Update concepts branch to revision 131834

[official-gcc.git] / libstdc++-v3 / include / bits / locale_facets_nonio.h

// Locale support -*- C++ -*-

// Copyright (C) 2007 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library.  This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 2, or (at your option)
// any later version.

// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License along
// with this library; see the file COPYING.  If not, write to the Free
// Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
// USA.

// As a special exception, you may use this file as part of a free software
// library without restriction.  Specifically, if other files instantiate
// templates or use macros or inline functions from this file, or you compile
// this file and link it with other files to produce an executable, this
// file does not by itself cause the resulting executable to be covered by
// the GNU General Public License.  This exception does not however
// invalidate any other reasons why the executable file might be covered by
// the GNU General Public License.

/** @file locale_facets_nonio.h
 *  This is an internal header file, included by other library headers.
 *  You should not attempt to use it directly.
 */

//
// ISO C++ 14882: 22.1  Locales
//

#ifndef _LOCALE_FACETS_NONIO_H
#define _LOCALE_FACETS_NONIO_H 1

#pragma GCC system_header

#include <ctime>        // For struct tm

_GLIBCXX_BEGIN_NAMESPACE(std)

  /**
   *  @brief  Time format ordering data.
   *
   *  This class provides an enum representing different orderings of day,
   *  month, and year.
  */
  class time_base
  {
  public:
    enum dateorder { no_order, dmy, mdy, ymd, ydm };
  };

  template<typename _CharT>
    struct __timepunct_cache : public locale::facet
    {
      // List of all known timezones, with GMT first.
      static const _CharT*              _S_timezones[14];

      const _CharT*                     _M_date_format;
      const _CharT*                     _M_date_era_format;
      const _CharT*                     _M_time_format;
      const _CharT*                     _M_time_era_format;
      const _CharT*                     _M_date_time_format;
      const _CharT*                     _M_date_time_era_format;
      const _CharT*                     _M_am;
      const _CharT*                     _M_pm;
      const _CharT*                     _M_am_pm_format;

      // Day names, starting with "C"'s Sunday.
      const _CharT*                     _M_day1;
      const _CharT*                     _M_day2;
      const _CharT*                     _M_day3;
      const _CharT*                     _M_day4;
      const _CharT*                     _M_day5;
      const _CharT*                     _M_day6;
      const _CharT*                     _M_day7;

      // Abbreviated day names, starting with "C"'s Sun.
      const _CharT*                     _M_aday1;
      const _CharT*                     _M_aday2;
      const _CharT*                     _M_aday3;
      const _CharT*                     _M_aday4;
      const _CharT*                     _M_aday5;
      const _CharT*                     _M_aday6;
      const _CharT*                     _M_aday7;

      // Month names, starting with "C"'s January.
      const _CharT*                     _M_month01;
      const _CharT*                     _M_month02;
      const _CharT*                     _M_month03;
      const _CharT*                     _M_month04;
      const _CharT*                     _M_month05;
      const _CharT*                     _M_month06;
      const _CharT*                     _M_month07;
      const _CharT*                     _M_month08;
      const _CharT*                     _M_month09;
      const _CharT*                     _M_month10;
      const _CharT*                     _M_month11;
      const _CharT*                     _M_month12;

      // Abbreviated month names, starting with "C"'s Jan.
      const _CharT*                     _M_amonth01;
      const _CharT*                     _M_amonth02;
      const _CharT*                     _M_amonth03;
      const _CharT*                     _M_amonth04;
      const _CharT*                     _M_amonth05;
      const _CharT*                     _M_amonth06;
      const _CharT*                     _M_amonth07;
      const _CharT*                     _M_amonth08;
      const _CharT*                     _M_amonth09;
      const _CharT*                     _M_amonth10;
      const _CharT*                     _M_amonth11;
      const _CharT*                     _M_amonth12;

      bool                              _M_allocated;

