1/*=============================================================================
2Copyright (c) 2016 Frank Hein, maxence business consulting gmbh
3
4Distributed under the Boost Software License, Version 1.0. (See accompanying
5file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
6==============================================================================*/
7#ifndef BOOST_SPIRIT_QI_DIRECTIVE_EXPECT_HPP
8#define BOOST_SPIRIT_QI_DIRECTIVE_EXPECT_HPP
9
10#if defined(_MSC_VER)
11#pragma once
12#endif
13
14#include <boost/spirit/home/qi/meta_compiler.hpp>
15#include <boost/spirit/home/support/has_semantic_action.hpp>
16#include <boost/spirit/home/qi/detail/attributes.hpp>
17#include <boost/spirit/home/qi/detail/expectation_failure.hpp>
18#include <boost/spirit/home/support/common_terminals.hpp>
19#include <boost/spirit/home/support/handles_container.hpp>
20#include <boost/spirit/home/support/unused.hpp>
21#include <boost/spirit/home/support/info.hpp>
22
23namespace boost { namespace spirit {
24 ///////////////////////////////////////////////////////////////////////////
25 // Enablers
26 ///////////////////////////////////////////////////////////////////////////
27 template <>
28 struct use_directive<qi::domain, tag::expect> // enables expect[p]
29 : mpl::true_ {};
30}}
31
32namespace boost { namespace spirit { namespace qi {
33
34#ifndef BOOST_SPIRIT_NO_PREDEFINED_TERMINALS
35 using spirit::expect;
36#endif
37 using spirit::expect_type;
38
39 template <typename Subject>
40 struct expect_directive : unary_parser<expect_directive<Subject> >
41 {
42 typedef result_of::compile<domain, Subject> subject_type;
43
44 template <typename Context, typename Iterator>
45 struct attribute
46 {
47 typedef traits::attribute_of<subject_type, Context, Iterator>
48 type;
49 };
50
51 expect_directive(Subject const& subject_) : subject(subject_) {}
52
53 template <typename Iterator, typename Context
54 , typename Skipper, typename Attribute>
55 bool parse(Iterator& first, Iterator const& last
56 , Context& context, Skipper const& skipper
57 , Attribute& attr_) const
58 {
59 typedef expectation_failure<Iterator> exception;
60
61 if (!subject.parse(first, last, context, skipper, attr_))
62 {
63 boost::throw_exception(
64 exception(first, last, subject.what(context)));
65#if defined(BOOST_NO_EXCEPTIONS)
66 return false; // for systems not supporting exceptions
67#endif
68 }
69 return true;
70 }
71
72 template <typename Context>
73 info what(Context& context) const
74 {
75 return info("expect", subject.what(context));
76 }
77
78 Subject subject;
79 };
80
81 ///////////////////////////////////////////////////////////////////////////
82 // Parser generators: make_xxx function (objects)
83 ///////////////////////////////////////////////////////////////////////////
84 template <typename Subject, typename Modifiers>
85 struct make_directive<tag::expect, Subject, Modifiers>
86 {
87 typedef expect_directive<Subject> result_type;
88
89 result_type operator()
90 (unused_type, Subject const& subject, unused_type) const
91 {
92 return result_type(subject);
93 }
94 };
95
96}}}
97
98namespace boost { namespace spirit { namespace traits {
99 ///////////////////////////////////////////////////////////////////////////
100 template <typename Subject>
101 struct has_semantic_action<qi::expect_directive<Subject> >
102 : unary_has_semantic_action<Subject> {};
103
104 ///////////////////////////////////////////////////////////////////////////
105 template <typename Subject, typename Attribute
106 , typename Context, typename Iterator>
107 struct handles_container<
108 qi::expect_directive<Subject>, Attribute, Context, Iterator
109 >
110 : unary_handles_container<Subject, Attribute, Context, Iterator> {};
111}}}
112
113#endif
114

source code of boost/libs/spirit/include/boost/spirit/home/qi/directive/expect.hpp