mdds
ref_pair.hpp
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3 *
4 * Copyright (c) 2020 Kohei Yoshida
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28
29#ifndef INCLUDED_MDDS_REF_PAIR_HPP
30#define INCLUDED_MDDS_REF_PAIR_HPP
31
32#include <type_traits>
33
34namespace mdds { namespace detail {
35
36template<typename T1, typename T2>
38{
39 using first_type = typename std::add_lvalue_reference<T1>::type;
40 using second_type = typename std::add_lvalue_reference<T2>::type;
41
42 first_type first;
43 second_type second;
44
45 ref_pair(first_type _first, second_type _second) : first(_first), second(_second)
46 {}
47
48 ref_pair(const ref_pair& other) = default;
49
50 bool operator==(const std::pair<typename std::decay<T1>::type, typename std::decay<T2>::type>& other) const
51 {
52 return first == other.first && second == other.second;
53 }
54
55 bool operator!=(const std::pair<typename std::decay<T1>::type, typename std::decay<T2>::type>& other) const
56 {
57 return !operator==(other);
58 }
59
60 bool operator==(const ref_pair& other) const
61 {
62 return first == other.first && second == other.second;
63 }
64
65 bool operator!=(const ref_pair& other) const
66 {
67 return !operator==(other);
68 }
69
70 ref_pair* operator->()
71 {
72 return this;
73 }
74};
75
76}} // namespace mdds::detail
77
78#endif
79
80/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
Definition: ref_pair.hpp:38