1
2#ifndef DATE_TIME_SPECIAL_VALUES_PARSER_HPP__
3#define DATE_TIME_SPECIAL_VALUES_PARSER_HPP__
4
5/* Copyright (c) 2005 CrystalClear Software, Inc.
6 * Use, modification and distribution is subject to the
7 * Boost Software License, Version 1.0. (See accompanying
8 * file LICENSE_1_0.txt or http://www.boost.org/LICENSE_1_0.txt)
9 * Author: Jeff Garland, Bart Garst
10 * $Date:
11 */
12
13
14#include "boost/date_time/string_parse_tree.hpp"
15#include "boost/date_time/special_defs.hpp"
16#include <string>
17#include <vector>
18
19namespace boost { namespace date_time {
20
21 //! Class for special_value parsing
22 /*!
23 * TODO: add doc-comments for which elements can be changed
24 * Parses input stream for strings representing special_values.
25 * Special values parsed are:
26 * - not_a_date_time
27 * - neg_infin
28 * - pod_infin
29 * - min_date_time
30 * - max_date_time
31 */
32 template<class date_type, typename charT>
33 class special_values_parser
34 {
35 public:
36 typedef std::basic_string<charT> string_type;
37 //typedef std::basic_stringstream<charT> stringstream_type;
38 typedef std::istreambuf_iterator<charT> stream_itr_type;
39 //typedef typename string_type::const_iterator const_itr;
40 //typedef typename date_type::year_type year_type;
41 //typedef typename date_type::month_type month_type;
42 typedef typename date_type::duration_type duration_type;
43 //typedef typename date_type::day_of_week_type day_of_week_type;
44 //typedef typename date_type::day_type day_type;
45 typedef string_parse_tree<charT> parse_tree_type;
46 typedef typename parse_tree_type::parse_match_result_type match_results;
47 typedef std::vector<std::basic_string<charT> > collection_type;
48
49 typedef charT char_type;
50 static const char_type nadt_string[16];
51 static const char_type neg_inf_string[10];
52 static const char_type pos_inf_string[10];
53 static const char_type min_date_time_string[18];
54 static const char_type max_date_time_string[18];
55
56 //! Creates a special_values_parser with the default set of "sv_strings"
57 special_values_parser()
58 {
59 sv_strings(nadt_str: string_type(nadt_string),
60 neg_inf_str: string_type(neg_inf_string),
61 pos_inf_str: string_type(pos_inf_string),
62 min_dt_str: string_type(min_date_time_string),
63 max_dt_str: string_type(max_date_time_string));
64 }
65
66 //! Creates a special_values_parser using a user defined set of element strings
67 special_values_parser(const string_type& nadt_str,
68 const string_type& neg_inf_str,
69 const string_type& pos_inf_str,
70 const string_type& min_dt_str,
71 const string_type& max_dt_str)
72 {
73 sv_strings(nadt_str, neg_inf_str, pos_inf_str, min_dt_str, max_dt_str);
74 }
75
76 special_values_parser(typename collection_type::iterator beg, typename collection_type::iterator end)
77 {
78 collection_type phrases;
79 std::copy(beg, end, std::back_inserter(phrases));
80 m_sv_strings = parse_tree_type(phrases, static_cast<int>(not_a_date_time));
81 }
82
83 special_values_parser(const special_values_parser<date_type,charT>& svp)
84 {
85 this->m_sv_strings = svp.m_sv_strings;
86 }
87
88 //! Replace special value strings
89 void sv_strings(const string_type& nadt_str,
90 const string_type& neg_inf_str,
91 const string_type& pos_inf_str,
92 const string_type& min_dt_str,
93 const string_type& max_dt_str)
94 {
95 collection_type phrases;
96 phrases.push_back(nadt_str);
97 phrases.push_back(neg_inf_str);
98 phrases.push_back(pos_inf_str);
99 phrases.push_back(min_dt_str);
100 phrases.push_back(max_dt_str);
101 m_sv_strings = parse_tree_type(phrases, static_cast<int>(not_a_date_time));
102 }
103
104 /* Does not return a special_value because if the parsing fails,
105 * the return value will always be not_a_date_time
106 * (mr.current_match retains its default value of -1 on a failed
107 * parse and that casts to not_a_date_time). */
108 //! Sets match_results.current_match to the corresponding special_value or -1
109 bool match(stream_itr_type& sitr,
110 stream_itr_type& str_end,
111 match_results& mr) const
112 {
113 unsigned int level = 0;
114 m_sv_strings.match(sitr, str_end, mr, level);
115 return (mr.current_match != match_results::PARSE_ERROR);
116 }
117 /*special_values match(stream_itr_type& sitr,
118 stream_itr_type& str_end,
119 match_results& mr) const
120 {
121 unsigned int level = 0;
122 m_sv_strings.match(sitr, str_end, mr, level);
123 if(mr.current_match == match_results::PARSE_ERROR) {
124 throw std::ios_base::failure("Parse failed. No match found for '" + mr.cache + "'");
125 }
126 return static_cast<special_values>(mr.current_match);
127 }*/
128
129
130 private:
131 parse_tree_type m_sv_strings;
132
133 };
134
135 template<class date_type, class CharT>
136 const typename special_values_parser<date_type, CharT>::char_type
137 special_values_parser<date_type, CharT>::nadt_string[16] =
138 {'n','o','t','-','a','-','d','a','t','e','-','t','i','m','e'};
139 template<class date_type, class CharT>
140 const typename special_values_parser<date_type, CharT>::char_type
141 special_values_parser<date_type, CharT>::neg_inf_string[10] =
142 {'-','i','n','f','i','n','i','t','y'};
143 template<class date_type, class CharT>
144 const typename special_values_parser<date_type, CharT>::char_type
145 special_values_parser<date_type, CharT>::pos_inf_string[10] =
146 {'+','i','n','f','i','n','i','t','y'};
147 template<class date_type, class CharT>
148 const typename special_values_parser<date_type, CharT>::char_type
149 special_values_parser<date_type, CharT>::min_date_time_string[18] =
150 {'m','i','n','i','m','u','m','-','d','a','t','e','-','t','i','m','e'};
151 template<class date_type, class CharT>
152 const typename special_values_parser<date_type, CharT>::char_type
153 special_values_parser<date_type, CharT>::max_date_time_string[18] =
154 {'m','a','x','i','m','u','m','-','d','a','t','e','-','t','i','m','e'};
155
156} } //namespace
157
158#endif // DATE_TIME_SPECIAL_VALUES_PARSER_HPP__
159
160

source code of boost/boost/date_time/special_values_parser.hpp