1/*=============================================================================
2 Copyright (c) 2001-2015 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/spirit/home/x3.hpp>
8#include <boost/fusion/include/vector.hpp>
9#include <boost/fusion/include/at.hpp>
10
11#include <string>
12#include <iostream>
13#include "test.hpp"
14
15using boost::spirit::x3::rule;
16
17rule<class direct_rule, int> direct_rule = "direct_rule";
18rule<class indirect_rule, int> indirect_rule = "indirect_rule";
19
20auto const direct_rule_def = boost::spirit::x3::int_;
21auto const indirect_rule_def = direct_rule;
22
23BOOST_SPIRIT_DEFINE(direct_rule, indirect_rule)
24
25int
26main()
27{
28 using namespace boost::spirit::x3::ascii;
29 using boost::spirit::x3::omit;
30 using boost::spirit::x3::unused_type;
31 using boost::spirit::x3::unused;
32 using boost::spirit::x3::int_;
33
34 using boost::fusion::vector;
35 using boost::fusion::at_c;
36
37 using spirit_test::test;
38 using spirit_test::test_attr;
39
40 BOOST_SPIRIT_ASSERT_CONSTEXPR_CTORS(omit['x']);
41
42 {
43 BOOST_TEST(test("a", omit['a']));
44 }
45
46 {
47 // omit[] means we don't receive the attribute
48 char attr;
49 BOOST_TEST((test_attr("abc", omit[char_] >> omit['b'] >> char_, attr)));
50 BOOST_TEST((attr == 'c'));
51 }
52
53 {
54 // If all elements except 1 is omitted, the attribute is
55 // a single-element sequence. For this case alone, we allow
56 // naked attributes (unwrapped in a fusion sequence).
57 char attr;
58 BOOST_TEST((test_attr("abc", omit[char_] >> 'b' >> char_, attr)));
59 BOOST_TEST((attr == 'c'));
60 }
61
62 {
63 // omit[] means we don't receive the attribute
64 vector<> attr;
65 BOOST_TEST((test_attr("abc", omit[char_] >> omit['b'] >> omit[char_], attr)));
66 }
67
68 {
69 // omit[] means we don't receive the attribute
70 // this test is merely a compile test, because using a unused as the
71 // explicit attribute doesn't make any sense
72 unused_type attr;
73 BOOST_TEST((test_attr("abc", omit[char_ >> 'b' >> char_], attr)));
74 }
75
76 {
77 // omit[] means we don't receive the attribute, if all elements of a
78 // sequence have unused attributes, the whole sequence has an unused
79 // attribute as well
80 vector<char, char> attr;
81 BOOST_TEST((test_attr("abcde",
82 char_ >> (omit[char_] >> omit['c'] >> omit[char_]) >> char_, attr)));
83 BOOST_TEST((at_c<0>(attr) == 'a'));
84 BOOST_TEST((at_c<1>(attr) == 'e'));
85 }
86
87 {
88 // "hello" has an unused_type. unused attrubutes are not part of the sequence
89 vector<char, char> attr;
90 BOOST_TEST((test_attr("a hello c", char_ >> "hello" >> char_, attr, space)));
91 BOOST_TEST((at_c<0>(attr) == 'a'));
92 BOOST_TEST((at_c<1>(attr) == 'c'));
93 }
94
95 {
96 // if only one node in a sequence is left (all the others are omitted),
97 // then we need "naked" attributes (not wrapped in a tuple)
98 int attr;
99 BOOST_TEST((test_attr("a 123 c", omit['a'] >> int_ >> omit['c'], attr, space)));
100 BOOST_TEST((attr == 123));
101 }
102
103 {
104 // unused means we don't care about the attribute
105 BOOST_TEST((test_attr("abc", char_ >> 'b' >> char_, unused)));
106 }
107
108 { // test action with omitted attribute
109 char c = 0;
110 auto f = [&](auto& ctx){ c = _attr(ctx); };
111
112 BOOST_TEST(test("x123\"a string\"", (char_ >> omit[int_] >> "\"a string\"")[f]));
113 BOOST_TEST(c == 'x');
114 }
115
116 { // test action with omitted attribute
117 int n = 0;
118 auto f = [&](auto& ctx){ n = _attr(ctx); };
119
120 BOOST_TEST(test("x 123 \"a string\"", (omit[char_] >> int_ >> "\"a string\"")[f], space));
121 BOOST_TEST(n == 123);
122 }
123
124 {
125 // test with simple rule
126 BOOST_TEST((test_attr("123", omit[direct_rule], unused)));
127 }
128
129 {
130 // test with complex rule
131 BOOST_TEST((test_attr("123", omit[indirect_rule], unused)));
132 }
133
134 return boost::report_errors();
135}
136

source code of boost/libs/spirit/test/x3/omit.cpp