libstdc++
experimental/iterator
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1 // <experimental/iterator> -*- C++ -*-
2 
3 // Copyright (C) 2015-2016 Free Software Foundation, Inc.
4 //
5 // This file is part of the GNU ISO C++ Library. This library is free
6 // software; you can redistribute it and/or modify it under the
7 // terms of the GNU General Public License as published by the
8 // Free Software Foundation; either version 3, or (at your option)
9 // any later version.
10 
11 // This library is distributed in the hope that it will be useful,
12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 // GNU General Public License for more details.
15 
16 // Under Section 7 of GPL version 3, you are granted additional
17 // permissions described in the GCC Runtime Library Exception, version
18 // 3.1, as published by the Free Software Foundation.
19 
20 // You should have received a copy of the GNU General Public License and
21 // a copy of the GCC Runtime Library Exception along with this program;
22 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23 // <http://www.gnu.org/licenses/>.
24 
25 /** @file experimental/iterator
26  * This is a TS C++ Library header.
27  */
28 
29 //
30 // N4336 Working Draft, C++ Extensions for Library Fundamentals, Version 2
31 //
32 
33 #ifndef _GLIBCXX_EXPERIMENTAL_ITERATOR
34 #define _GLIBCXX_EXPERIMENTAL_ITERATOR 1
35 
36 #pragma GCC system_header
37 
38 #if __cplusplus <= 201103L
39 # include <bits/c++14_warning.h>
40 #else
41 
42 #include <experimental/type_traits>
43 #include <iosfwd>
44 #include <bits/move.h>
45 #include <bits/stl_iterator_base_types.h>
46 
47 namespace std _GLIBCXX_VISIBILITY(default)
48 {
49 namespace experimental
50 {
51 inline namespace fundamentals_v2
52 {
53 _GLIBCXX_BEGIN_NAMESPACE_VERSION
54 
55 #define __cpp_lib_experimental_ostream_joiner 201411
56 
57  /// Output iterator that inserts a delimiter between elements.
58  template<typename _DelimT, typename _CharT = char,
59  typename _Traits = char_traits<_CharT>>
60  class ostream_joiner
61  {
62  public:
63  typedef _CharT char_type;
64  typedef _Traits traits_type;
65  typedef basic_ostream<_CharT, _Traits> ostream_type;
66  typedef output_iterator_tag iterator_category;
67  typedef void value_type;
68  typedef void difference_type;
69  typedef void pointer;
70  typedef void reference;
71 
72  ostream_joiner(ostream_type& __os, const _DelimT& __delimiter)
73  noexcept(is_nothrow_copy_constructible_v<_DelimT>)
74  : _M_out(std::__addressof(__os)), _M_delim(__delimiter)
75  { }
76 
77  ostream_joiner(ostream_type& __os, _DelimT&& __delimiter)
78  noexcept(is_nothrow_move_constructible_v<_DelimT>)
79  : _M_out(std::__addressof(__os)), _M_delim(std::move(__delimiter))
80  { }
81 
82  template<typename _Tp>
83  ostream_joiner&
84  operator=(const _Tp& __value)
85  {
86  if (!_M_first)
87  *_M_out << _M_delim;
88  _M_first = false;
89  *_M_out << __value;
90  return *this;
91  }
92 
93  ostream_joiner& operator*() noexcept { return *this; }
94  ostream_joiner& operator++() noexcept { return *this; }
95  ostream_joiner& operator++(int) noexcept { return *this; }
96 
97  private:
98  ostream_type* _M_out;
99  _DelimT _M_delim;
100  bool _M_first = true;
101  };
102 
103  /// Object generator for ostream_joiner.
104  template<typename _CharT, typename _Traits, typename _DelimT>
105  inline ostream_joiner<decay_t<_DelimT>, _CharT, _Traits>
106  make_ostream_joiner(basic_ostream<_CharT, _Traits>& __os,
107  _DelimT&& __delimiter)
108  { return { __os, std::forward<_DelimT>(__delimiter) }; }
109 
110 _GLIBCXX_END_NAMESPACE_VERSION
111 } // namespace fundamentals_v2
112 } // namespace experimental
113 } // namespace std
114 
115 #endif // __cplusplus <= 201103L
116 
117 #endif // _GLIBCXX_EXPERIMENTAL_ITERATOR