boost/date_time/date_facet.hpp

   1 #ifndef _DATE_TIME_DATE_FACET__HPP___
   2 #define _DATE_TIME_DATE_FACET__HPP___
   3
   4 /* Copyright (c) 2004-2005 CrystalClear Software, Inc.
   5  * Use, modification and distribution is subject to the
   6  * Boost Software License, Version 1.0. (See accompanying
   7  * file LICENSE_1_0.txt or http://www.boost.org/LICENSE_1_0.txt)
   8  * Author:  Martin Andrian, Jeff Garland, Bart Garst
   9  * $Date$
  10  */
  11
  12 #include <locale>
  13 #include <string>
  14 #include <vector>
  15 #include <iterator> // ostreambuf_iterator
  16 #include <boost/throw_exception.hpp>
  17 #include <boost/algorithm/string/replace.hpp>
  18 #include <boost/date_time/compiler_config.hpp>
  19 #include <boost/date_time/period.hpp>
  20 #include <boost/date_time/special_defs.hpp>
  21 #include <boost/date_time/special_values_formatter.hpp>
  22 #include <boost/date_time/period_formatter.hpp>
  23 #include <boost/date_time/period_parser.hpp>
  24 #include <boost/date_time/date_generator_formatter.hpp>
  25 #include <boost/date_time/date_generator_parser.hpp>
  26 #include <boost/date_time/format_date_parser.hpp>
  27
  28 namespace boost { namespace date_time {
  29
  30
  31   /*! Class that provides format based I/O facet for date types.
  32    *
  33    * This class allows the formatting of dates by using format string.
  34    * Format strings are:
  35    *
  36    *  - %A => long_weekday_format - Full name Ex: Tuesday
  37    *  - %a => short_weekday_format - Three letter abbreviation Ex: Tue
  38    *  - %B => long_month_format - Full name Ex: October
  39    *  - %b => short_month_format - Three letter abbreviation Ex: Oct
  40    *  - %x => standard_format_specifier - defined by the locale
  41    *  - %Y-%b-%d => default_date_format - YYYY-Mon-dd
  42    *
  43    * Default month format == %b
  44    * Default weekday format == %a
  45    */
  46   template <class date_type,
  47             class CharT,
  48             class OutItrT = std::ostreambuf_iterator<CharT, std::char_traits<CharT> > >
  49   class date_facet : public std::locale::facet {
  50   public:
  51     typedef typename date_type::duration_type duration_type;
  52     // greg_weekday is gregorian_calendar::day_of_week_type
  53     typedef typename date_type::day_of_week_type day_of_week_type;
  54     typedef typename date_type::day_type day_type;
  55     typedef typename date_type::month_type month_type;
  56     typedef boost::date_time::period<date_type,duration_type> period_type;
  57     typedef std::basic_string<CharT> string_type;
  58     typedef CharT                    char_type;
  59     typedef boost::date_time::period_formatter<CharT>  period_formatter_type;
  60     typedef boost::date_time::special_values_formatter<CharT>  special_values_formatter_type;
  61     typedef std::vector<std::basic_string<CharT> > input_collection_type;
  62     // used for the output of the date_generators
  63     typedef date_generator_formatter<date_type, CharT> date_gen_formatter_type;
  64     typedef partial_date<date_type>          partial_date_type;
  65     typedef nth_kday_of_month<date_type>     nth_kday_type;
  66     typedef first_kday_of_month<date_type>   first_kday_type;
  67     typedef last_kday_of_month<date_type>    last_kday_type;
  68     typedef first_kday_after<date_type>      kday_after_type;
  69     typedef first_kday_before<date_type>     kday_before_type;
  70     static const char_type long_weekday_format[3];
  71     static const char_type short_weekday_format[3];
  72     static const char_type long_month_format[3];
  73     static const char_type short_month_format[3];
  74     static const char_type default_period_separator[4];
  75     static const char_type standard_format_specifier[3];
  76     static const char_type iso_format_specifier[7];
  77     static const char_type iso_format_extended_specifier[9];
  78     static const char_type default_date_format[9]; // YYYY-Mon-DD
  79     static std::locale::id id;
  80
  81 #if defined (__SUNPRO_CC) && defined (_RWSTD_VER)
  82       std::locale::id& __get_id (void) const { return id; }
  83 #endif
  84
  85     explicit date_facet(::size_t a_ref = 0)
  86       : std::locale::facet(a_ref),
  87         //m_format(standard_format_specifier)
  88         m_format(default_date_format),
  89         m_month_format(short_month_format),
  90         m_weekday_format(short_weekday_format)
  91     {}
  92
