Chris@16
|
1 /*=============================================================================
|
Chris@16
|
2 Copyright (c) 2001-2011 Joel de Guzman
|
Chris@16
|
3
|
Chris@16
|
4 Distributed under the Boost Software License, Version 1.0. (See accompanying
|
Chris@16
|
5 file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
|
Chris@16
|
6 =============================================================================*/
|
Chris@16
|
7 #if !defined(SPIRIT_HOLD_FEBRUARY_6_2010_0917AM)
|
Chris@16
|
8 #define SPIRIT_HOLD_FEBRUARY_6_2010_0917AM
|
Chris@16
|
9
|
Chris@16
|
10 #if defined(_MSC_VER)
|
Chris@16
|
11 #pragma once
|
Chris@16
|
12 #endif
|
Chris@16
|
13
|
Chris@16
|
14 #include <boost/spirit/home/qi/meta_compiler.hpp>
|
Chris@16
|
15 #include <boost/spirit/home/qi/skip_over.hpp>
|
Chris@16
|
16 #include <boost/spirit/home/qi/parser.hpp>
|
Chris@16
|
17 #include <boost/spirit/home/support/attributes.hpp>
|
Chris@16
|
18 #include <boost/spirit/home/support/info.hpp>
|
Chris@16
|
19 #include <boost/spirit/home/support/common_terminals.hpp>
|
Chris@16
|
20 #include <boost/spirit/home/support/unused.hpp>
|
Chris@16
|
21 #include <boost/spirit/home/support/has_semantic_action.hpp>
|
Chris@16
|
22 #include <boost/spirit/home/support/handles_container.hpp>
|
Chris@16
|
23
|
Chris@16
|
24 namespace boost { namespace spirit
|
Chris@16
|
25 {
|
Chris@16
|
26 ///////////////////////////////////////////////////////////////////////////
|
Chris@16
|
27 // Enablers
|
Chris@16
|
28 ///////////////////////////////////////////////////////////////////////////
|
Chris@16
|
29 template <>
|
Chris@16
|
30 struct use_directive<qi::domain, tag::hold> // enables hold
|
Chris@16
|
31 : mpl::true_ {};
|
Chris@16
|
32 }}
|
Chris@16
|
33
|
Chris@16
|
34 namespace boost { namespace spirit { namespace qi
|
Chris@16
|
35 {
|
Chris@16
|
36 #ifndef BOOST_SPIRIT_NO_PREDEFINED_TERMINALS
|
Chris@16
|
37 using spirit::hold;
|
Chris@16
|
38 #endif
|
Chris@16
|
39 using spirit::hold_type;
|
Chris@16
|
40
|
Chris@16
|
41 template <typename Subject>
|
Chris@16
|
42 struct hold_directive : unary_parser<hold_directive<Subject> >
|
Chris@16
|
43 {
|
Chris@16
|
44 typedef Subject subject_type;
|
Chris@16
|
45 hold_directive(Subject const& subject_)
|
Chris@16
|
46 : subject(subject_) {}
|
Chris@16
|
47
|
Chris@16
|
48 template <typename Context, typename Iterator>
|
Chris@16
|
49 struct attribute
|
Chris@16
|
50 {
|
Chris@16
|
51 typedef typename
|
Chris@16
|
52 traits::attribute_of<subject_type, Context, Iterator>::type
|
Chris@16
|
53 type;
|
Chris@16
|
54 };
|
Chris@16
|
55
|
Chris@16
|
56 template <typename Iterator, typename Context
|
Chris@16
|
57 , typename Skipper, typename Attribute>
|
Chris@16
|
58 bool parse(Iterator& first, Iterator const& last
|
Chris@16
|
59 , Context& context, Skipper const& skipper, Attribute& attr_) const
|
Chris@16
|
60 {
|
Chris@16
|
61 Attribute copy(attr_);
|
Chris@16
|
62 if (subject.parse(first, last, context, skipper, copy))
|
Chris@16
|
63 {
|
Chris@16
|
64 traits::swap_impl(copy, attr_);
|
Chris@16
|
65 return true;
|
Chris@16
|
66 }
|
Chris@16
|
67 return false;
|
Chris@16
|
68 }
|
Chris@16
|
69
|
Chris@16
|
70 template <typename Context>
|
Chris@16
|
71 info what(Context& context) const
|
Chris@16
|
72 {
|
Chris@16
|
73 return info("hold", subject.what(context));
|
Chris@16
|
74
|
Chris@16
|
75 }
|
Chris@16
|
76
|
Chris@16
|
77 Subject subject;
|
Chris@16
|
78 };
|
Chris@16
|
79
|
Chris@16
|
80 ///////////////////////////////////////////////////////////////////////////
|
Chris@16
|
81 // Parser generators: make_xxx function (objects)
|
Chris@16
|
82 ///////////////////////////////////////////////////////////////////////////
|
Chris@16
|
83 template <typename Subject, typename Modifiers>
|
Chris@16
|
84 struct make_directive<tag::hold, Subject, Modifiers>
|
Chris@16
|
85 {
|
Chris@16
|
86 typedef hold_directive<Subject> result_type;
|
Chris@16
|
87 result_type operator()(unused_type, Subject const& subject, unused_type) const
|
Chris@16
|
88 {
|
Chris@16
|
89 return result_type(subject);
|
Chris@16
|
90 }
|
Chris@16
|
91 };
|
Chris@16
|
92 }}}
|
Chris@16
|
93
|
Chris@16
|
94 namespace boost { namespace spirit { namespace traits
|
Chris@16
|
95 {
|
Chris@16
|
96 ///////////////////////////////////////////////////////////////////////////
|
Chris@16
|
97 template <typename Subject>
|
Chris@16
|
98 struct has_semantic_action<qi::hold_directive<Subject> >
|
Chris@16
|
99 : unary_has_semantic_action<Subject> {};
|
Chris@16
|
100
|
Chris@16
|
101 ///////////////////////////////////////////////////////////////////////////
|
Chris@16
|
102 template <typename Subject, typename Attribute, typename Context
|
Chris@16
|
103 , typename Iterator>
|
Chris@16
|
104 struct handles_container<qi::hold_directive<Subject>, Attribute
|
Chris@16
|
105 , Context, Iterator>
|
Chris@16
|
106 : unary_handles_container<Subject, Attribute, Context, Iterator> {};
|
Chris@16
|
107 }}}
|
Chris@16
|
108
|
Chris@16
|
109 #endif
|