1///////////////////////////////////////////////////////////////////////////////
2// noinvoke.hpp
3//
4// Copyright 2008 Eric Niebler. Distributed under the Boost
5// Software License, Version 1.0. (See accompanying file
6// LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
7
8#include <boost/proto/core.hpp>
9#include <boost/proto/transform/make.hpp>
10#include <boost/type_traits/add_pointer.hpp>
11#include <boost/type_traits/remove_pointer.hpp>
12#include <boost/test/unit_test.hpp>
13namespace proto=boost::proto;
14using proto::_;
15
16struct Test
17 : proto::when<
18 _
19 , proto::noinvoke<
20 // This remove_pointer invocation is bloked by noinvoke
21 boost::remove_pointer<
22 // This add_pointer invocation is *not* blocked by noinvoke
23 boost::add_pointer<_>
24 >
25 >()
26 >
27{};
28
29struct Test2
30 : proto::when<
31 _
32 // This add_pointer gets invoked because a substitution takes place
33 // within it.
34 , boost::add_pointer<
35 proto::noinvoke<
36 // This remove_pointer invocation is bloked by noinvoke
37 boost::remove_pointer<
38 // This add_pointer invocation is *not* blocked by noinvoke
39 boost::add_pointer<_>
40 >
41 >
42 >()
43 >
44{};
45
46template<typename T, typename U>
47struct select2nd
48{
49 typedef U type;
50};
51
52struct Test3
53 : proto::when<
54 _
55 // This add_pointer gets invoked because a substitution takes place
56 // within it.
57 , select2nd<
58 void
59 , proto::noinvoke<
60 // This remove_pointer invocation is bloked by noinvoke
61 select2nd<
62 void
63 // This add_pointer invocation is *not* blocked by noinvoke
64 , boost::add_pointer<_>
65 >
66 >
67 >()
68 >
69{};
70
71
72void test_noinvoke()
73{
74 typedef proto::terminal<int>::type Int;
75 Int i = {.child0: 42};
76
77 BOOST_MPL_ASSERT((
78 boost::is_same<
79 boost::result_of<Test(Int)>::type
80 , boost::remove_pointer<Int *>
81 >
82 ));
83
84 boost::remove_pointer<Int *> t = Test()(i);
85
86 BOOST_MPL_ASSERT((
87 boost::is_same<
88 boost::result_of<Test2(Int)>::type
89 , boost::remove_pointer<Int *> *
90 >
91 ));
92
93 boost::remove_pointer<Int *> * t2 = Test2()(i);
94
95 BOOST_MPL_ASSERT((
96 boost::is_same<
97 boost::result_of<Test3(Int)>::type
98 , select2nd<void, Int *>
99 >
100 ));
101
102 select2nd<void, Int *> t3 = Test3()(i);
103}
104
105using namespace boost::unit_test;
106///////////////////////////////////////////////////////////////////////////////
107// init_unit_test_suite
108//
109test_suite* init_unit_test_suite( int argc, char* argv[] )
110{
111 test_suite *test = BOOST_TEST_SUITE("test proto::noinvoke");
112
113 test->add(BOOST_TEST_CASE(&test_noinvoke));
114
115 return test;
116}
117

source code of boost/libs/proto/test/noinvoke.cpp