  93     explicit date_facet(const char_type* format_str,
  94                         const input_collection_type& short_names,
  95                         ::size_t ref_count = 0)
  96       : std::locale::facet(ref_count),
  97         m_format(format_str),
  98         m_month_format(short_month_format),
  99         m_weekday_format(short_weekday_format),
 100         m_month_short_names(short_names)
 101     {}
 102
 103
 104     explicit date_facet(const char_type* format_str,
 105                         period_formatter_type per_formatter = period_formatter_type(),
 106                         special_values_formatter_type sv_formatter = special_values_formatter_type(),
 107                         date_gen_formatter_type dg_formatter = date_gen_formatter_type(),
 108                         ::size_t ref_count = 0)
 109       : std::locale::facet(ref_count),
 110         m_format(format_str),
 111         m_month_format(short_month_format),
 112         m_weekday_format(short_weekday_format),
 113         m_period_formatter(per_formatter),
 114         m_date_gen_formatter(dg_formatter),
 115         m_special_values_formatter(sv_formatter)
 116      {}
 117     void format(const char_type* const format_str) {
 118       m_format = format_str;
 119     }
 120     virtual void set_iso_format()
 121     {
 122       m_format = iso_format_specifier;
 123     }
 124     virtual void set_iso_extended_format()
 125     {
 126       m_format = iso_format_extended_specifier;
 127     }
 128     void month_format(const char_type* const format_str) {
 129       m_month_format = format_str;
 130     }
 131     void weekday_format(const char_type* const format_str) {
 132       m_weekday_format = format_str;
 133     }
 134
 135     void period_formatter(period_formatter_type per_formatter) {
 136       m_period_formatter= per_formatter;
 137     }
 138     void special_values_formatter(const special_values_formatter_type& svf)
 139     {
 140       m_special_values_formatter = svf;
 141     }
 142     void short_weekday_names(const input_collection_type& short_names)
 143     {
 144       m_weekday_short_names = short_names;
 145     }
 146     void long_weekday_names(const input_collection_type& long_names)
 147     {
 148       m_weekday_long_names = long_names;
 149     }
 150
 151     void short_month_names(const input_collection_type& short_names)
 152     {
 153       m_month_short_names = short_names;
 154     }
 155
 156     void long_month_names(const input_collection_type& long_names)
 157     {
 158       m_month_long_names = long_names;
 159     }
 160
 161     void date_gen_phrase_strings(const input_collection_type& new_strings,
 162                            typename date_gen_formatter_type::phrase_elements beg_pos=date_gen_formatter_type::first)
 163     {
 164       m_date_gen_formatter.elements(new_strings, beg_pos);
 165     }
 166
 167     OutItrT put(OutItrT next,
 168                 std::ios_base& a_ios,
 169                 char_type fill_char,
 170                 const date_type& d) const
 171     {
 172       if (d.is_special()) {
 173         return do_put_special(next, a_ios, fill_char, d.as_special());
 174       }
 175       //The following line of code required the date to support a to_tm function
 176       return do_put_tm(next, a_ios, fill_char, to_tm(d), m_format);
 177     }
 178
 179     OutItrT put(OutItrT next,
 180                 std::ios_base& a_ios,
 181                 char_type fill_char,
 182                 const duration_type& dd) const
 183     {
 184       if (dd.is_special()) {
 185         return do_put_special(next, a_ios, fill_char, dd.get_rep().as_special());
 186       }
 187
 188       typedef std::num_put<CharT, OutItrT> num_put;
 189       if (std::has_facet<num_put>(a_ios.getloc())) {
 190         return std::use_facet<num_put>(a_ios.getloc()).put(next, a_ios, fill_char, dd.get_rep().as_number());
 191       }
 192       else {
 193         num_put* f = new num_put();
 194         std::locale l = std::locale(a_ios.getloc(), f);
 195         a_ios.imbue(l);
 196         return f->put(next, a_ios, fill_char, dd.get_rep().as_number());
 197       }
 198
 199     }
 200
 201
 202     OutItrT put(OutItrT next,
 203                 std::ios_base& a_ios,
 204                 char_type fill_char,
 205                 const month_type& m) const
 206     {
 207       //if (d.is_special()) {
 208       //  return do_put_special(next, a_ios, fill_char, d.as_special());
