR
#define _LIBCPP_EXPERIMENTAL_ITERATOR

/*
namespace std {
  namespace experimental {
    inline namespace fundamentals_v2 {

    template <class DelimT, class charT = char, class traits = char_traits<charT>>
        class ostream_joiner {
        public:
         typedef charT                        char_type;
         typedef traits                       traits_type;
         typedef basic_ostream<charT, traits> ostream_type;
         typedef output_iterator_tag          iterator_category;
         typedef void                         value_type;
         typedef void                         difference_type;
         typedef void                         pointer;
         typedef void                         reference;

         ostream_joiner(ostream_type& s, const DelimT& delimiter);
         ostream_joiner(ostream_type& s, DelimT&& delimiter);

         template<typename T>
         ostream_joiner& operator=(const T& value);

         ostream_joiner& operator*() noexcept;
         ostream_joiner& operator++() noexcept;
         ostream_joiner& operator++(int) noexcept;
   private:
      ostream_type* out_stream;   // exposition only
      DelimT delim;               // exposition only
      bool first_element;         // exposition only
   };

  template <class charT, class traits, class DelimT>
    ostream_joiner<decay_t<DelimT>, charT, traits>
    make_ostream_joiner(basic_ostream<charT, traits>& os, DelimT&& delimiter);

    } // inline namespace fundamentals_v2
  } // namespace experimental
} // namespace std

*/

#include <__assert> // all public C++ headers provide the assertion handler
#include <__memory/addressof.h>
#include <__type_traits/decay.h>
#include <__utility/forward.h>
#include <__utility/move.h>
#include <experimental/__config>
#include <iterator>

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

_LIBCPP_PUSH_MACROS
#include <__undef_macros>

#if _LIBCPP_STD_VER >= 14

_LIBCPP_BEGIN_NAMESPACE_LFTS

template <class _Delim, class _CharT = char, class _Traits = char_traits<_CharT>>
class ostream_joiner {
public:
  typedef _CharT char_type;
  typedef _Traits traits_type;
  typedef basic_ostream<char_type, traits_type> ostream_type;
  typedef output_iterator_tag iterator_category;
  typedef void value_type;
  typedef void difference_type;
  typedef void pointer;
  typedef void reference;

  _LIBCPP_HIDE_FROM_ABI ostream_joiner(ostream_type& __os, _Delim&& __d)
      : __output_iter_(std::addressof(__os)), __delim_(std::move(__d)), __first_(true) {}

  _LIBCPP_HIDE_FROM_ABI ostream_joiner(ostream_type& __os, const _Delim& __d)
      : __output_iter_(std::addressof(__os)), __delim_(__d), __first_(true) {}

  template <typename _Tp>
  _LIBCPP_HIDE_FROM_ABI ostream_joiner& operator=(const _Tp& __v) {
    if (!__first_)
      *__output_iter_ << __delim_;
    __first_ = false;
    *__output_iter_ << __v;
    return *this;
  }

  _LIBCPP_HIDE_FROM_ABI ostream_joiner& operator*() _NOEXCEPT { return *this; }
  _LIBCPP_HIDE_FROM_ABI ostream_joiner& operator++() _NOEXCEPT { return *this; }
  _LIBCPP_HIDE_FROM_ABI ostream_joiner& operator++(int) _NOEXCEPT { return *this; }

private:
  ostream_type* __output_iter_;
  _Delim __delim_;
  bool __first_;
};

template <class _CharT, class _Traits, class _Delim>
_LIBCPP_HIDE_FROM_ABI ostream_joiner<__decay_t<_Delim>, _CharT, _Traits>
make_ostream_joiner(basic_ostream<_CharT, _Traits>& __os, _Delim&& __d) {
  return ostream_joiner<__decay_t<_Delim>, _CharT, _Traits>(__os, std::forward<_Delim>(__d));
}

_LIBCPP_END_NAMESPACE_LFTS

#endif // _LIBCPP_STD_VER >= 14

_LIBCPP_POP_MACROS

#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
#  include <iosfwd>
#  include <type_traits>
#endif

#endif // _LIBCPP_EXPERIMENTAL_ITERATOR