1 | /* |
2 | * Copyright (c) 2017, Intel Corporation |
3 | * |
4 | * Redistribution and use in source and binary forms, with or without |
5 | * modification, are permitted provided that the following conditions are met: |
6 | * |
7 | * * Redistributions of source code must retain the above copyright notice, |
8 | * this list of conditions and the following disclaimer. |
9 | * * Redistributions in binary form must reproduce the above copyright |
10 | * notice, this list of conditions and the following disclaimer in the |
11 | * documentation and/or other materials provided with the distribution. |
12 | * * Neither the name of Intel Corporation nor the names of its contributors |
13 | * may be used to endorse or promote products derived from this software |
14 | * without specific prior written permission. |
15 | * |
16 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" |
17 | * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
18 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
19 | * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE |
20 | * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
21 | * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
22 | * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
23 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
24 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
25 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
26 | * POSSIBILITY OF SUCH DAMAGE. |
27 | */ |
28 | |
29 | /** |
30 | * \brief Ordered operators: provides all the other compare operators for types |
31 | * that provide equal and less-than. |
32 | * |
33 | * This is similar to Boost's totally_ordered class, but much simpler and |
34 | * without injecting the boost namespace into ADL lookup. |
35 | */ |
36 | |
37 | #ifndef UTIL_OPERATORS_H |
38 | #define UTIL_OPERATORS_H |
39 | |
40 | namespace ue2 { |
41 | |
42 | /** |
43 | * \brief Ordered operators: provides all the other compare operators for types |
44 | * that provide equal and less-than. |
45 | * |
46 | * Simply inherit from this class with your class name as its template |
47 | * parameter. |
48 | */ |
49 | template<typename T> |
50 | class totally_ordered { |
51 | public: |
52 | friend bool operator!=(const T &a, const T &b) { return !(a == b); } |
53 | friend bool operator<=(const T &a, const T &b) { return !(b < a); } |
54 | friend bool operator>(const T &a, const T &b) { return b < a; } |
55 | friend bool operator>=(const T &a, const T &b) { return !(a < b); } |
56 | }; |
57 | |
58 | } // namespace |
59 | |
60 | #endif // UTIL_OPERATORS_H |
61 | |