xref: /openbsd-src/gnu/lib/libstdc++/libstdc++/include/bits/stream_iterator.h (revision 03a78d155d6fff5698289342b62759a75b20d130)
1 // Stream iterators
2 
3 // Copyright (C) 2001 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 2, 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 // You should have received a copy of the GNU General Public License along
17 // with this library; see the file COPYING.  If not, write to the Free
18 // Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
19 // USA.
20 
21 // As a special exception, you may use this file as part of a free software
22 // library without restriction.  Specifically, if other files instantiate
23 // templates or use macros or inline functions from this file, or you compile
24 // this file and link it with other files to produce an executable, this
25 // file does not by itself cause the resulting executable to be covered by
26 // the GNU General Public License.  This exception does not however
27 // invalidate any other reasons why the executable file might be covered by
28 // the GNU General Public License.
29 
30 /** @file stream_iterator.h
31  *  This is an internal header file, included by other library headers.
32  *  You should not attempt to use it directly.
33  */
34 
35 #ifndef _CPP_BITS_STREAM_ITERATOR_H
36 #define _CPP_BITS_STREAM_ITERATOR_H 1
37 
38 #pragma GCC system_header
39 
40 namespace std
41 {
42   template<typename _Tp, typename _CharT = char,
43            typename _Traits = char_traits<_CharT>, typename _Dist = ptrdiff_t>
44     class istream_iterator
45       : public iterator<input_iterator_tag, _Tp, _Dist, const _Tp*, const _Tp&>
46     {
47     public:
48       typedef _CharT                         char_type;
49       typedef _Traits                        traits_type;
50       typedef basic_istream<_CharT, _Traits> istream_type;
51 
52     private:
53       istream_type* 	_M_stream;
54       _Tp 		_M_value;
55       bool 		_M_ok;
56 
57     public:
istream_iterator()58       istream_iterator() : _M_stream(0), _M_ok(false) {}
59 
istream_iterator(istream_type & __s)60       istream_iterator(istream_type& __s) : _M_stream(&__s) { _M_read(); }
61 
istream_iterator(const istream_iterator & __obj)62       istream_iterator(const istream_iterator& __obj)
63       : _M_stream(__obj._M_stream), _M_value(__obj._M_value),
64         _M_ok(__obj._M_ok)
65       { }
66 
67       const _Tp&
68       operator*() const { return _M_value; }
69 
70       const _Tp*
71       operator->() const { return &(operator*()); }
72 
73       istream_iterator&
74       operator++()
75       { _M_read(); return *this; }
76 
77       istream_iterator
78       operator++(int)
79       {
80 	istream_iterator __tmp = *this;
81 	_M_read();
82 	return __tmp;
83       }
84 
85       bool
_M_equal(const istream_iterator & __x)86       _M_equal(const istream_iterator& __x) const
87       { return (_M_ok == __x._M_ok) && (!_M_ok || _M_stream == __x._M_stream);}
88 
89     private:
90       void
_M_read()91       _M_read()
92       {
93 	_M_ok = (_M_stream && *_M_stream) ? true : false;
94 	if (_M_ok)
95 	  {
96 	    *_M_stream >> _M_value;
97 	    _M_ok = *_M_stream ? true : false;
98 	  }
99       }
100     };
101 
102   template<typename _Tp, typename _CharT, typename _Traits, typename _Dist>
103     inline bool
104     operator==(const istream_iterator<_Tp, _CharT, _Traits, _Dist>& __x,
105 	       const istream_iterator<_Tp, _CharT, _Traits, _Dist>& __y)
106     { return __x._M_equal(__y); }
107 
108   template <class _Tp, class _CharT, class _Traits, class _Dist>
109     inline bool
110     operator!=(const istream_iterator<_Tp, _CharT, _Traits, _Dist>& __x,
111 	       const istream_iterator<_Tp, _CharT, _Traits, _Dist>& __y)
112     { return !__x._M_equal(__y); }
113 
114 
115   template<typename _Tp, typename _CharT = char,
116            typename _Traits = char_traits<_CharT> >
117     class ostream_iterator
118       : public iterator<output_iterator_tag, void, void, void, void>
119     {
120     public:
121       typedef _CharT                         char_type;
122       typedef _Traits                        traits_type;
123       typedef basic_ostream<_CharT, _Traits> ostream_type;
124 
125     private:
126       ostream_type* 	_M_stream;
127       const _CharT* 	_M_string;
128 
129     public:
ostream_iterator(ostream_type & __s)130       ostream_iterator(ostream_type& __s) : _M_stream(&__s), _M_string(0) {}
131 
ostream_iterator(ostream_type & __s,const _CharT * __c)132       ostream_iterator(ostream_type& __s, const _CharT* __c)
133       : _M_stream(&__s), _M_string(__c)  { }
134 
ostream_iterator(const ostream_iterator & __obj)135       ostream_iterator(const ostream_iterator& __obj)
136       : _M_stream(__obj._M_stream), _M_string(__obj._M_string)  { }
137 
138       ostream_iterator&
139       operator=(const _Tp& __value)
140       {
141 	*_M_stream << __value;
142 	if (_M_string) *_M_stream << _M_string;
143 	return *this;
144       }
145 
146       ostream_iterator&
147       operator*() { return *this; }
148 
149       ostream_iterator&
150       operator++() { return *this; }
151 
152       ostream_iterator&
153       operator++(int) { return *this; }
154     };
155 } // namespace std
156 #endif
157