 209       //}
 210       //The following line of code required the date to support a to_tm function
 211       tm dtm;
 212       init_tm(dtm);
 213       dtm.tm_mon = m -1;
 214       return do_put_tm(next, a_ios, fill_char, dtm, m_month_format);
 215     }
 216
 217     //! puts the day of month
 218     OutItrT put(OutItrT next,
 219                 std::ios_base& a_ios,
 220                 char_type fill_char,
 221                 const day_type& day) const
 222     {
 223       tm dtm;
 224       init_tm(dtm);
 225       dtm.tm_mday = day.as_number();
 226       char_type tmp[3] = {'%','d'};
 227       string_type temp_format(tmp);
 228       return do_put_tm(next, a_ios, fill_char, dtm, temp_format);
 229     }
 230
 231     OutItrT put(OutItrT next,
 232                 std::ios_base& a_ios,
 233                 char_type fill_char,
 234                 const day_of_week_type& dow) const
 235     {
 236       //if (d.is_special()) {
 237       //  return do_put_special(next, a_ios, fill_char, d.as_special());
 238       //}
 239       //The following line of code required the date to support a to_tm function
 240       tm dtm;
 241       init_tm(dtm);
 242       dtm.tm_wday = dow;
 243       return do_put_tm(next, a_ios, fill_char, dtm, m_weekday_format);
 244     }
 245
 246
 247     OutItrT put(OutItrT next,
 248                 std::ios_base& a_ios,
 249                 char_type fill_char,
 250                 const period_type& p) const
 251     {
 252       return m_period_formatter.put_period(next, a_ios, fill_char, p, *this);
 253     }
 254
 255     OutItrT put(OutItrT next,
 256                 std::ios_base& a_ios,
 257                 char_type fill_char,
 258                 const partial_date_type& pd) const
 259     {
 260       return m_date_gen_formatter.put_partial_date(next, a_ios, fill_char, pd, *this);
 261     }
 262
 263     OutItrT put(OutItrT next,
 264                 std::ios_base& a_ios,
 265                 char_type fill_char,
 266                 const nth_kday_type& nkd) const
 267     {
 268       return m_date_gen_formatter.put_nth_kday(next, a_ios, fill_char, nkd, *this);
 269     }
 270
 271     OutItrT put(OutItrT next,
 272                 std::ios_base& a_ios,
 273                 char_type fill_char,
 274                 const first_kday_type& fkd) const
 275     {
 276       return m_date_gen_formatter.put_first_kday(next, a_ios, fill_char, fkd, *this);
 277     }
 278
 279     OutItrT put(OutItrT next,
 280                 std::ios_base& a_ios,
 281                 char_type fill_char,
 282                 const last_kday_type& lkd) const
 283     {
 284       return m_date_gen_formatter.put_last_kday(next, a_ios, fill_char, lkd, *this);
 285     }
 286
 287     OutItrT put(OutItrT next,
 288                 std::ios_base& a_ios,
 289                 char_type fill_char,
 290                 const kday_before_type& fkb) const
 291     {
 292       return m_date_gen_formatter.put_kday_before(next, a_ios, fill_char, fkb, *this);
 293     }
 294
 295     OutItrT put(OutItrT next,
 296                 std::ios_base& a_ios,
 297                 char_type fill_char,
 298                 const kday_after_type& fka) const
 299     {
 300       return m_date_gen_formatter.put_kday_after(next, a_ios, fill_char, fka, *this);
 301     }
 302
 303   protected:
 304     //! Helper function to initialize all fields in a tm struct
 305     tm init_tm(tm& tm_value) const
 306     {
 307       tm_value.tm_sec = 0;         /* seconds */
 308       tm_value.tm_min = 0;         /* minutes */
 309       tm_value.tm_hour = 0;        /* hours */
 310       tm_value.tm_mday = 0;        /* day of the month */
 311       tm_value.tm_mon = 0;         /* month */
 312       tm_value.tm_year = 0;        /* year */
 313       tm_value.tm_wday = 0;        /* day of the week */
 314       tm_value.tm_yday = 0;        /* day in the year */
 315       tm_value.tm_isdst = 0;       /* daylight saving time */
 316       return tm_value;
 317     }
 318     virtual OutItrT do_put_special(OutItrT next,
 319                                    std::ios_base& /*a_ios*/,
 320                                    char_type /*fill_char*/,
 321                                    const boost::date_time::special_values sv) const
 322     {
 323       m_special_values_formatter.put_special(next, sv);
 324       return next;
 325     }
 326     virtual OutItrT do_put_tm(OutItrT next,
