1 /*=============================================================================
2 Copyright (c) 2015 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 <boost/detail/lightweight_test.hpp>
8 #include <boost/spirit/home/x3.hpp>
9 #include "test.hpp"
10
11 namespace x3 = boost::spirit::x3;
12
13 struct my_tag;
14
15 struct my_rule_class
16 {
17 template <typename Iterator, typename Exception, typename Context>
18 x3::error_handler_result
on_errormy_rule_class19 on_error(Iterator&, Iterator const&, Exception const&, Context const& context)
20 {
21 x3::get<my_tag>(context)++;
22 return x3::error_handler_result::fail;
23 }
24
25 template <typename Iterator, typename Attribute, typename Context>
26 inline void
on_successmy_rule_class27 on_success(Iterator const&, Iterator const&, Attribute&, Context const& context)
28 {
29 x3::get<my_tag>(context)++;
30 }
31 };
32
33 int
main()34 main()
35 {
36 using spirit_test::test_attr;
37 using spirit_test::test;
38
39 using boost::spirit::x3::rule;
40 using boost::spirit::x3::int_;
41 using boost::spirit::x3::with;
42
43 // read from a mutable field is not allowed on these compilers
44 #if (!defined(_MSC_VER) || _MSC_VER >= 1910) && \
45 (!defined(__clang__) || __clang_major__ >= 7)
46 BOOST_SPIRIT_ASSERT_CONSTEXPR_CTORS(with<my_tag>(0)['x']);
47 #endif
48 {
49 constexpr int i = 0;
50 BOOST_SPIRIT_ASSERT_CONSTEXPR_CTORS(with<my_tag>(i)['x']);
51 }
52
53 { // injecting data into the context in the grammar
54
55 int val = 0;
56 auto r = rule<my_rule_class, char const*>() =
57 '(' > int_ > ',' > int_ > ')'
58 ;
59
60 auto start =
61 with<my_tag>(std::ref(val)) [ r ]
62 ;
63
64 BOOST_TEST(test("(123,456)", start));
65 BOOST_TEST(!test("(abc,def)", start));
66 BOOST_TEST(val == 2);
67 }
68
69 { // injecting non-const lvalue into the context
70 int val = 0;
71 auto const r = int_[([](auto& ctx){
72 x3::get<my_tag>(ctx) += x3::_attr(ctx);
73 })];
74 BOOST_TEST(test("123,456", with<my_tag>(val)[r % ',']));
75 BOOST_TEST(579 == val);
76 }
77
78 { // injecting rvalue into the context
79 auto const r1 = int_[([](auto& ctx){
80 x3::get<my_tag>(ctx) += x3::_attr(ctx);
81 })];
82 auto const r2 = rule<struct my_rvalue_rule_class, int>() =
83 x3::lit('(') >> (r1 % ',') >> x3::lit(')')[([](auto& ctx){
84 x3::_val(ctx) = x3::get<my_tag>(ctx);
85 })];
86 int attr = 0;
87 BOOST_TEST(test_attr("(1,2,3)", with<my_tag>(100)[r2], attr));
88 BOOST_TEST(106 == attr);
89 }
90
91 { // injecting const/non-const lvalue and rvalue into the context
92 struct functor {
93 int operator()(int& val) {
94 return val * 10; // non-const ref returns 10 * injected val
95 }
96 int operator()(int const& val) {
97 return val; // const ref returns injected val
98 }
99 };
100
101 auto f = [](auto& ctx){
102 x3::_val(ctx) = x3::_attr(ctx) + functor()(x3::get<my_tag>(ctx));
103 };
104 auto const r = rule<struct my_rule_class2, int>() = int_[f];
105
106 int attr = 0;
107 int const cval = 10;
108 BOOST_TEST(test_attr("5", with<my_tag>(cval)[r], attr));
109 BOOST_TEST(15 == attr); // x3::get returns const ref to cval
110
111 attr = 0;
112 int val = 10;
113 BOOST_TEST(test_attr("5", with<my_tag>(val)[r], attr));
114 BOOST_TEST(105 == attr); // x3::get returns ref to val
115
116 attr = 0;
117
118 BOOST_TEST(test_attr("5", with<my_tag>(10)[r], attr));
119 // x3::get returns ref to member variable of with_directive
120 BOOST_TEST(105 == attr);
121 }
122
123 return boost::report_errors();
124 }
125