1 /*=============================================================================
2 Copyright (c) 2011 Thomas Heller
3 Distributed under the Boost Software License, Version 1.0. (See accompanying
4 file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
5 ==============================================================================*/
6
7 #include <boost/phoenix/core.hpp>
8 #include <boost/phoenix/statement.hpp>
9 #include <boost/phoenix/operator.hpp>
10 #include <boost/phoenix/scope.hpp>
11 #include <iostream>
12 #include <boost/phoenix/scope/this.hpp>
13
14
15 template <typename T0>
f(T0 t)16 void f(T0 t)
17 {
18 std::cout << t(1) << "\n";
19 std::cout << t(2) << "\n";
20 std::cout << t(3) << "\n";
21 std::cout << t(4) << "\n";
22 std::cout << t(5) << "\n";
23 std::cout << t(6) << "\n";
24 std::cout << t(7) << "\n";
25 }
26
27 template <typename T0>
f_2(T0 t)28 void f_2(T0 t)
29 {
30 for(int i = 0; i < 10; ++i)
31 {
32 for(int j = 0; j < i; ++j)
33 {
34 std::cout << t(i, j) << " ";
35 }
36 std::cout << "\n";
37 }
38 }
39
main()40 int main()
41 {
42 //using boost::phoenix::_this;
43 using boost::phoenix::if_;
44 using boost::phoenix::if_else;
45 using boost::phoenix::val;
46 using boost::phoenix::let;
47 using boost::phoenix::nothing;
48 using boost::phoenix::arg_names::_1;
49 using boost::phoenix::arg_names::_2;
50 using boost::phoenix::local_names::_a;
51
52 f((
53 if_(_1 == 0)
54 [
55 std::cout << val("\n")
56 ]
57 .else_
58 [
59 std::cout << _1 << " "
60 , this_(_1 - 1)
61 ]
62 , val(0)
63 ));
64
65 /*
66 f((
67 if_else(
68 _1 == 0
69 , _1
70 ,this_(_1 - 1)
71 )
72 ));
73 */
74
75 f((
76 if_else(
77 _1 != 0
78 ,this_(_1 - 1)
79 , _1
80 )
81 ));
82 /*
83
84 f(( // fac(n) = n * fac(n-1); fac(1) = 1
85 if_else(
86 _1 <= 1
87 , 1
88 , _1 * _this(_1 - 1)
89 )
90 ));
91
92 f(( // fac(n) = n * fac(n-1); fac(1) = 1
93 if_else(
94 _1 > 1
95 , let(_a = _this(_1-1))[_1 * _a]
96 , 1
97 )
98 ));
99
100 f(( // fib(n) = fib(n-1) + fib(n-2); fib(0) = 0; fib(1) = 1
101 if_else(
102 _1 == 0
103 , 0
104 , if_else(
105 _1 == 1
106 , 1
107 , _this(_1 - 1) + _this(_1 - 2)
108 )
109 )
110 ));
111
112 f_2(( // bin(n, k) = bin(n-1, k-1) + bin(n-1, k); bin(n, 0) = 1; bin(0, k) = 0
113 if_else(
114 _1 == 0
115 , 0
116 , if_else(
117 _2 == 0
118 , 1
119 , _this(_1 - 1, _2 - 1) + _this(_1 - 1, _2)
120 )
121 )
122 ));
123 */
124 }
125