 327                               std::ios_base& a_ios,
 328                               char_type fill_char,
 329                               const tm& tm_value,
 330                               string_type a_format) const
 331     {
 332       // update format string with custom names
 333       if (m_weekday_long_names.size()) {
 334         boost::algorithm::replace_all(a_format,
 335                                       long_weekday_format,
 336                                       m_weekday_long_names[tm_value.tm_wday]);
 337       }
 338       if (m_weekday_short_names.size()) {
 339         boost::algorithm::replace_all(a_format,
 340                                       short_weekday_format,
 341                                       m_weekday_short_names[tm_value.tm_wday]);
 342
 343       }
 344       if (m_month_long_names.size()) {
 345         boost::algorithm::replace_all(a_format,
 346                                       long_month_format,
 347                                       m_month_long_names[tm_value.tm_mon]);
 348       }
 349       if (m_month_short_names.size()) {
 350         boost::algorithm::replace_all(a_format,
 351                                       short_month_format,
 352                                       m_month_short_names[tm_value.tm_mon]);
 353       }
 354       // use time_put facet to create final string
 355       const char_type* p_format = a_format.c_str();
 356       return std::use_facet<std::time_put<CharT> >(a_ios.getloc()).put(next, a_ios,
 357                                                                        fill_char,
 358                                                                        &tm_value,
 359                                                                        p_format,
 360                                                                        p_format + a_format.size());
 361     }
 362   protected:
 363     string_type                   m_format;
 364     string_type                   m_month_format;
 365     string_type                   m_weekday_format;
 366     period_formatter_type         m_period_formatter;
 367     date_gen_formatter_type       m_date_gen_formatter;
 368     special_values_formatter_type m_special_values_formatter;
 369     input_collection_type         m_month_short_names;
 370     input_collection_type         m_month_long_names;
 371     input_collection_type         m_weekday_short_names;
 372     input_collection_type         m_weekday_long_names;
 373   private:
 374   };
 375
 376   template <class date_type, class CharT, class OutItrT>
 377   std::locale::id date_facet<date_type, CharT, OutItrT>::id;
 378
 379   template <class date_type, class CharT, class OutItrT>
 380   const typename date_facet<date_type, CharT, OutItrT>::char_type
 381   date_facet<date_type, CharT, OutItrT>::long_weekday_format[3] = {'%','A'};
 382
 383   template <class date_type, class CharT, class OutItrT>
 384   const typename date_facet<date_type, CharT, OutItrT>::char_type
 385   date_facet<date_type, CharT, OutItrT>::short_weekday_format[3] = {'%','a'};
 386
 387   template <class date_type, class CharT, class OutItrT>
 388   const typename date_facet<date_type, CharT, OutItrT>::char_type
 389   date_facet<date_type, CharT, OutItrT>::long_month_format[3] = {'%','B'};
 390
 391   template <class date_type, class CharT, class OutItrT>
 392   const typename date_facet<date_type, CharT, OutItrT>::char_type
 393   date_facet<date_type, CharT, OutItrT>::short_month_format[3] = {'%','b'};
 394
 395   template <class date_type, class CharT, class OutItrT>
 396   const typename date_facet<date_type, CharT, OutItrT>::char_type
 397   date_facet<date_type, CharT, OutItrT>::default_period_separator[4] = { ' ', '/', ' '};
 398
 399   template <class date_type, class CharT, class OutItrT>
 400   const typename date_facet<date_type, CharT, OutItrT>::char_type
 401   date_facet<date_type, CharT, OutItrT>::standard_format_specifier[3] =
 402     {'%', 'x' };
 403
 404   template <class date_type, class CharT, class OutItrT>
 405   const typename date_facet<date_type, CharT, OutItrT>::char_type
 406   date_facet<date_type, CharT, OutItrT>::iso_format_specifier[7] =
 407     {'%', 'Y', '%', 'm', '%', 'd' };
 408
 409   template <class date_type, class CharT, class OutItrT>
 410   const typename date_facet<date_type, CharT, OutItrT>::char_type
