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_INFO_NOVEMBER_22_2008_1132AM)
8#define BOOST_SPIRIT_INFO_NOVEMBER_22_2008_1132AM
9
10#if defined(_MSC_VER)
11#pragma once
12#endif
13
14#include <boost/variant/variant.hpp>
15#include <boost/variant/recursive_variant.hpp>
16#include <boost/variant/apply_visitor.hpp>
17#include <boost/spirit/home/support/utf8.hpp>
18#include <list>
19#include <iterator>
20#include <utility>
21
22namespace boost { namespace spirit
23{
24 // info provides information about a component. Each component
25 // has a what member function that returns an info object.
26 // strings in the info object are assumed to be encoded as UTF8
27 // for uniformity.
28 struct info
29 {
30 struct nil_ {};
31
32 typedef
33 boost::variant<
34 nil_
35 , utf8_string
36 , recursive_wrapper<info>
37 , recursive_wrapper<std::pair<info, info> >
38 , recursive_wrapper<std::list<info> >
39 >
40 value_type;
41
42 explicit info(utf8_string const& tag_)
43 : tag(tag_), value(nil_()) {}
44
45 template <typename T>
46 info(utf8_string const& tag_, T const& value_)
47 : tag(tag_), value(value_) {}
48
49 info(utf8_string const& tag_, char value_)
50 : tag(tag_), value(utf8_string(1, value_)) {}
51
52 info(utf8_string const& tag_, wchar_t value_)
53 : tag(tag_), value(to_utf8(value: value_)) {}
54
55 info(utf8_string const& tag_, ucs4_char value_)
56 : tag(tag_), value(to_utf8(value: value_)) {}
57
58 template <typename Char>
59 info(utf8_string const& tag_, Char const* str)
60 : tag(tag_), value(to_utf8(str)) {}
61
62 template <typename Char, typename Traits, typename Allocator>
63 info(utf8_string const& tag_
64 , std::basic_string<Char, Traits, Allocator> const& str)
65 : tag(tag_), value(to_utf8(str)) {}
66
67 utf8_string tag;
68 value_type value;
69 };
70
71#ifdef _MSC_VER
72# pragma warning(push)
73# pragma warning(disable: 4512) // assignment operator could not be generated.
74#endif
75 template <typename Callback>
76 struct basic_info_walker
77 {
78 typedef void result_type;
79 typedef basic_info_walker<Callback> this_type;
80
81 basic_info_walker(Callback& callback_, utf8_string const& tag_, int depth_)
82 : callback(callback_), tag(tag_), depth(depth_) {}
83
84 void operator()(info::nil_) const
85 {
86 callback.element(tag, "", depth);
87 }
88
89 void operator()(utf8_string const& str) const
90 {
91 callback.element(tag, str, depth);
92 }
93
94 void operator()(info const& what) const
95 {
96 boost::apply_visitor(
97 this_type(callback, what.tag, depth+1), what.value);
98 }
99
100 void operator()(std::pair<info, info> const& pair) const
101 {
102 callback.element(tag, "", depth);
103 boost::apply_visitor(
104 this_type(callback, pair.first.tag, depth+1), pair.first.value);
105 boost::apply_visitor(
106 this_type(callback, pair.second.tag, depth+1), pair.second.value);
107 }
108
109 void operator()(std::list<info> const& l) const
110 {
111 callback.element(tag, "", depth);
112 for (std::list<info>::const_iterator it = l.begin(),
113 end = l.end(); it != end; ++it)
114 {
115 boost::apply_visitor(
116 this_type(callback, it->tag, depth+1), it->value);
117 }
118 }
119
120 Callback& callback;
121 utf8_string const& tag;
122 int depth;
123 };
124
125 // bare-bones print support
126 template <typename Out>
127 struct simple_printer
128 {
129 typedef utf8_string string;
130
131 simple_printer(Out& out_)
132 : out(out_) {}
133
134 void element(string const& tag, string const& value, int /*depth*/) const
135 {
136 if (value.empty())
137 out << '<' << tag << '>';
138 else
139 out << '"' << value << '"';
140 }
141
142 Out& out;
143 };
144#ifdef _MSC_VER
145# pragma warning(pop)
146#endif
147
148 template <typename Out>
149 Out& operator<<(Out& out, info const& what)
150 {
151 simple_printer<Out> pr(out);
152 basic_info_walker<simple_printer<Out> > walker(pr, what.tag, 0);
153 boost::apply_visitor(walker, what.value);
154 return out;
155 }
156}}
157
158#endif
159