      __timepunct_cache(size_t __refs = 0) : facet(__refs),
      _M_date_format(NULL), _M_date_era_format(NULL), _M_time_format(NULL),
      _M_time_era_format(NULL), _M_date_time_format(NULL),
      _M_date_time_era_format(NULL), _M_am(NULL), _M_pm(NULL),
      _M_am_pm_format(NULL), _M_day1(NULL), _M_day2(NULL), _M_day3(NULL),
      _M_day4(NULL), _M_day5(NULL), _M_day6(NULL), _M_day7(NULL),
      _M_aday1(NULL), _M_aday2(NULL), _M_aday3(NULL), _M_aday4(NULL),
      _M_aday5(NULL), _M_aday6(NULL), _M_aday7(NULL), _M_month01(NULL),
      _M_month02(NULL), _M_month03(NULL), _M_month04(NULL), _M_month05(NULL),
      _M_month06(NULL), _M_month07(NULL), _M_month08(NULL), _M_month09(NULL),
      _M_month10(NULL), _M_month11(NULL), _M_month12(NULL), _M_amonth01(NULL),
      _M_amonth02(NULL), _M_amonth03(NULL), _M_amonth04(NULL),
      _M_amonth05(NULL), _M_amonth06(NULL), _M_amonth07(NULL),
      _M_amonth08(NULL), _M_amonth09(NULL), _M_amonth10(NULL),
      _M_amonth11(NULL), _M_amonth12(NULL), _M_allocated(false)
      { }

      ~__timepunct_cache();

      void
      _M_cache(const locale& __loc);

    private:
      __timepunct_cache&
      operator=(const __timepunct_cache&);
      
      explicit
      __timepunct_cache(const __timepunct_cache&);
    };

  template<typename _CharT>
    __timepunct_cache<_CharT>::~__timepunct_cache()
    {
      if (_M_allocated)
        {
          // Unused.
        }
    }

  // Specializations.
  template<>
    const char*
    __timepunct_cache<char>::_S_timezones[14];

#ifdef _GLIBCXX_USE_WCHAR_T
  template<>
    const wchar_t*
    __timepunct_cache<wchar_t>::_S_timezones[14];
#endif

  // Generic.
  template<typename _CharT>
    const _CharT* __timepunct_cache<_CharT>::_S_timezones[14];

  template<typename _CharT>
    class __timepunct : public locale::facet
    {
    public:
      // Types:
      typedef _CharT                    __char_type;
      typedef basic_string<_CharT>      __string_type;
      typedef __timepunct_cache<_CharT> __cache_type;

    protected:
      __cache_type*                     _M_data;
      __c_locale                        _M_c_locale_timepunct;
      const char*                       _M_name_timepunct;

    public:
      /// Numpunct facet id.
      static locale::id                 id;

      explicit
      __timepunct(size_t __refs = 0);

      explicit
      __timepunct(__cache_type* __cache, size_t __refs = 0);

      /**
       *  @brief  Internal constructor. Not for general use.
       *
       *  This is a constructor for use by the library itself to set up new
       *  locales.
       *
       *  @param cloc  The "C" locale.
       *  @param s  The name of a locale.
       *  @param refs  Passed to the base facet class.
      */
      explicit
      __timepunct(__c_locale __cloc, const char* __s, size_t __refs = 0);

      // FIXME: for error checking purposes _M_put should return the return
      // value of strftime/wcsftime.
      void
      _M_put(_CharT* __s, size_t __maxlen, const _CharT* __format,
             const tm* __tm) const;

      void
      _M_date_formats(const _CharT** __date) const
      {
        // Always have default first.
        __date[0] = _M_data->_M_date_format;
        __date[1] = _M_data->_M_date_era_format;
      }

      void
      _M_time_formats(const _CharT** __time) const
      {
        // Always have default first.
        __time[0] = _M_data->_M_time_format;
        __time[1] = _M_data->_M_time_era_format;
      }

      void
      _M_date_time_formats(const _CharT** __dt) const
      {
        // Always have default first.
        __dt[0] = _M_data->_M_date_time_format;
        __dt[1] = _M_data->_M_date_time_era_format;
      }

      void
      _M_am_pm_format(const _CharT* __ampm) const
      { __ampm = _M_data->_M_am_pm_format; }

