1/*=============================================================================
2 Copyright (c) 2001-2007 Joel de Guzman
3
4 Distributed under the Boost Software License, Version 1.0. (See accompanying
5 file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
6==============================================================================*/
7#include <iostream>
8#include <cmath>
9#include <algorithm>
10#include <vector>
11
12#include <boost/phoenix/core/limits.hpp>
13
14#include <boost/detail/lightweight_test.hpp>
15#include <boost/fusion/tuple.hpp>
16#include <boost/phoenix/core.hpp>
17#include <boost/phoenix/operator.hpp>
18#include <boost/phoenix/function.hpp>
19#include <boost/phoenix/fusion.hpp>
20#include <boost/phoenix/scope.hpp>
21
22#include <typeinfo>
23
24namespace fusion = boost::fusion;
25namespace mpl = boost::mpl;
26
27int
28main()
29{
30 using boost::phoenix::let;
31 using boost::phoenix::val;
32 using boost::phoenix::arg_names::_1;
33 using boost::phoenix::arg_names::_2;
34 //using boost::phoenix::arg_names::_3;
35 using boost::phoenix::local_names::_a;
36 using boost::phoenix::local_names::_b;
37 //using boost::phoenix::local_names::_c;
38 //using boost::phoenix::local_names::_d;
39 //using boost::phoenix::local_names::_e;
40 //using boost::phoenix::local_names::_x;
41 //using boost::phoenix::local_names::_y;
42 //using boost::phoenix::local_names::_z;
43 //using boost::phoenix::placeholders::arg1;
44 /*
45 {
46 int x = 1;
47 BOOST_TEST(
48 let(_a = _1)
49 [
50 _a
51 ]
52 (x) == x
53 )
54 ;
55 }
56
57 {
58 int x = 1, y = 10;
59 BOOST_TEST(
60 let(_a = _1, _b = _2)
61 [
62 _a + _b
63 ]
64 (x, y) == x + y
65 );
66 }
67
68 {
69 int x = 1, y = 10, z = 13;
70 BOOST_TEST(
71 let(_x = _1, _y = _2)
72 [
73 let(_z = _3)
74 [
75 _x + _y + _z
76 ]
77 ]
78 (x, y, z) == x + y + z
79 );
80 }
81
82 {
83 int x = 1, y = 10;
84 BOOST_TEST(
85 let(_x = _1)
86 [
87 _x +
88 let(_x = _2)
89 [
90 -_x
91 ]
92 ]
93 (x, y) == x + -y
94 );
95 }
96
97 {
98 int x = 999;
99 BOOST_TEST(
100 let(_x = _1) // _x is a reference to x
101 [
102 _x += 888
103 ]
104 (x) == 999 + 888
105 );
106
107 BOOST_TEST(x == 888 + 999);
108 }
109
110 {
111 int x = 999;
112
113 BOOST_TEST(
114 let(_x = val(_1)) // _x holds x by value
115 [
116 _x += 888
117 ]
118 (x) == x + 888
119 );
120
121 BOOST_TEST(x == 999);
122
123 BOOST_TEST(
124 let(_x = val(_1)) // _x holds x by value
125 [
126 val(_x += 888)
127 ]
128 (x) == x + 888
129 );
130
131 BOOST_TEST(x == 999);
132 }
133
134 {
135 BOOST_TEST(
136 let(_a = 1, _b = 2, _c = 3, _d = 4, _e = 5)
137 [
138 _a + _b + _c + _d + _e
139 ]
140 () == 1 + 2 + 3 + 4 + 5
141 );
142 }
143
144#ifdef PHOENIX_SHOULD_NOT_COMPILE_TEST
145 {
146 // disallow this:
147 int i;
148 (_a + _b)(i);
149 }
150#endif
151 */
152 {
153 // show that we can return a local from an outer scope
154 int y = 0;
155 int x = (let(a: _a = _2)[let(a: _b = _1)[ _a ]])(y,1);
156
157 BOOST_TEST(x == 1);
158 }
159 /*
160 {
161 // show that this code returns an lvalue
162 int i = 1;
163 let(_a = arg1)[ _a ](i)++;
164 BOOST_TEST(i == 2);
165 }
166
167 {
168 // show that what you put in is what you get out
169 int i = 1;
170 int& j = let(_a = arg1)[_a](i);
171 BOOST_TEST(&i == &j);
172 }
173
174 {
175 using boost::phoenix::at_c;
176
177 boost::fusion::tuple<int, int> t = boost::fusion::make_tuple(0, 1);
178 int i = let(_a = at_c<0>(_1))[_a](t);
179
180 BOOST_TEST( i == 0 );
181 }
182
183 {
184 int i = 0;
185 let(_a = _1)[_a = _2](i, 2);
186 BOOST_TEST(i == 2);
187 }
188 */
189 return boost::report_errors();
190}
191
192

source code of boost/libs/phoenix/test/scope/let_tests_157a.cpp