1/*=============================================================================
2 Copyright (c) 2001-2011 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#if !defined(BOOST_SPIRIT_META_COMPILER_OCTOBER_16_2008_0347PM)
8#define BOOST_SPIRIT_META_COMPILER_OCTOBER_16_2008_0347PM
9
10#if defined(_MSC_VER)
11#pragma once
12#endif
13
14#include <boost/spirit/home/support/meta_compiler.hpp>
15#include <boost/spirit/home/qi/domain.hpp>
16#include <boost/spirit/home/qi/parser.hpp>
17#include <boost/spirit/home/support/string_traits.hpp>
18#include <boost/proto/tags.hpp>
19#include <boost/type_traits/remove_reference.hpp>
20#include <boost/utility/enable_if.hpp>
21#include <boost/fusion/include/at.hpp>
22
23namespace boost { namespace spirit
24{
25 template <typename T>
26 struct use_terminal<qi::domain, T
27 , typename enable_if<traits::is_parser<T> >::type> // enables parsers
28 : mpl::true_ {};
29
30 namespace qi
31 {
32 template <typename T, typename Modifiers, typename Enable = void>
33 struct make_primitive // by default, return it as-is
34 {
35 typedef T result_type;
36
37 template <typename T_>
38 T_& operator()(T_& val, unused_type) const
39 {
40 return val;
41 }
42
43 template <typename T_>
44 T_ const& operator()(T_ const& val, unused_type) const
45 {
46 return val;
47 }
48 };
49
50 template <typename Tag, typename Elements
51 , typename Modifiers, typename Enable = void>
52 struct make_composite;
53
54 template <typename Directive, typename Body
55 , typename Modifiers, typename Enable = void>
56 struct make_directive
57 {
58 typedef Body result_type;
59 result_type operator()(unused_type, Body const& body, unused_type) const
60 {
61 return body; // By default, a directive simply returns its subject
62 }
63 };
64 }
65
66 // Qi primitive meta-compiler
67 template <>
68 struct make_component<qi::domain, proto::tag::terminal>
69 {
70 template <typename Sig>
71 struct result;
72
73 template <typename This, typename Elements, typename Modifiers>
74 struct result<This(Elements, Modifiers)>
75 {
76 typedef typename qi::make_primitive<
77 typename remove_const<typename Elements::car_type>::type,
78 typename remove_reference<Modifiers>::type>::result_type
79 type;
80 };
81
82 template <typename Elements, typename Modifiers>
83 typename result<make_component(Elements, Modifiers)>::type
84 operator()(Elements const& elements, Modifiers const& modifiers) const
85 {
86 typedef typename remove_const<typename Elements::car_type>::type term;
87 return qi::make_primitive<term, Modifiers>()(elements.car, modifiers);
88 }
89 };
90
91 // Qi composite meta-compiler
92 template <typename Tag>
93 struct make_component<qi::domain, Tag>
94 {
95 template <typename Sig>
96 struct result;
97
98 template <typename This, typename Elements, typename Modifiers>
99 struct result<This(Elements, Modifiers)>
100 {
101 typedef typename
102 qi::make_composite<Tag, Elements,
103 typename remove_reference<Modifiers>::type>::result_type
104 type;
105 };
106
107 template <typename Elements, typename Modifiers>
108 typename result<make_component(Elements, Modifiers)>::type
109 operator()(Elements const& elements, Modifiers const& modifiers) const
110 {
111 return qi::make_composite<Tag, Elements, Modifiers>()(
112 elements, modifiers);
113 }
114 };
115
116 // Qi function meta-compiler
117 template <>
118 struct make_component<qi::domain, proto::tag::function>
119 {
120 template <typename Sig>
121 struct result;
122
123 template <typename This, typename Elements, typename Modifiers>
124 struct result<This(Elements, Modifiers)>
125 {
126 typedef typename
127 qi::make_composite<
128 typename remove_const<typename Elements::car_type>::type,
129 typename Elements::cdr_type,
130 typename remove_reference<Modifiers>::type
131 >::result_type
132 type;
133 };
134
135 template <typename Elements, typename Modifiers>
136 typename result<make_component(Elements, Modifiers)>::type
137 operator()(Elements const& elements, Modifiers const& modifiers) const
138 {
139 return qi::make_composite<
140 typename remove_const<typename Elements::car_type>::type,
141 typename Elements::cdr_type,
142 Modifiers>()(elements.cdr, modifiers);
143 }
144 };
145
146 // Qi directive meta-compiler
147 template <>
148 struct make_component<qi::domain, tag::directive>
149 {
150 template <typename Sig>
151 struct result;
152
153 template <typename This, typename Elements, typename Modifiers>
154 struct result<This(Elements, Modifiers)>
155 {
156 typedef typename
157 qi::make_directive<
158 typename remove_const<typename Elements::car_type>::type,
159 typename remove_const<typename Elements::cdr_type::car_type>::type,
160 typename remove_reference<Modifiers>::type
161 >::result_type
162 type;
163 };
164
165 template <typename Elements, typename Modifiers>
166 typename result<make_component(Elements, Modifiers)>::type
167 operator()(Elements const& elements, Modifiers const& modifiers) const
168 {
169 return qi::make_directive<
170 typename remove_const<typename Elements::car_type>::type,
171 typename remove_const<typename Elements::cdr_type::car_type>::type,
172 Modifiers>()(elements.car, elements.cdr.car, modifiers);
173 }
174 };
175
176}}
177
178#endif
179