 411   date_facet<date_type, CharT, OutItrT>::iso_format_extended_specifier[9] =
 412     {'%', 'Y', '-', '%', 'm', '-', '%', 'd' };
 413
 414   template <class date_type, class CharT, class OutItrT>
 415   const typename date_facet<date_type, CharT, OutItrT>::char_type
 416   date_facet<date_type, CharT, OutItrT>::default_date_format[9] =
 417     {'%','Y','-','%','b','-','%','d'};
 418
 419
 420
 421   //! Input facet
 422   template <class date_type,
 423             class CharT,
 424             class InItrT = std::istreambuf_iterator<CharT, std::char_traits<CharT> > >
 425   class date_input_facet : public std::locale::facet {
 426   public:
 427     typedef typename date_type::duration_type duration_type;
 428     // greg_weekday is gregorian_calendar::day_of_week_type
 429     typedef typename date_type::day_of_week_type day_of_week_type;
 430     typedef typename date_type::day_type day_type;
 431     typedef typename date_type::month_type month_type;
 432     typedef typename date_type::year_type year_type;
 433     typedef boost::date_time::period<date_type,duration_type> period_type;
 434     typedef std::basic_string<CharT> string_type;
 435     typedef CharT                    char_type;
 436     typedef boost::date_time::period_parser<date_type, CharT>  period_parser_type;
 437     typedef boost::date_time::special_values_parser<date_type,CharT> special_values_parser_type;
 438     typedef std::vector<std::basic_string<CharT> > input_collection_type;
 439     typedef format_date_parser<date_type, CharT> format_date_parser_type;
 440     // date_generators stuff goes here
 441     typedef date_generator_parser<date_type, CharT> date_gen_parser_type;
 442     typedef partial_date<date_type>          partial_date_type;
 443     typedef nth_kday_of_month<date_type>     nth_kday_type;
 444     typedef first_kday_of_month<date_type>   first_kday_type;
 445     typedef last_kday_of_month<date_type>    last_kday_type;
 446     typedef first_kday_after<date_type>      kday_after_type;
 447     typedef first_kday_before<date_type>     kday_before_type;
 448
 449     static const char_type long_weekday_format[3];
 450     static const char_type short_weekday_format[3];
 451     static const char_type long_month_format[3];
 452     static const char_type short_month_format[3];
 453     static const char_type four_digit_year_format[3];
 454     static const char_type two_digit_year_format[3];
 455     static const char_type default_period_separator[4];
 456     static const char_type standard_format_specifier[3];
 457     static const char_type iso_format_specifier[7];
 458     static const char_type iso_format_extended_specifier[9];
 459     static const char_type default_date_format[9]; // YYYY-Mon-DD
 460     static std::locale::id id;
 461
 462     explicit date_input_facet(::size_t a_ref = 0)
 463       : std::locale::facet(a_ref),
 464         m_format(default_date_format),
 465         m_month_format(short_month_format),
 466         m_weekday_format(short_weekday_format),
 467         m_year_format(four_digit_year_format),
 468         m_parser(m_format, std::locale::classic())
 469         // default period_parser & special_values_parser used
 470     {}
 471
 472     explicit date_input_facet(const string_type& format_str,
 473                               ::size_t a_ref = 0)
 474       : std::locale::facet(a_ref),
 475         m_format(format_str),
 476         m_month_format(short_month_format),
 477         m_weekday_format(short_weekday_format),
 478         m_year_format(four_digit_year_format),
 479         m_parser(m_format, std::locale::classic())
 480         // default period_parser & special_values_parser used
 481     {}
 482
 483     explicit date_input_facet(const string_type& format_str,
 484                               const format_date_parser_type& date_parser,
 485                               const special_values_parser_type& sv_parser,
 486                               const period_parser_type& per_parser,
 487                               const date_gen_parser_type& date_gen_parser,
 488                               ::size_t ref_count = 0)
 489       : std::locale::facet(ref_count),
 490         m_format(format_str),
 491         m_month_format(short_month_format),
 492         m_weekday_format(short_weekday_format),
 493         m_year_format(four_digit_year_format),
 494         m_parser(date_parser),
 495         m_date_gen_parser(date_gen_parser),
 496         m_period_parser(per_parser),
