xref: /freebsd-src/contrib/llvm-project/libcxx/include/__iterator/istream_iterator.h (revision e67e85659c0de33e617e5fbf1028c6e8b49eee53)
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 <__iterator/iterator.h>
15 #include <__iterator/iterator_traits.h>
16 #include <__memory/addressof.h>
17 #include <iosfwd> // for forward declarations of char_traits and basic_istream
18 
19 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
20 #pragma GCC system_header
21 #endif
22 
23 _LIBCPP_BEGIN_NAMESPACE_STD
24 
25 _LIBCPP_SUPPRESS_DEPRECATED_PUSH
26 template <class _Tp, class _CharT = char,
27           class _Traits = char_traits<_CharT>, class _Distance = ptrdiff_t>
28 class _LIBCPP_TEMPLATE_VIS istream_iterator
29 #if _LIBCPP_STD_VER <= 14 || !defined(_LIBCPP_ABI_NO_ITERATOR_BASES)
30     : public iterator<input_iterator_tag, _Tp, _Distance, const _Tp*, const _Tp&>
31 #endif
32 {
33 _LIBCPP_SUPPRESS_DEPRECATED_POP
34 public:
35     typedef input_iterator_tag iterator_category;
36     typedef _Tp value_type;
37     typedef _Distance difference_type;
38     typedef const _Tp* pointer;
39     typedef const _Tp& reference;
40     typedef _CharT char_type;
41     typedef _Traits traits_type;
42     typedef basic_istream<_CharT,_Traits> istream_type;
43 private:
44     istream_type* __in_stream_;
45     _Tp __value_;
46 public:
47     _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR istream_iterator() : __in_stream_(nullptr), __value_() {}
48     _LIBCPP_INLINE_VISIBILITY istream_iterator(istream_type& __s) : __in_stream_(_VSTD::addressof(__s))
49         {
50             if (!(*__in_stream_ >> __value_))
51                 __in_stream_ = nullptr;
52         }
53 
54     _LIBCPP_INLINE_VISIBILITY const _Tp& operator*() const {return __value_;}
55     _LIBCPP_INLINE_VISIBILITY const _Tp* operator->() const {return _VSTD::addressof((operator*()));}
56     _LIBCPP_INLINE_VISIBILITY istream_iterator& operator++()
57         {
58             if (!(*__in_stream_ >> __value_))
59                 __in_stream_ = nullptr;
60             return *this;
61         }
62     _LIBCPP_INLINE_VISIBILITY istream_iterator  operator++(int)
63         {istream_iterator __t(*this); ++(*this); return __t;}
64 
65     template <class _Up, class _CharU, class _TraitsU, class _DistanceU>
66     friend _LIBCPP_INLINE_VISIBILITY
67     bool
68     operator==(const istream_iterator<_Up, _CharU, _TraitsU, _DistanceU>& __x,
69                const istream_iterator<_Up, _CharU, _TraitsU, _DistanceU>& __y);
70 };
71 
72 template <class _Tp, class _CharT, class _Traits, class _Distance>
73 inline _LIBCPP_INLINE_VISIBILITY
74 bool
75 operator==(const istream_iterator<_Tp, _CharT, _Traits, _Distance>& __x,
76            const istream_iterator<_Tp, _CharT, _Traits, _Distance>& __y)
77 {
78     return __x.__in_stream_ == __y.__in_stream_;
79 }
80 
81 template <class _Tp, class _CharT, class _Traits, class _Distance>
82 inline _LIBCPP_INLINE_VISIBILITY
83 bool
84 operator!=(const istream_iterator<_Tp, _CharT, _Traits, _Distance>& __x,
85            const istream_iterator<_Tp, _CharT, _Traits, _Distance>& __y)
86 {
87     return !(__x == __y);
88 }
89 
90 _LIBCPP_END_NAMESPACE_STD
91 
92 #endif // _LIBCPP___ITERATOR_ISTREAM_ITERATOR_H
93