1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
|
/*=============================================================================
Copyright (c) 2001-2011 Joel de Guzman
Copyright (c) 2007 Dan Marsden
Distributed under the Boost Software License, Version 1.0. (See accompanying
file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
==============================================================================*/
#include <boost/detail/lightweight_test.hpp>
#include <boost/fusion/container/vector/vector.hpp>
#include <boost/fusion/adapted/mpl.hpp>
#include <boost/fusion/sequence/io/out.hpp>
#include <boost/fusion/sequence/intrinsic/at.hpp>
#include <boost/fusion/container/generation/make_vector.hpp>
#include <boost/fusion/algorithm/iteration/fold.hpp>
#include <boost/fusion/algorithm/iteration/accumulate.hpp>
#include <boost/type_traits/is_same.hpp>
#include <boost/mpl/if.hpp>
#include <boost/mpl/next.hpp>
#include <boost/mpl/int.hpp>
#include <boost/mpl/vector.hpp>
#include <boost/type_traits/remove_const.hpp>
#include <boost/type_traits/remove_reference.hpp>
#include <boost/type_traits/is_reference.hpp>
#include <string>
using boost::mpl::if_;
using boost::mpl::int_;
using boost::is_same;
struct add_ints_only
{
template<typename T>
struct result;
template <typename State, typename T>
struct result<add_ints_only(State, T)>
{
typedef typename boost::remove_const<
typename boost::remove_reference<State>::type>::type type;
};
template <typename State, typename T>
State
operator()(State const& state, T const& /*x*/) const
{
return state;
}
int
operator()(int state, int x) const
{
return x + state;
}
};
struct count_ints
{
template<typename T>
struct result;
template <typename CountT, typename T>
struct result<count_ints(CountT, T)>
{
typedef typename boost::remove_const<
typename boost::remove_reference<CountT>::type>::type state;
typedef typename boost::remove_const<
typename boost::remove_reference<T>::type>::type elem;
typedef typename
if_<
is_same<elem, int>
, typename boost::mpl::next<state>::type
, state
>::type
type;
};
template <typename CountT, typename T>
typename result<count_ints(CountT, T)>::type
operator()(CountT const&, T const&) const
{
typedef typename result<count_ints(CountT, T)>::type result_;
return result_();
}
};
struct appender
{
typedef std::string result_type;
std::string operator()(std::string const& str, char c) const
{
return str + c;
}
};
struct lvalue_adder
{
template<typename Sig>
struct result;
template<typename T0, typename T1>
struct result<lvalue_adder(T0, T1&)>
{
// Second argument still needs to support rvalues - see definition of fusion::fold
typedef T1 type;
};
template<typename T0, typename T1>
T1 operator()(T0 const& lhs, T1& rhs) const
{
return lhs + rhs;
}
};
int add(int lhs, int rhs)
{
return lhs + rhs;
}
int
main()
{
using namespace boost::fusion;
namespace fusion = boost::fusion;
{
typedef vector<int, char, int, double> vector_type;
vector_type v(12345, 'x', 678910, 3.36);
int result = fold(v, 0, add_ints_only());
std::cout << result << std::endl;
BOOST_TEST(result == 12345+678910);
}
{
typedef vector<int> vector_type;
vector_type v(12345);
int n = fusion::fold(v, int_<0>(), count_ints());
std::cout << n << std::endl;
BOOST_TEST(n == 1);
}
{
typedef vector<int, char, int, double, int> vector_type;
vector_type v(12345, 'x', 678910, 3.36, 8756);
int n = fusion::fold(v, int_<0>(), count_ints());
std::cout << n << std::endl;
BOOST_TEST(n == 3);
}
{
typedef boost::mpl::vector<int, char, int, double, int> mpl_vec;
int n = fusion::fold(mpl_vec(), int_<0>(), count_ints());
std::cout << n << std::endl;
BOOST_TEST(n == 3);
}
{
BOOST_TEST(fusion::fold(fusion::make_vector('a','b','c','d','e'), std::string(""), appender())
== "abcde");
}
{
vector<int, int> vec(1,2);
BOOST_TEST(fusion::fold(vec, 0, lvalue_adder()) == 3);
}
{
vector<int, int> vec(1,2);
BOOST_TEST(fusion::fold(vec, 0, add) == 3);
}
{
typedef vector<int, char, int, double> vector_type;
vector_type v(12345, 'x', 678910, 3.36);
int result = accumulate(v, 0, add_ints_only());
std::cout << result << std::endl;
BOOST_TEST(result == 12345+678910);
}
{
typedef vector<int> vector_type;
vector_type v(12345);
int n = fusion::accumulate(v, int_<0>(), count_ints());
std::cout << n << std::endl;
BOOST_TEST(n == 1);
}
{
typedef vector<int, char, int, double, int> vector_type;
vector_type v(12345, 'x', 678910, 3.36, 8756);
int n = fusion::accumulate(v, int_<0>(), count_ints());
std::cout << n << std::endl;
BOOST_TEST(n == 3);
}
{
typedef boost::mpl::vector<int, char, int, double, int> mpl_vec;
int n = fusion::accumulate(mpl_vec(), int_<0>(), count_ints());
std::cout << n << std::endl;
BOOST_TEST(n == 3);
}
{
BOOST_TEST(fusion::accumulate(fusion::make_vector('a','b','c','d','e'), std::string(""), appender())
== "abcde");
}
{
vector<int, int> vec(1,2);
BOOST_TEST(fusion::accumulate(vec, 0, add) == 3);
}
return boost::report_errors();
}
|