      void
      _M_am_pm(const _CharT** __ampm) const
      {
        __ampm[0] = _M_data->_M_am;
        __ampm[1] = _M_data->_M_pm;
      }

      void
      _M_days(const _CharT** __days) const
      {
        __days[0] = _M_data->_M_day1;
        __days[1] = _M_data->_M_day2;
        __days[2] = _M_data->_M_day3;
        __days[3] = _M_data->_M_day4;
        __days[4] = _M_data->_M_day5;
        __days[5] = _M_data->_M_day6;
        __days[6] = _M_data->_M_day7;
      }

      void
      _M_days_abbreviated(const _CharT** __days) const
      {
        __days[0] = _M_data->_M_aday1;
        __days[1] = _M_data->_M_aday2;
        __days[2] = _M_data->_M_aday3;
        __days[3] = _M_data->_M_aday4;
        __days[4] = _M_data->_M_aday5;
        __days[5] = _M_data->_M_aday6;
        __days[6] = _M_data->_M_aday7;
      }

      void
      _M_months(const _CharT** __months) const
      {
        __months[0] = _M_data->_M_month01;
        __months[1] = _M_data->_M_month02;
        __months[2] = _M_data->_M_month03;
        __months[3] = _M_data->_M_month04;
        __months[4] = _M_data->_M_month05;
        __months[5] = _M_data->_M_month06;
        __months[6] = _M_data->_M_month07;
        __months[7] = _M_data->_M_month08;
        __months[8] = _M_data->_M_month09;
        __months[9] = _M_data->_M_month10;
        __months[10] = _M_data->_M_month11;
        __months[11] = _M_data->_M_month12;
      }

      void
      _M_months_abbreviated(const _CharT** __months) const
      {
        __months[0] = _M_data->_M_amonth01;
        __months[1] = _M_data->_M_amonth02;
        __months[2] = _M_data->_M_amonth03;
        __months[3] = _M_data->_M_amonth04;
        __months[4] = _M_data->_M_amonth05;
        __months[5] = _M_data->_M_amonth06;
        __months[6] = _M_data->_M_amonth07;
        __months[7] = _M_data->_M_amonth08;
        __months[8] = _M_data->_M_amonth09;
        __months[9] = _M_data->_M_amonth10;
        __months[10] = _M_data->_M_amonth11;
        __months[11] = _M_data->_M_amonth12;
      }

    protected:
      virtual
      ~__timepunct();

      // For use at construction time only.
      void
      _M_initialize_timepunct(__c_locale __cloc = NULL);
    };

  template<typename _CharT>
    locale::id __timepunct<_CharT>::id;

  // Specializations.
  template<>
    void
    __timepunct<char>::_M_initialize_timepunct(__c_locale __cloc);

  template<>
    void
    __timepunct<char>::_M_put(char*, size_t, const char*, const tm*) const;

#ifdef _GLIBCXX_USE_WCHAR_T
  template<>
    void
    __timepunct<wchar_t>::_M_initialize_timepunct(__c_locale __cloc);

  template<>
    void
    __timepunct<wchar_t>::_M_put(wchar_t*, size_t, const wchar_t*,
                                 const tm*) const;
#endif

_GLIBCXX_END_NAMESPACE

  // Include host and configuration specific timepunct functions.
  #include <bits/time_members.h>

_GLIBCXX_BEGIN_NAMESPACE(std)

  /**
   *  @brief  Facet for parsing dates and times.
   *
   *  This facet encapsulates the code to parse and return a date or
   *  time from a string.  It is used by the istream numeric
   *  extraction operators.
   *
   *  The time_get template uses protected virtual functions to provide the
   *  actual results.  The public accessors forward the call to the virtual
   *  functions.  These virtual functions are hooks for developers to
   *  implement the behavior they require from the time_get facet.
  */
  template<typename _CharT, typename _InIter>
    class time_get : public locale::facet, public time_base
    {
    public:
      // Types:
      //@{
      /// Public typedefs
      typedef _CharT                    char_type;
      typedef _InIter                   iter_type;
      //@}
      typedef basic_string<_CharT>      __string_type;

