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 <__cstddef/ptrdiff_t.h>
15#include <__fwd/istream.h>
16#include <__fwd/string.h>
17#include <__iterator/default_sentinel.h>
18#include <__iterator/iterator.h>
19#include <__iterator/iterator_traits.h>
20#include <__memory/addressof.h>
21
22#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
23# pragma GCC system_header
24#endif
25
26_LIBCPP_BEGIN_NAMESPACE_STD
27
28template <class _Tp, class _CharT = char, class _Traits = char_traits<_CharT>, class _Distance = ptrdiff_t>
29class istream_iterator
30 : public __iterator_base<istream_iterator<_Tp, _CharT, _Traits, _Distance>,
31 input_iterator_tag,
32 _Tp,
33 _Distance,
34 const _Tp*,
35 const _Tp&> {
36public:
37 typedef input_iterator_tag iterator_category;
38 typedef _Tp value_type;
39 typedef _Distance difference_type;
40 typedef const _Tp* pointer;
41 typedef const _Tp& reference;
42 typedef _CharT char_type;
43 typedef _Traits traits_type;
44 typedef basic_istream<_CharT, _Traits> istream_type;
45
46private:
47 istream_type* __in_stream_;
48 _Tp __value_;
49
50public:
51 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR istream_iterator() : __in_stream_(nullptr), __value_() {}
52#if _LIBCPP_STD_VER >= 20
53 _LIBCPP_HIDE_FROM_ABI constexpr istream_iterator(default_sentinel_t) : istream_iterator() {}
54#endif // _LIBCPP_STD_VER >= 20
55 _LIBCPP_HIDE_FROM_ABI istream_iterator(istream_type& __s) : __in_stream_(std::addressof(__s)) {
56 if (!(*__in_stream_ >> __value_))
57 __in_stream_ = nullptr;
58 }
59
60 // LWG3600 Changed the wording of the copy constructor. In libc++ this constructor
61 // can still be trivial after this change.
62
63 _LIBCPP_HIDE_FROM_ABI const _Tp& operator*() const { return __value_; }
64 _LIBCPP_HIDE_FROM_ABI const _Tp* operator->() const { return std::addressof((operator*())); }
65 _LIBCPP_HIDE_FROM_ABI istream_iterator& operator++() {
66 if (!(*__in_stream_ >> __value_))
67 __in_stream_ = nullptr;
68 return *this;
69 }
70 _LIBCPP_HIDE_FROM_ABI istream_iterator operator++(int) {
71 istream_iterator __t(*this);
72 ++(*this);
73 return __t;
74 }
75
76 template <class _Up, class _CharU, class _TraitsU, class _DistanceU>
77 friend _LIBCPP_HIDE_FROM_ABI bool operator==(const istream_iterator<_Up, _CharU, _TraitsU, _DistanceU>& __x,
78 const istream_iterator<_Up, _CharU, _TraitsU, _DistanceU>& __y);
79
80#if _LIBCPP_STD_VER >= 20
81 friend _LIBCPP_HIDE_FROM_ABI bool operator==(const istream_iterator& __i, default_sentinel_t) {
82 return __i.__in_stream_ == nullptr;
83 }
84#endif // _LIBCPP_STD_VER >= 20
85};
86
87template <class _Tp, class _CharT, class _Traits, class _Distance>
88inline _LIBCPP_HIDE_FROM_ABI bool operator==(const istream_iterator<_Tp, _CharT, _Traits, _Distance>& __x,
89 const istream_iterator<_Tp, _CharT, _Traits, _Distance>& __y) {
90 return __x.__in_stream_ == __y.__in_stream_;
91}
92
93#if _LIBCPP_STD_VER <= 17
94template <class _Tp, class _CharT, class _Traits, class _Distance>
95inline _LIBCPP_HIDE_FROM_ABI bool operator!=(const istream_iterator<_Tp, _CharT, _Traits, _Distance>& __x,
96 const istream_iterator<_Tp, _CharT, _Traits, _Distance>& __y) {
97 return !(__x == __y);
98}
99#endif // _LIBCPP_STD_VER <= 17
100
101_LIBCPP_END_NAMESPACE_STD
102
103#endif // _LIBCPP___ITERATOR_ISTREAM_ITERATOR_H
104