1// -*- C++ -*-
2//===----------------------------------------------------------------------===//
3//
4// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5// See https://llvm.org/LICENSE.txt for license information.
6// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7//
8//===----------------------------------------------------------------------===//
9
10#ifndef _LIBCPP_EXPERIMENTAL_ITERATOR
11#define _LIBCPP_EXPERIMENTAL_ITERATOR
12
13/*
14namespace std {
15  namespace experimental {
16    inline namespace fundamentals_v2 {
17
18    template <class DelimT, class charT = char, class traits = char_traits<charT>>
19        class ostream_joiner {
20        public:
21         typedef charT                        char_type;
22         typedef traits                       traits_type;
23         typedef basic_ostream<charT, traits> ostream_type;
24         typedef output_iterator_tag          iterator_category;
25         typedef void                         value_type;
26         typedef void                         difference_type;
27         typedef void                         pointer;
28         typedef void                         reference;
29
30         ostream_joiner(ostream_type& s, const DelimT& delimiter);
31         ostream_joiner(ostream_type& s, DelimT&& delimiter);
32
33         template<typename T>
34         ostream_joiner& operator=(const T& value);
35
36         ostream_joiner& operator*() noexcept;
37         ostream_joiner& operator++() noexcept;
38         ostream_joiner& operator++(int) noexcept;
39   private:
40      ostream_type* out_stream;   // exposition only
41      DelimT delim;               // exposition only
42      bool first_element;         // exposition only
43   };
44
45  template <class charT, class traits, class DelimT>
46    ostream_joiner<decay_t<DelimT>, charT, traits>
47    make_ostream_joiner(basic_ostream<charT, traits>& os, DelimT&& delimiter);
48
49    } // inline namespace fundamentals_v2
50  } // namespace experimental
51} // namespace std
52
53*/
54
55#include <__assert> // all public C++ headers provide the assertion handler
56#include <__memory/addressof.h>
57#include <__utility/forward.h>
58#include <__utility/move.h>
59#include <experimental/__config>
60#include <iosfwd> // char_traits
61#include <iterator>
62
63#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
64#  pragma GCC system_header
65#endif
66
67#if _LIBCPP_STD_VER > 11
68
69_LIBCPP_BEGIN_NAMESPACE_LFTS
70
71template <class _Delim, class _CharT = char, class _Traits = char_traits<_CharT>>
72class ostream_joiner {
73public:
74
75    typedef _CharT                               char_type;
76    typedef _Traits                              traits_type;
77    typedef basic_ostream<char_type,traits_type> ostream_type;
78    typedef output_iterator_tag                  iterator_category;
79    typedef void                                 value_type;
80    typedef void                                 difference_type;
81    typedef void                                 pointer;
82    typedef void                                 reference;
83
84    ostream_joiner(ostream_type& __os, _Delim&& __d)
85        : __output_iter(_VSTD::addressof(__os)), __delim(_VSTD::move(__d)), __first(true) {}
86
87    ostream_joiner(ostream_type& __os, const _Delim& __d)
88        : __output_iter(_VSTD::addressof(__os)), __delim(__d), __first(true) {}
89
90
91    template<typename _Tp>
92    ostream_joiner& operator=(const _Tp& __v)
93    {
94        if (!__first)
95            *__output_iter << __delim;
96        __first = false;
97        *__output_iter << __v;
98        return *this;
99    }
100
101    ostream_joiner& operator*()     _NOEXCEPT { return *this; }
102    ostream_joiner& operator++()    _NOEXCEPT { return *this; }
103    ostream_joiner& operator++(int) _NOEXCEPT { return *this; }
104
105private:
106    ostream_type*   __output_iter;
107    _Delim          __delim;
108    bool            __first;
109};
110
111
112template <class _CharT, class _Traits, class _Delim>
113ostream_joiner<typename decay<_Delim>::type, _CharT, _Traits>
114make_ostream_joiner(basic_ostream<_CharT, _Traits>& __os, _Delim && __d)
115{ return ostream_joiner<typename decay<_Delim>::type, _CharT, _Traits>(__os, _VSTD::forward<_Delim>(__d)); }
116
117_LIBCPP_END_NAMESPACE_LFTS
118
119#endif // _LIBCPP_STD_VER > 11
120
121#endif // _LIBCPP_EXPERIMENTAL_ITERATOR
122