 497         m_sv_parser(sv_parser)
 498     {}
 499
 500
 501     void format(const char_type* const format_str) {
 502       m_format = format_str;
 503     }
 504     virtual void set_iso_format()
 505     {
 506       m_format = iso_format_specifier;
 507     }
 508     virtual void set_iso_extended_format()
 509     {
 510       m_format = iso_format_extended_specifier;
 511     }
 512     void month_format(const char_type* const format_str) {
 513       m_month_format = format_str;
 514     }
 515     void weekday_format(const char_type* const format_str) {
 516       m_weekday_format = format_str;
 517     }
 518     void year_format(const char_type* const format_str) {
 519       m_year_format = format_str;
 520     }
 521
 522     void period_parser(period_parser_type per_parser) {
 523       m_period_parser = per_parser;
 524     }
 525     void short_weekday_names(const input_collection_type& weekday_names)
 526     {
 527       m_parser.short_weekday_names(weekday_names);
 528     }
 529     void long_weekday_names(const input_collection_type& weekday_names)
 530     {
 531       m_parser.long_weekday_names(weekday_names);
 532     }
 533
 534     void short_month_names(const input_collection_type& month_names)
 535     {
 536       m_parser.short_month_names(month_names);
 537     }
 538
 539     void long_month_names(const input_collection_type& month_names)
 540     {
 541       m_parser.long_month_names(month_names);
 542     }
 543
 544     void date_gen_element_strings(const input_collection_type& col)
 545     {
 546       m_date_gen_parser.element_strings(col);
 547     }
 548     void date_gen_element_strings(const string_type& first,
 549                                   const string_type& second,
 550                                   const string_type& third,
 551                                   const string_type& fourth,
 552                                   const string_type& fifth,
 553                                   const string_type& last,
 554                                   const string_type& before,
 555                                   const string_type& after,
 556                                   const string_type& of)
 557
 558     {
 559       m_date_gen_parser.element_strings(first,second,third,fourth,fifth,last,before,after,of);
 560     }
 561
 562     void special_values_parser(special_values_parser_type sv_parser)
 563     {
 564       m_sv_parser = sv_parser;
 565     }
 566
 567     InItrT get(InItrT& from,
 568                InItrT& to,
 569                std::ios_base& /*a_ios*/,
 570                date_type& d) const
 571     {
 572       d = m_parser.parse_date(from, to, m_format, m_sv_parser);
 573       return from;
 574     }
 575     InItrT get(InItrT& from,
 576                InItrT& to,
 577                std::ios_base& /*a_ios*/,
 578                month_type& m) const
 579     {
 580       m = m_parser.parse_month(from, to, m_month_format);
 581       return from;
 582     }
 583     InItrT get(InItrT& from,
 584                InItrT& to,
 585                std::ios_base& /*a_ios*/,
 586                day_of_week_type& wd) const
 587     {
 588       wd = m_parser.parse_weekday(from, to, m_weekday_format);
 589       return from;
 590     }
 591     //! Expects 1 or 2 digit day range: 1-31
 592     InItrT get(InItrT& from,
 593                InItrT& to,
 594                std::ios_base& /*a_ios*/,
 595                day_type& d) const
 596     {
 597       d = m_parser.parse_var_day_of_month(from, to);
 598       return from;
 599     }
 600     InItrT get(InItrT& from,
 601                InItrT& to,
 602                std::ios_base& /*a_ios*/,
 603                year_type& y) const
 604     {
 605       y = m_parser.parse_year(from, to, m_year_format);
 606       return from;
 607     }
 608     InItrT get(InItrT& from,
 609                InItrT& to,
 610                std::ios_base& a_ios,
 611                duration_type& dd) const
 612     {
 613       // skip leading whitespace
 614       while(std::isspace(*from) && from != to) { ++from; }
 615
 616       /* num_get.get() will always consume the first character if it
 617        * is a sign indicator (+/-). Special value strings may begin
 618        * with one of these signs so we'll need a copy of it
 619        * in case num_get.get() fails. */
 620       char_type c = '\0';
 621       // TODO Are these characters somewhere in the locale?