      /// Numpunct facet id.
      static locale::id                 id;

      /**
       *  @brief  Constructor performs initialization.
       *
       *  This is the constructor provided by the standard.
       *
       *  @param refs  Passed to the base facet class.
      */
      explicit
      time_get(size_t __refs = 0)
      : facet (__refs) { }

      /**
       *  @brief  Return preferred order of month, day, and year.
       *
       *  This function returns an enum from timebase::dateorder giving the
       *  preferred ordering if the format "x" given to time_put::put() only
       *  uses month, day, and year.  If the format "x" for the associated
       *  locale uses other fields, this function returns
       *  timebase::dateorder::noorder.
       *
       *  NOTE: The library always returns noorder at the moment.
       *
       *  @return  A member of timebase::dateorder.
      */
      dateorder
      date_order()  const
      { return this->do_date_order(); }

      /**
       *  @brief  Parse input time string.
       *
       *  This function parses a time according to the format "x" and puts the
       *  results into a user-supplied struct tm.  The result is returned by
       *  calling time_get::do_get_time().
       *
       *  If there is a valid time string according to format "x", @a tm will
       *  be filled in accordingly and the returned iterator will point to the
       *  first character beyond the time string.  If an error occurs before
       *  the end, err |= ios_base::failbit.  If parsing reads all the
       *  characters, err |= ios_base::eofbit.
       *
       *  @param  beg  Start of string to parse.
       *  @param  end  End of string to parse.
       *  @param  io  Source of the locale.
       *  @param  err  Error flags to set.
       *  @param  tm  Pointer to struct tm to fill in.
       *  @return  Iterator to first char beyond time string.
      */
      iter_type
      get_time(iter_type __beg, iter_type __end, ios_base& __io,
               ios_base::iostate& __err, tm* __tm)  const
      { return this->do_get_time(__beg, __end, __io, __err, __tm); }

      /**
       *  @brief  Parse input date string.
       *
       *  This function parses a date according to the format "X" and puts the
       *  results into a user-supplied struct tm.  The result is returned by
       *  calling time_get::do_get_date().
       *
       *  If there is a valid date string according to format "X", @a tm will
       *  be filled in accordingly and the returned iterator will point to the
       *  first character beyond the date string.  If an error occurs before
       *  the end, err |= ios_base::failbit.  If parsing reads all the
       *  characters, err |= ios_base::eofbit.
       *
       *  @param  beg  Start of string to parse.
       *  @param  end  End of string to parse.
       *  @param  io  Source of the locale.
       *  @param  err  Error flags to set.
       *  @param  tm  Pointer to struct tm to fill in.
       *  @return  Iterator to first char beyond date string.
      */
      iter_type
      get_date(iter_type __beg, iter_type __end, ios_base& __io,
               ios_base::iostate& __err, tm* __tm)  const
      { return this->do_get_date(__beg, __end, __io, __err, __tm); }

      /**
       *  @brief  Parse input weekday string.
       *
       *  This function parses a weekday name and puts the results into a
       *  user-supplied struct tm.  The result is returned by calling
       *  time_get::do_get_weekday().
       *
       *  Parsing starts by parsing an abbreviated weekday name.  If a valid
       *  abbreviation is followed by a character that would lead to the full
       *  weekday name, parsing continues until the full name is found or an
       *  error occurs.  Otherwise parsing finishes at the end of the
       *  abbreviated name.
       *
       *  If an error occurs before the end, err |= ios_base::failbit.  If
       *  parsing reads all the characters, err |= ios_base::eofbit.
       *
       *  @param  beg  Start of string to parse.
       *  @param  end  End of string to parse.
       *  @param  io  Source of the locale.
       *  @param  err  Error flags to set.
       *  @param  tm  Pointer to struct tm to fill in.
       *  @return  Iterator to first char beyond weekday name.
      */
      iter_type
      get_weekday(iter_type __beg, iter_type __end, ios_base& __io,
                  ios_base::iostate& __err, tm* __tm) const
      { return this->do_get_weekday(__beg, __end, __io, __err, __tm); }

