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
|
/*=============================================================================
Copyright (c) 2001-2007 Joel de Guzman
Copyright (c) 2015 John Fletcher
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 <iostream>
#include <cmath>
#include <boost/detail/lightweight_test.hpp>
#include <boost/phoenix/core.hpp>
#include <boost/phoenix/operator.hpp>
#include <boost/phoenix/bind.hpp>
namespace phoenix = boost::phoenix;
using std::cout;
using std::pow;
struct test
{
typedef void result_type;
void
operator()() const
{
cout << "Test lazy functions...\n";
}
};
struct sqr
{
template <typename Sig>
struct result;
template <typename This, typename Arg>
struct result<This(Arg&)>
{
typedef Arg type;
};
template <typename Arg>
Arg
operator()(Arg n) const
{
return n * n;
}
};
struct fact
{
template <typename Sig>
struct result;
template <typename This, typename Arg>
struct result<This(Arg&)>
{
typedef Arg type;
};
template <typename Arg>
Arg
operator()(Arg n) const
{
return (n <= 0) ? 1 : n * (*this)(n-1);
}
};
struct power
{
template<typename Sig>
struct result;
template<typename This, typename Arg1, typename Arg2>
struct result<This(Arg1&, Arg2&)>
{
typedef Arg1 type;
};
template <typename Arg1, typename Arg2>
Arg1
operator()(Arg1 a, Arg2 b) const
{
return pow(a, b);
}
};
struct add
{
template <typename Sig>
struct result;
template <typename This, typename Arg1, typename Arg2, typename Arg3, typename Arg4>
struct result<This(Arg1&, Arg2&, Arg3&, Arg4&)>
{
typedef Arg1 type;
};
template <typename Arg1, typename Arg2, typename Arg3, typename Arg4>
Arg1
operator()(Arg1 a, Arg2 b, Arg3 c, Arg4 d) const
{
return a + b + c + d;
}
};
int
main()
{
using phoenix::bind;
using phoenix::ref;
using phoenix::arg_names::_1;
using phoenix::arg_names::arg1;
using phoenix::arg_names::arg2;
int i5 = 5;
double d5 = 5, d3 = 3;
test()();
BOOST_TEST(bind(sqr(), arg1)(i5) == (i5*i5));
BOOST_TEST(bind(fact(), 4)() == 24);
BOOST_TEST(bind(fact(), arg1)(i5) == 120);
BOOST_TEST((int)bind(power(), arg1, arg2)(d5, d3) == (int)std::pow(d5, d3));
BOOST_TEST((bind(sqr(), arg1) + 5)(i5) == ((i5*i5)+5));
BOOST_TEST(bind(add(), arg1, arg1, arg1, arg1)(i5) == (5+5+5+5));
int const ic5 = 5;
// testing consts
BOOST_TEST(bind(sqr(), arg1)(ic5) == (ic5*ic5));
// From Steven Watanabe
sqr s;
int x = 2;
int result = bind(ref(s), _1)(x);
BOOST_TEST(result == 4);
return boost::report_errors();
}
|