 622       if(*from == '-' || *from == '+') {
 623         c = *from;
 624       }
 625       typedef std::num_get<CharT, InItrT> num_get;
 626       typename duration_type::duration_rep_type val = 0;
 627       std::ios_base::iostate err = std::ios_base::goodbit;
 628
 629       if (std::has_facet<num_get>(a_ios.getloc())) {
 630         from = std::use_facet<num_get>(a_ios.getloc()).get(from, to, a_ios, err, val);
 631       }
 632       else {
 633         num_get* ng = new num_get();
 634         std::locale l = std::locale(a_ios.getloc(), ng);
 635         a_ios.imbue(l);
 636         from = ng->get(from, to, a_ios, err, val);
 637       }
 638       if(err & std::ios_base::failbit){
 639         typedef typename special_values_parser_type::match_results match_results;
 640         match_results mr;
 641         if(c == '-' || c == '+') { // was the first character consumed?
 642           mr.cache += c;
 643         }
 644         m_sv_parser.match(from, to, mr);
 645         if(mr.current_match == match_results::PARSE_ERROR) {
 646           boost::throw_exception(std::ios_base::failure("Parse failed. No match found for '" + mr.cache + "'"));
 647           BOOST_DATE_TIME_UNREACHABLE_EXPRESSION(return from); // should never reach
 648         }
 649         dd = duration_type(static_cast<special_values>(mr.current_match));
 650       }
 651       else {
 652         dd = duration_type(val);
 653       }
 654       return from;
 655     }
 656     InItrT get(InItrT& from,
 657                InItrT& to,
 658                std::ios_base& a_ios,
 659                period_type& p) const
 660     {
 661       p = m_period_parser.get_period(from, to, a_ios, p, duration_type::unit(), *this);
 662       return from;
 663     }
 664     InItrT get(InItrT& from,
 665                InItrT& to,
 666                std::ios_base& a_ios,
 667                nth_kday_type& nkd) const
 668     {
 669       nkd = m_date_gen_parser.get_nth_kday_type(from, to, a_ios, *this);
 670       return from;
 671     }
 672     InItrT get(InItrT& from,
 673                InItrT& to,
 674                std::ios_base& a_ios,
 675                partial_date_type& pd) const
 676     {
 677
 678       pd = m_date_gen_parser.get_partial_date_type(from, to, a_ios, *this);
 679       return from;
 680     }
 681     InItrT get(InItrT& from,
 682                InItrT& to,
 683                std::ios_base& a_ios,
 684                first_kday_type& fkd) const
 685     {
 686       fkd = m_date_gen_parser.get_first_kday_type(from, to, a_ios, *this);
 687       return from;
 688     }
 689     InItrT get(InItrT& from,
 690                InItrT& to,
 691                std::ios_base& a_ios,
 692                last_kday_type& lkd) const
 693     {
 694       lkd = m_date_gen_parser.get_last_kday_type(from, to, a_ios, *this);
 695       return from;
 696     }
 697     InItrT get(InItrT& from,
 698                InItrT& to,
 699                std::ios_base& a_ios,
 700                kday_before_type& fkb) const
 701     {
 702       fkb = m_date_gen_parser.get_kday_before_type(from, to, a_ios, *this);
 703       return from;
 704     }
 705     InItrT get(InItrT& from,
 706                InItrT& to,
 707                std::ios_base& a_ios,
 708                kday_after_type& fka) const
 709     {
 710       fka = m_date_gen_parser.get_kday_after_type(from, to, a_ios, *this);
