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