      /**
       *  @brief  Parse input month string.
       *
       *  This function parses a month name and puts the results into a
       *  user-supplied struct tm.  The result is returned by calling
       *  time_get::do_get_monthname().
       *
       *  Parsing starts by parsing an abbreviated month name.  If a valid
       *  abbreviation is followed by a character that would lead to the full
       *  month name, parsing continues until the full name is found or an
       *  error occurs.  Otherwise parsing finishes at the end of the
       *  abbreviated name.
       *
       *  If an error occurs before the end, err |= ios_base::failbit.  If
       *  parsing reads all the characters, err |=
       *  ios_base::eofbit.
       *
       *  @param  beg  Start of string to parse.
       *  @param  end  End of string to parse.
       *  @param  io  Source of the locale.
       *  @param  err  Error flags to set.
       *  @param  tm  Pointer to struct tm to fill in.
       *  @return  Iterator to first char beyond month name.
      */
      iter_type
      get_monthname(iter_type __beg, iter_type __end, ios_base& __io,
                    ios_base::iostate& __err, tm* __tm) const
      { return this->do_get_monthname(__beg, __end, __io, __err, __tm); }

      /**
       *  @brief  Parse input year string.
       *
       *  This function reads up to 4 characters to parse a year string and
       *  puts the results into a user-supplied struct tm.  The result is
       *  returned by calling time_get::do_get_year().
       *
       *  4 consecutive digits are interpreted as a full year.  If there are
       *  exactly 2 consecutive digits, the library interprets this as the
       *  number of years since 1900.
       *
       *  If an error occurs before the end, err |= ios_base::failbit.  If
       *  parsing reads all the characters, err |= ios_base::eofbit.
       *
       *  @param  beg  Start of string to parse.
       *  @param  end  End of string to parse.
       *  @param  io  Source of the locale.
       *  @param  err  Error flags to set.
       *  @param  tm  Pointer to struct tm to fill in.
       *  @return  Iterator to first char beyond year.
      */
      iter_type
      get_year(iter_type __beg, iter_type __end, ios_base& __io,
               ios_base::iostate& __err, tm* __tm) const
      { return this->do_get_year(__beg, __end, __io, __err, __tm); }

    protected:
      /// Destructor.
      virtual
      ~time_get() { }

      /**
       *  @brief  Return preferred order of month, day, and year.
       *
       *  This function returns an enum from timebase::dateorder giving the
       *  preferred ordering if the format "x" given to time_put::put() only
       *  uses month, day, and year.  This function is a hook for derived
       *  classes to change the value returned.
       *
       *  @return  A member of timebase::dateorder.
      */
      virtual dateorder
      do_date_order() const;

      /**
       *  @brief  Parse input time string.
       *
       *  This function parses a time according to the format "x" and puts the
       *  results into a user-supplied struct tm.  This function is a hook for
       *  derived classes to change the value returned.  @see get_time() for
       *  details.
       *
       *  @param  beg  Start of string to parse.
       *  @param  end  End of string to parse.
       *  @param  io  Source of the locale.
       *  @param  err  Error flags to set.
       *  @param  tm  Pointer to struct tm to fill in.
       *  @return  Iterator to first char beyond time string.
      */
      virtual iter_type
      do_get_time(iter_type __beg, iter_type __end, ios_base& __io,
                  ios_base::iostate& __err, tm* __tm) const;

      /**
       *  @brief  Parse input date string.
       *
       *  This function parses a date according to the format "X" and puts the
       *  results into a user-supplied struct tm.  This function is a hook for
       *  derived classes to change the value returned.  @see get_date() for
       *  details.
       *
       *  @param  beg  Start of string to parse.
       *  @param  end  End of string to parse.
       *  @param  io  Source of the locale.
       *  @param  err  Error flags to set.
       *  @param  tm  Pointer to struct tm to fill in.
       *  @return  Iterator to first char beyond date string.
      */
      virtual iter_type
      do_get_date(iter_type __beg, iter_type __end, ios_base& __io,
                  ios_base::iostate& __err, tm* __tm) const;