 711       return from;
 712     }
 713
 714   protected:
 715     string_type                   m_format;
 716     string_type                   m_month_format;
 717     string_type                   m_weekday_format;
 718     string_type                   m_year_format;
 719     format_date_parser_type       m_parser;
 720     date_gen_parser_type          m_date_gen_parser;
 721     period_parser_type            m_period_parser;
 722     special_values_parser_type    m_sv_parser;
 723   private:
 724   };
 725
 726
 727   template <class date_type, class CharT, class OutItrT>
 728   std::locale::id date_input_facet<date_type, CharT, OutItrT>::id;
 729
 730   template <class date_type, class CharT, class OutItrT>
 731   const typename date_input_facet<date_type, CharT, OutItrT>::char_type
 732   date_input_facet<date_type, CharT, OutItrT>::long_weekday_format[3] = {'%','A'};
 733
 734   template <class date_type, class CharT, class OutItrT>
 735   const typename date_input_facet<date_type, CharT, OutItrT>::char_type
 736   date_input_facet<date_type, CharT, OutItrT>::short_weekday_format[3] = {'%','a'};
 737
 738   template <class date_type, class CharT, class OutItrT>
 739   const typename date_input_facet<date_type, CharT, OutItrT>::char_type
 740   date_input_facet<date_type, CharT, OutItrT>::long_month_format[3] = {'%','B'};
 741
 742   template <class date_type, class CharT, class OutItrT>
 743   const typename date_input_facet<date_type, CharT, OutItrT>::char_type
 744   date_input_facet<date_type, CharT, OutItrT>::short_month_format[3] = {'%','b'};
 745
 746   template <class date_type, class CharT, class OutItrT>
 747   const typename date_input_facet<date_type, CharT, OutItrT>::char_type
 748   date_input_facet<date_type, CharT, OutItrT>::four_digit_year_format[3] = {'%','Y'};
 749
 750   template <class date_type, class CharT, class OutItrT>
 751   const typename date_input_facet<date_type, CharT, OutItrT>::char_type
 752   date_input_facet<date_type, CharT, OutItrT>::two_digit_year_format[3] = {'%','y'};
 753
 754   template <class date_type, class CharT, class OutItrT>
 755   const typename date_input_facet<date_type, CharT, OutItrT>::char_type
 756   date_input_facet<date_type, CharT, OutItrT>::default_period_separator[4] = { ' ', '/', ' '};
 757
 758   template <class date_type, class CharT, class OutItrT>
 759   const typename date_input_facet<date_type, CharT, OutItrT>::char_type
 760   date_input_facet<date_type, CharT, OutItrT>::standard_format_specifier[3] =
 761     {'%', 'x' };
 762
 763   template <class date_type, class CharT, class OutItrT>
 764   const typename date_input_facet<date_type, CharT, OutItrT>::char_type
 765   date_input_facet<date_type, CharT, OutItrT>::iso_format_specifier[7] =
 766     {'%', 'Y', '%', 'm', '%', 'd' };
 767
 768   template <class date_type, class CharT, class OutItrT>
 769   const typename date_input_facet<date_type, CharT, OutItrT>::char_type
 770   date_input_facet<date_type, CharT, OutItrT>::iso_format_extended_specifier[9] =
 771     {'%', 'Y', '-', '%', 'm', '-', '%', 'd' };
 772
 773   template <class date_type, class CharT, class OutItrT>
 774   const typename date_input_facet<date_type, CharT, OutItrT>::char_type
 775   date_input_facet<date_type, CharT, OutItrT>::default_date_format[9] =
 776     {'%','Y','-','%','b','-','%','d'};
 777
 778 } } // namespaces
 779
 780
 781 #endif