1 // Copyright (C) 2016-2018 T. Zachary Laine
2 //
3 // Distributed under the Boost Software License, Version 1.0. (See
4 // accompanying file LICENSE_1_0.txt or copy at
5 // http://www.boost.org/LICENSE_1_0.txt)
6 #include <boost/yap/expression.hpp>
7
8 #include <boost/assign/list_of.hpp>
9
10 #include <map>
11 #include <iostream>
12
13
14 template<typename Key, typename Value, typename Allocator>
15 struct map_list_of_transform
16 {
17 template<typename Fn, typename Key2, typename Value2>
operator ()map_list_of_transform18 auto operator()(
19 boost::yap::expr_tag<boost::yap::expr_kind::call>,
20 Fn const & fn,
21 Key2 && key,
22 Value2 && value)
23 {
24 boost::yap::transform(
25 boost::yap::as_expr<boost::yap::minimal_expr>(fn), *this);
26 map.emplace(
27 Key{std::forward<Key2 &&>(key)},
28 Value{std::forward<Value2 &&>(value)});
29 return 0;
30 }
31
32 std::map<Key, Value, Allocator> map;
33 };
34
35
36 template<boost::yap::expr_kind Kind, typename Tuple>
37 struct map_list_of_expr
38 {
39 static boost::yap::expr_kind const kind = Kind;
40
41 Tuple elements;
42
43 template<typename Key, typename Value, typename Allocator>
operator std::map<Key,Value,Allocator>map_list_of_expr44 operator std::map<Key, Value, Allocator>() const
45 {
46 map_list_of_transform<Key, Value, Allocator> transform;
47 boost::yap::transform(*this, transform);
48 return transform.map;
49 }
50
51 BOOST_YAP_USER_CALL_OPERATOR(::map_list_of_expr)
52 };
53
54 struct map_list_of_tag
55 {};
56
57 auto map_list_of =
58 boost::yap::make_terminal<map_list_of_expr>(map_list_of_tag{});
59
60
61 #if __GNUC__ || __clang__
62 #define NOINLINE __attribute__((noinline))
63 #else
64 #define NOINLINE
65 #endif
66
67
make_map_with_boost_yap()68 NOINLINE std::map<std::string, int> make_map_with_boost_yap()
69 {
70 return map_list_of("<", 1)("<=", 2)(">", 3)(">=", 4)("=", 5)("<>", 6);
71 }
72
73
make_map_with_boost_assign()74 NOINLINE std::map<std::string, int> make_map_with_boost_assign()
75 {
76 return boost::assign::map_list_of("<", 1)("<=", 2)(">", 3)(">=", 4)("=", 5)(
77 "<>", 6);
78 }
79
80
make_map_manually()81 NOINLINE std::map<std::string, int> make_map_manually()
82 {
83 std::map<std::string, int> retval;
84 retval.emplace("<", 1);
85 retval.emplace("<=", 2);
86 retval.emplace(">", 3);
87 retval.emplace(">=", 4);
88 retval.emplace("=", 5);
89 retval.emplace("<>", 6);
90 return retval;
91 }
92
93
make_map_inializer_list()94 NOINLINE std::map<std::string, int> make_map_inializer_list()
95 {
96 std::map<std::string, int> retval = {
97 {"<", 1}, {"<=", 2}, {">", 3}, {">=", 4}, {"=", 5}, {"<>", 6}};
98 return retval;
99 }
100
101
main()102 int main()
103 {
104 {
105 std::map<std::string, int> op = make_map_with_boost_yap();
106
107 std::cout << "\"<\" --> " << op["<"] << std::endl;
108 std::cout << "\"<=\" --> " << op["<="] << std::endl;
109 std::cout << "\">\" --> " << op[">"] << std::endl;
110 std::cout << "\">=\" --> " << op[">="] << std::endl;
111 std::cout << "\"=\" --> " << op["="] << std::endl;
112 std::cout << "\"<>\" --> " << op["<>"] << std::endl;
113 }
114
115 {
116 std::map<std::string, int> op = make_map_with_boost_assign();
117
118 std::cout << "\"<\" --> " << op["<"] << std::endl;
119 std::cout << "\"<=\" --> " << op["<="] << std::endl;
120 std::cout << "\">\" --> " << op[">"] << std::endl;
121 std::cout << "\">=\" --> " << op[">="] << std::endl;
122 std::cout << "\"=\" --> " << op["="] << std::endl;
123 std::cout << "\"<>\" --> " << op["<>"] << std::endl;
124 }
125
126 {
127 std::map<std::string, int> op = make_map_manually();
128
129 std::cout << "\"<\" --> " << op["<"] << std::endl;
130 std::cout << "\"<=\" --> " << op["<="] << std::endl;
131 std::cout << "\">\" --> " << op[">"] << std::endl;
132 std::cout << "\">=\" --> " << op[">="] << std::endl;
133 std::cout << "\"=\" --> " << op["="] << std::endl;
134 std::cout << "\"<>\" --> " << op["<>"] << std::endl;
135 }
136
137 {
138 std::map<std::string, int> op = make_map_inializer_list();
139
140 std::cout << "\"<\" --> " << op["<"] << std::endl;
141 std::cout << "\"<=\" --> " << op["<="] << std::endl;
142 std::cout << "\">\" --> " << op[">"] << std::endl;
143 std::cout << "\">=\" --> " << op[">="] << std::endl;
144 std::cout << "\"=\" --> " << op["="] << std::endl;
145 std::cout << "\"<>\" --> " << op["<>"] << std::endl;
146 }
147
148 return 0;
149 }
150