1 | // Boost string_algo library compare.hpp header file -------------------------// |
2 | |
3 | // Copyright Pavol Droba 2002-2006. |
4 | // |
5 | // Distributed under the Boost Software License, Version 1.0. |
6 | // (See accompanying file LICENSE_1_0.txt or copy at |
7 | // http://www.boost.org/LICENSE_1_0.txt) |
8 | |
9 | // See http://www.boost.org/ for updates, documentation, and revision history. |
10 | |
11 | #ifndef BOOST_STRING_COMPARE_HPP |
12 | #define BOOST_STRING_COMPARE_HPP |
13 | |
14 | #include <boost/algorithm/string/config.hpp> |
15 | #include <locale> |
16 | |
17 | /*! \file |
18 | Defines element comparison predicates. Many algorithms in this library can |
19 | take an additional argument with a predicate used to compare elements. |
20 | This makes it possible, for instance, to have case insensitive versions |
21 | of the algorithms. |
22 | */ |
23 | |
24 | namespace boost { |
25 | namespace algorithm { |
26 | |
27 | // is_equal functor -----------------------------------------------// |
28 | |
29 | //! is_equal functor |
30 | /*! |
31 | Standard STL equal_to only handle comparison between arguments |
32 | of the same type. This is a less restrictive version which wraps operator ==. |
33 | */ |
34 | struct is_equal |
35 | { |
36 | //! Function operator |
37 | /*! |
38 | Compare two operands for equality |
39 | */ |
40 | template< typename T1, typename T2 > |
41 | bool operator()( const T1& Arg1, const T2& Arg2 ) const |
42 | { |
43 | return Arg1==Arg2; |
44 | } |
45 | }; |
46 | |
47 | //! case insensitive version of is_equal |
48 | /*! |
49 | Case insensitive comparison predicate. Comparison is done using |
50 | specified locales. |
51 | */ |
52 | struct is_iequal |
53 | { |
54 | //! Constructor |
55 | /*! |
56 | \param Loc locales used for comparison |
57 | */ |
58 | is_iequal( const std::locale& Loc=std::locale() ) : |
59 | m_Loc( Loc ) {} |
60 | |
61 | //! Function operator |
62 | /*! |
63 | Compare two operands. Case is ignored. |
64 | */ |
65 | template< typename T1, typename T2 > |
66 | bool operator()( const T1& Arg1, const T2& Arg2 ) const |
67 | { |
68 | #if defined(BOOST_BORLANDC) && (BOOST_BORLANDC >= 0x560) && (BOOST_BORLANDC <= 0x564) && !defined(_USE_OLD_RW_STL) |
69 | return std::toupper(Arg1)==std::toupper(Arg2); |
70 | #else |
71 | return std::toupper<T1>(Arg1,m_Loc)==std::toupper<T2>(Arg2,m_Loc); |
72 | #endif |
73 | } |
74 | |
75 | private: |
76 | std::locale m_Loc; |
77 | }; |
78 | |
79 | // is_less functor -----------------------------------------------// |
80 | |
81 | //! is_less functor |
82 | /*! |
83 | Convenient version of standard std::less. Operation is templated, therefore it is |
84 | not required to specify the exact types upon the construction |
85 | */ |
86 | struct is_less |
87 | { |
88 | //! Functor operation |
89 | /*! |
90 | Compare two operands using > operator |
91 | */ |
92 | template< typename T1, typename T2 > |
93 | bool operator()( const T1& Arg1, const T2& Arg2 ) const |
94 | { |
95 | return Arg1<Arg2; |
96 | } |
97 | }; |
98 | |
99 | |
100 | //! case insensitive version of is_less |
101 | /*! |
102 | Case insensitive comparison predicate. Comparison is done using |
103 | specified locales. |
104 | */ |
105 | struct is_iless |
106 | { |
107 | //! Constructor |
108 | /*! |
109 | \param Loc locales used for comparison |
110 | */ |
111 | is_iless( const std::locale& Loc=std::locale() ) : |
112 | m_Loc( Loc ) {} |
113 | |
114 | //! Function operator |
115 | /*! |
116 | Compare two operands. Case is ignored. |
117 | */ |
118 | template< typename T1, typename T2 > |
119 | bool operator()( const T1& Arg1, const T2& Arg2 ) const |
120 | { |
121 | #if defined(BOOST_BORLANDC) && (BOOST_BORLANDC >= 0x560) && (BOOST_BORLANDC <= 0x564) && !defined(_USE_OLD_RW_STL) |
122 | return std::toupper(Arg1)<std::toupper(Arg2); |
123 | #else |
124 | return std::toupper<T1>(Arg1,m_Loc)<std::toupper<T2>(Arg2,m_Loc); |
125 | #endif |
126 | } |
127 | |
128 | private: |
129 | std::locale m_Loc; |
130 | }; |
131 | |
132 | // is_not_greater functor -----------------------------------------------// |
133 | |
134 | //! is_not_greater functor |
135 | /*! |
136 | Convenient version of standard std::not_greater_to. Operation is templated, therefore it is |
137 | not required to specify the exact types upon the construction |
138 | */ |
139 | struct is_not_greater |
140 | { |
141 | //! Functor operation |
142 | /*! |
143 | Compare two operands using > operator |
144 | */ |
145 | template< typename T1, typename T2 > |
146 | bool operator()( const T1& Arg1, const T2& Arg2 ) const |
147 | { |
148 | return Arg1<=Arg2; |
149 | } |
150 | }; |
151 | |
152 | |
153 | //! case insensitive version of is_not_greater |
154 | /*! |
155 | Case insensitive comparison predicate. Comparison is done using |
156 | specified locales. |
157 | */ |
158 | struct is_not_igreater |
159 | { |
160 | //! Constructor |
161 | /*! |
162 | \param Loc locales used for comparison |
163 | */ |
164 | is_not_igreater( const std::locale& Loc=std::locale() ) : |
165 | m_Loc( Loc ) {} |
166 | |
167 | //! Function operator |
168 | /*! |
169 | Compare two operands. Case is ignored. |
170 | */ |
171 | template< typename T1, typename T2 > |
172 | bool operator()( const T1& Arg1, const T2& Arg2 ) const |
173 | { |
174 | #if defined(BOOST_BORLANDC) && (BOOST_BORLANDC >= 0x560) && (BOOST_BORLANDC <= 0x564) && !defined(_USE_OLD_RW_STL) |
175 | return std::toupper(Arg1)<=std::toupper(Arg2); |
176 | #else |
177 | return std::toupper<T1>(Arg1,m_Loc)<=std::toupper<T2>(Arg2,m_Loc); |
178 | #endif |
179 | } |
180 | |
181 | private: |
182 | std::locale m_Loc; |
183 | }; |
184 | |
185 | |
186 | } // namespace algorithm |
187 | |
188 | // pull names to the boost namespace |
189 | using algorithm::is_equal; |
190 | using algorithm::is_iequal; |
191 | using algorithm::is_less; |
192 | using algorithm::is_iless; |
193 | using algorithm::is_not_greater; |
194 | using algorithm::is_not_igreater; |
195 | |
196 | } // namespace boost |
197 | |
198 | |
199 | #endif // BOOST_STRING_COMPARE_HPP |
200 | |