1 /*=============================================================================
2     Copyright (c) 2001-2011 Joel de Guzman
3     Copyright (c) 2001-2011 Hartmut Kaiser
4 
5     Distributed under the Boost Software License, Version 1.0. (See accompanying
6     file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
7 =============================================================================*/
8 #if !defined(SPIRIT_LIST_MARCH_24_2007_1031AM)
9 #define SPIRIT_LIST_MARCH_24_2007_1031AM
10 
11 #if defined(_MSC_VER)
12 #pragma once
13 #endif
14 
15 #include <boost/spirit/home/qi/meta_compiler.hpp>
16 #include <boost/spirit/home/qi/parser.hpp>
17 #include <boost/spirit/home/support/container.hpp>
18 #include <boost/spirit/home/qi/detail/attributes.hpp>
19 #include <boost/spirit/home/qi/detail/fail_function.hpp>
20 #include <boost/spirit/home/qi/detail/pass_container.hpp>
21 #include <boost/spirit/home/support/has_semantic_action.hpp>
22 #include <boost/spirit/home/support/handles_container.hpp>
23 #include <boost/spirit/home/support/info.hpp>
24 #include <vector>
25 
26 namespace boost { namespace spirit
27 {
28     ///////////////////////////////////////////////////////////////////////////
29     // Enablers
30     ///////////////////////////////////////////////////////////////////////////
31     template <>
32     struct use_operator<qi::domain, proto::tag::modulus> // enables p % d
33       : mpl::true_ {};
34 }}
35 
36 namespace boost { namespace spirit { namespace qi
37 {
38     template <typename Left, typename Right>
39     struct list : binary_parser<list<Left, Right> >
40     {
41         typedef Left left_type;
42         typedef Right right_type;
43 
44         template <typename Context, typename Iterator>
45         struct attribute
46         {
47             // Build a std::vector from the LHS's attribute. Note
48             // that build_std_vector may return unused_type if the
49             // subject's attribute is an unused_type.
50             typedef typename
51                 traits::build_std_vector<
52                     typename traits::
53                         attribute_of<Left, Context, Iterator>::type
54                 >::type
55             type;
56         };
57 
listboost::spirit::qi::list58         list(Left const& left_, Right const& right_)
59           : left(left_), right(right_) {}
60 
61         template <typename F>
parse_containerboost::spirit::qi::list62         bool parse_container(F f) const
63         {
64             // in order to succeed we need to match at least one element
65             if (f (left))
66                 return false;
67 
68             typename F::iterator_type save = f.f.first;
69             while (right.parse(f.f.first, f.f.last, f.f.context, f.f.skipper, unused)
70               && !f (left))
71             {
72                 save = f.f.first;
73             }
74 
75             f.f.first = save;
76             return true;
77         }
78 
79         template <typename Iterator, typename Context
80           , typename Skipper, typename Attribute>
parseboost::spirit::qi::list81         bool parse(Iterator& first, Iterator const& last
82           , Context& context, Skipper const& skipper
83           , Attribute& attr_) const
84         {
85             typedef detail::fail_function<Iterator, Context, Skipper>
86                 fail_function;
87 
88             // ensure the attribute is actually a container type
89             traits::make_container(attr_);
90 
91             Iterator iter = first;
92             fail_function f(iter, last, context, skipper);
93             if (!parse_container(detail::make_pass_container(f, attr_)))
94                 return false;
95 
96             first = f.first;
97             return true;
98         }
99 
100         template <typename Context>
whatboost::spirit::qi::list101         info what(Context& context) const
102         {
103             return info("list",
104                 std::make_pair(left.what(context), right.what(context)));
105         }
106 
107         Left left;
108         Right right;
109     };
110 
111     ///////////////////////////////////////////////////////////////////////////
112     // Parser generators: make_xxx function (objects)
113     ///////////////////////////////////////////////////////////////////////////
114     template <typename Elements, typename Modifiers>
115     struct make_composite<proto::tag::modulus, Elements, Modifiers>
116       : make_binary_composite<Elements, list>
117     {};
118 }}}
119 
120 namespace boost { namespace spirit { namespace traits
121 {
122     ///////////////////////////////////////////////////////////////////////////
123     template <typename Left, typename Right>
124     struct has_semantic_action<qi::list<Left, Right> >
125       : binary_has_semantic_action<Left, Right> {};
126 
127     ///////////////////////////////////////////////////////////////////////////
128     template <typename Left, typename Right, typename Attribute
129       , typename Context, typename Iterator>
130     struct handles_container<qi::list<Left, Right>, Attribute, Context
131           , Iterator>
132       : mpl::true_ {};
133 }}}
134 
135 #endif
136