libcxx/include/experimental/iterator

   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 /*
  14 namespace 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 <__type_traits/decay.h>
  58 #include <__utility/forward.h>
  59 #include <__utility/move.h>
  60 #include <experimental/__config>
  61 #include <iterator>
  62
  63 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
  64 #  pragma GCC system_header
  65 #endif
  66
  67 _LIBCPP_PUSH_MACROS
  68 #include <__undef_macros>
  69
  70 #if _LIBCPP_STD_VER >= 14
  71
  72 _LIBCPP_BEGIN_NAMESPACE_LFTS
  73
  74 template <class _Delim, class _CharT = char, class _Traits = char_traits<_CharT>>
  75 class ostream_joiner {
  76 public:
  77   typedef _CharT char_type;
  78   typedef _Traits traits_type;
  79   typedef basic_ostream<char_type, traits_type> ostream_type;
  80   typedef output_iterator_tag iterator_category;
  81   typedef void value_type;
  82   typedef void difference_type;
  83   typedef void pointer;
  84   typedef void reference;
  85
  86   _LIBCPP_HIDE_FROM_ABI ostream_joiner(ostream_type& __os, _Delim&& __d)
  87       : __output_iter_(std::addressof(__os)), __delim_(std::move(__d)), __first_(true) {}
  88
  89   _LIBCPP_HIDE_FROM_ABI ostream_joiner(ostream_type& __os, const _Delim& __d)
  90       : __output_iter_(std::addressof(__os)), __delim_(__d), __first_(true) {}
  91
  92   template <typename _Tp>
  93   _LIBCPP_HIDE_FROM_ABI ostream_joiner& operator=(const _Tp& __v) {
  94     if (!__first_)
  95       *__output_iter_ << __delim_;
  96     __first_ = false;
  97     *__output_iter_ << __v;
  98     return *this;
  99   }
 100
 101   _LIBCPP_HIDE_FROM_ABI ostream_joiner& operator*() _NOEXCEPT { return *this; }
 102   _LIBCPP_HIDE_FROM_ABI ostream_joiner& operator++() _NOEXCEPT { return *this; }
 103   _LIBCPP_HIDE_FROM_ABI ostream_joiner& operator++(int) _NOEXCEPT { return *this; }
 104
 105 private:
 106   ostream_type* __output_iter_;
 107   _Delim __delim_;
 108   bool __first_;
 109 };
 110
 111 template <class _CharT, class _Traits, class _Delim>
 112 _LIBCPP_HIDE_FROM_ABI ostream_joiner<__decay_t<_Delim>, _CharT, _Traits>
 113 make_ostream_joiner(basic_ostream<_CharT, _Traits>& __os, _Delim&& __d) {
 114   return ostream_joiner<__decay_t<_Delim>, _CharT, _Traits>(__os, std::forward<_Delim>(__d));
 115 }
 116
 117 _LIBCPP_END_NAMESPACE_LFTS
 118
 119 #endif // _LIBCPP_STD_VER >= 14
 120
 121 _LIBCPP_POP_MACROS
 122
 123 #if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
 124 #  include <iosfwd>
 125 #  include <type_traits>
 126 #endif
 127
 128 #endif // _LIBCPP_EXPERIMENTAL_ITERATOR