include/experimental/iterator

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

#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 <experimental/__config>

#if _LIBCPP_STD_VER > 11

#include <iterator>

_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;

 ostream_joiner(ostream_type& __os, _Delim&& __d)
 : __output_iter(_VSTD::addressof(__os)), __delim(_VSTD::move(__d)), __first(true) {}
 
 ostream_joiner(ostream_type& __os, const _Delim& __d)
 : __output_iter(_VSTD::addressof(__os)), __delim(__d), __first(true) {}
 

 template<typename _Tp>
 ostream_joiner& operator=(const _Tp& __v)
 {
 if (!__first)
 *__output_iter << __delim;
 __first = false;
 *__output_iter << __v;
 return *this;
 }

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

private:
 ostream_type* __output_iter;
 _Delim __delim;
 bool __first;
};


template <class _CharT, class _Traits, class _Delim>
ostream_joiner<typename decay<_Delim>::type, _CharT, _Traits>
make_ostream_joiner(basic_ostream<_CharT, _Traits>& __os, _Delim && __d)
{ return ostream_joiner<typename decay<_Delim>::type, _CharT, _Traits>(__os, _VSTD::forward<_Delim>(__d)); }

_LIBCPP_END_NAMESPACE_LFTS

#endif /* _LIBCPP_STD_VER > 11 */

#endif // _LIBCPP_EXPERIMENTAL_ITERATOR