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___ITERATOR_ISTREAM_ITERATOR_H
11 #define _LIBCPP___ITERATOR_ISTREAM_ITERATOR_H
12 
13 #include <__config>
14 #include <__fwd/istream.h>
15 #include <__fwd/string.h>
16 #include <__iterator/default_sentinel.h>
17 #include <__iterator/iterator.h>
18 #include <__iterator/iterator_traits.h>
19 #include <__memory/addressof.h>
20 #include <cstddef>
21 
22 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
23 #  pragma GCC system_header
24 #endif
25 
26 _LIBCPP_BEGIN_NAMESPACE_STD
27 
28 _LIBCPP_SUPPRESS_DEPRECATED_PUSH
29 template <class _Tp, class _CharT = char, class _Traits = char_traits<_CharT>, class _Distance = ptrdiff_t>
30 class _LIBCPP_TEMPLATE_VIS istream_iterator
31 #if _LIBCPP_STD_VER <= 14 || !defined(_LIBCPP_ABI_NO_ITERATOR_BASES)
32     : public iterator<input_iterator_tag, _Tp, _Distance, const _Tp*, const _Tp&>
33 #endif
34 {
35   _LIBCPP_SUPPRESS_DEPRECATED_POP
36 
37 public:
38   typedef input_iterator_tag iterator_category;
39   typedef _Tp value_type;
40   typedef _Distance difference_type;
41   typedef const _Tp* pointer;
42   typedef const _Tp& reference;
43   typedef _CharT char_type;
44   typedef _Traits traits_type;
45   typedef basic_istream<_CharT, _Traits> istream_type;
46 
47 private:
48   istream_type* __in_stream_;
49   _Tp __value_;
50 
51 public:
52   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR istream_iterator() : __in_stream_(nullptr), __value_() {}
53 #if _LIBCPP_STD_VER >= 20
54   _LIBCPP_HIDE_FROM_ABI constexpr istream_iterator(default_sentinel_t) : istream_iterator() {}
55 #endif // _LIBCPP_STD_VER >= 20
56   _LIBCPP_HIDE_FROM_ABI istream_iterator(istream_type& __s) : __in_stream_(std::addressof(__s)) {
57     if (!(*__in_stream_ >> __value_))
58       __in_stream_ = nullptr;
59   }
60 
61   _LIBCPP_HIDE_FROM_ABI const _Tp& operator*() const { return __value_; }
62   _LIBCPP_HIDE_FROM_ABI const _Tp* operator->() const { return std::addressof((operator*())); }
63   _LIBCPP_HIDE_FROM_ABI istream_iterator& operator++() {
64     if (!(*__in_stream_ >> __value_))
65       __in_stream_ = nullptr;
66     return *this;
67   }
68   _LIBCPP_HIDE_FROM_ABI istream_iterator operator++(int) {
69     istream_iterator __t(*this);
70     ++(*this);
71     return __t;
72   }
73 
74   template <class _Up, class _CharU, class _TraitsU, class _DistanceU>
75   friend _LIBCPP_HIDE_FROM_ABI bool operator==(const istream_iterator<_Up, _CharU, _TraitsU, _DistanceU>& __x,
76                                                const istream_iterator<_Up, _CharU, _TraitsU, _DistanceU>& __y);
77 
78 #if _LIBCPP_STD_VER >= 20
79   friend _LIBCPP_HIDE_FROM_ABI bool operator==(const istream_iterator& __i, default_sentinel_t) {
80     return __i.__in_stream_ == nullptr;
81   }
82 #endif // _LIBCPP_STD_VER >= 20
83 };
84 
85 template <class _Tp, class _CharT, class _Traits, class _Distance>
86 inline _LIBCPP_HIDE_FROM_ABI bool operator==(const istream_iterator<_Tp, _CharT, _Traits, _Distance>& __x,
87                                              const istream_iterator<_Tp, _CharT, _Traits, _Distance>& __y) {
88   return __x.__in_stream_ == __y.__in_stream_;
89 }
90 
91 #if _LIBCPP_STD_VER <= 17
92 template <class _Tp, class _CharT, class _Traits, class _Distance>
93 inline _LIBCPP_HIDE_FROM_ABI bool operator!=(const istream_iterator<_Tp, _CharT, _Traits, _Distance>& __x,
94                                              const istream_iterator<_Tp, _CharT, _Traits, _Distance>& __y) {
95   return !(__x == __y);
96 }
97 #endif // _LIBCPP_STD_VER <= 17
98 
99 _LIBCPP_END_NAMESPACE_STD
100 
101 #endif // _LIBCPP___ITERATOR_ISTREAM_ITERATOR_H
102