1/*=============================================================================
2 Copyright (c) 2001-2011 Joel de Guzman
3 Copyright (c) 2001-2011 Hartmut Kaiser
4 Copyright (c) 2014 Thomas Bernard
5
6 Distributed under the Boost Software License, Version 1.0. (See accompanying
7 file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
8==============================================================================*/
9#ifndef BOOST_SPIRIT_X3_DIRECTIVE_REPEAT_HPP
10#define BOOST_SPIRIT_X3_DIRECTIVE_REPEAT_HPP
11
12#include <boost/spirit/home/x3/core/parser.hpp>
13#include <boost/spirit/home/x3/operator/kleene.hpp>
14
15namespace boost { namespace spirit { namespace x3 { namespace detail
16{
17 template <typename T>
18 struct exact_count // handles repeat(exact)[p]
19 {
20 typedef T type;
21 bool got_max(T i) const { return i >= exact_value; }
22 bool got_min(T i) const { return i >= exact_value; }
23
24 T const exact_value;
25 };
26
27 template <typename T>
28 struct finite_count // handles repeat(min, max)[p]
29 {
30 typedef T type;
31 bool got_max(T i) const { return i >= max_value; }
32 bool got_min(T i) const { return i >= min_value; }
33
34 T const min_value;
35 T const max_value;
36 };
37
38 template <typename T>
39 struct infinite_count // handles repeat(min, inf)[p]
40 {
41 typedef T type;
42 bool got_max(T /*i*/) const { return false; }
43 bool got_min(T i) const { return i >= min_value; }
44
45 T const min_value;
46 };
47}}}}
48
49namespace boost { namespace spirit { namespace x3
50{
51 template<typename Subject, typename RepeatCountLimit>
52 struct repeat_directive : unary_parser<Subject, repeat_directive<Subject,RepeatCountLimit>>
53 {
54 typedef unary_parser<Subject, repeat_directive<Subject,RepeatCountLimit>> base_type;
55 static bool const is_pass_through_unary = true;
56 static bool const handles_container = true;
57
58 constexpr repeat_directive(Subject const& subject, RepeatCountLimit const& repeat_limit_)
59 : base_type(subject)
60 , repeat_limit(repeat_limit_)
61 {}
62
63 template<typename Iterator, typename Context
64 , typename RContext, typename Attribute>
65 bool parse(
66 Iterator& first, Iterator const& last
67 , Context const& context, RContext& rcontext, Attribute& attr) const
68 {
69 Iterator local_iterator = first;
70 typename RepeatCountLimit::type i{};
71 for (/**/; !repeat_limit.got_min(i); ++i)
72 {
73 if (!detail::parse_into_container(
74 this->subject, local_iterator, last, context, rcontext, attr))
75 return false;
76 }
77
78 first = local_iterator;
79 // parse some more up to the maximum specified
80 for (/**/; !repeat_limit.got_max(i); ++i)
81 {
82 if (!detail::parse_into_container(
83 this->subject, first, last, context, rcontext, attr))
84 break;
85 }
86 return true;
87 }
88
89 RepeatCountLimit repeat_limit;
90 };
91
92 // Infinite loop tag type
93 struct inf_type {};
94 constexpr inf_type inf = inf_type();
95
96 struct repeat_gen
97 {
98 template<typename Subject>
99 constexpr auto operator[](Subject const& subject) const
100 {
101 return *as_parser(subject);
102 }
103
104 template <typename T>
105 struct repeat_gen_lvl1
106 {
107 constexpr repeat_gen_lvl1(T&& repeat_limit_)
108 : repeat_limit(repeat_limit_)
109 {}
110
111 template<typename Subject>
112 constexpr repeat_directive< typename extension::as_parser<Subject>::value_type, T>
113 operator[](Subject const& subject) const
114 {
115 return { as_parser(subject),repeat_limit };
116 }
117
118 T repeat_limit;
119 };
120
121 template <typename T>
122 constexpr repeat_gen_lvl1<detail::exact_count<T>>
123 operator()(T const exact) const
124 {
125 return { detail::exact_count<T>{exact} };
126 }
127
128 template <typename T>
129 constexpr repeat_gen_lvl1<detail::finite_count<T>>
130 operator()(T const min_val, T const max_val) const
131 {
132 return { detail::finite_count<T>{min_val,max_val} };
133 }
134
135 template <typename T>
136 constexpr repeat_gen_lvl1<detail::infinite_count<T>>
137 operator()(T const min_val, inf_type const &) const
138 {
139 return { detail::infinite_count<T>{min_val} };
140 }
141 };
142
143 constexpr auto repeat = repeat_gen{};
144}}}
145
146namespace boost { namespace spirit { namespace x3 { namespace traits
147{
148 template <typename Subject, typename RepeatCountLimit, typename Context>
149 struct attribute_of<x3::repeat_directive<Subject,RepeatCountLimit>, Context>
150 : build_container<typename attribute_of<Subject, Context>::type> {};
151}}}}
152
153
154#endif
155

source code of boost/libs/spirit/include/boost/spirit/home/x3/directive/repeat.hpp