      /**
       *  @brief  Parse input weekday string.
       *
       *  This function parses a weekday name and puts the results into a
       *  user-supplied struct tm.  This function is a hook for derived
       *  classes to change the value returned.  @see get_weekday() for
       *  details.
       *
       *  @param  beg  Start of string to parse.
       *  @param  end  End of string to parse.
       *  @param  io  Source of the locale.
       *  @param  err  Error flags to set.
       *  @param  tm  Pointer to struct tm to fill in.
       *  @return  Iterator to first char beyond weekday name.
      */
      virtual iter_type
      do_get_weekday(iter_type __beg, iter_type __end, ios_base&,
                     ios_base::iostate& __err, tm* __tm) const;

      /**
       *  @brief  Parse input month string.
       *
       *  This function parses a month name and puts the results into a
       *  user-supplied struct tm.  This function is a hook for derived
       *  classes to change the value returned.  @see get_monthname() for
       *  details.
       *
       *  @param  beg  Start of string to parse.
       *  @param  end  End of string to parse.
       *  @param  io  Source of the locale.
       *  @param  err  Error flags to set.
       *  @param  tm  Pointer to struct tm to fill in.
       *  @return  Iterator to first char beyond month name.
      */
      virtual iter_type
      do_get_monthname(iter_type __beg, iter_type __end, ios_base&,
                       ios_base::iostate& __err, tm* __tm) const;

      /**
       *  @brief  Parse input year string.
       *
       *  This function reads up to 4 characters to parse a year string and
       *  puts the results into a user-supplied struct tm.  This function is a
       *  hook for derived classes to change the value returned.  @see
       *  get_year() for details.
       *
       *  @param  beg  Start of string to parse.
       *  @param  end  End of string to parse.
       *  @param  io  Source of the locale.
       *  @param  err  Error flags to set.
       *  @param  tm  Pointer to struct tm to fill in.
       *  @return  Iterator to first char beyond year.
      */
      virtual iter_type
      do_get_year(iter_type __beg, iter_type __end, ios_base& __io,
                  ios_base::iostate& __err, tm* __tm) const;

      // Extract numeric component of length __len.
      iter_type
      _M_extract_num(iter_type __beg, iter_type __end, int& __member,
                     int __min, int __max, size_t __len,
                     ios_base& __io, ios_base::iostate& __err) const;

      // Extract day or month name, or any unique array of string
      // literals in a const _CharT* array.
      iter_type
      _M_extract_name(iter_type __beg, iter_type __end, int& __member,
                      const _CharT** __names, size_t __indexlen,
                      ios_base& __io, ios_base::iostate& __err) const;

      // Extract on a component-by-component basis, via __format argument.
      iter_type
      _M_extract_via_format(iter_type __beg, iter_type __end, ios_base& __io,
                            ios_base::iostate& __err, tm* __tm,
                            const _CharT* __format) const;
    };

  template<typename _CharT, typename _InIter>
    locale::id time_get<_CharT, _InIter>::id;

  /// class time_get_byname [22.2.5.2].
  template<typename _CharT, typename _InIter>
    class time_get_byname : public time_get<_CharT, _InIter>
    {
    public:
      // Types:
      typedef _CharT                    char_type;
      typedef _InIter                   iter_type;

      explicit
      time_get_byname(const char*, size_t __refs = 0)
      : time_get<_CharT, _InIter>(__refs) { }

    protected:
      virtual
      ~time_get_byname() { }
    };

  /**
   *  @brief  Facet for outputting dates and times.
   *
   *  This facet encapsulates the code to format and output dates and times
   *  according to formats used by strftime().
   *
   *  The time_put template uses protected virtual functions to provide the
   *  actual results.  The public accessors forward the call to the virtual
   *  functions.  These virtual functions are hooks for developers to
   *  implement the behavior they require from the time_put facet.
  */
  template<typename _CharT, typename _OutIter>
    class time_put : public locale::facet
    {
    public:
      // Types:
      //@{
      /// Public typedefs
      typedef _CharT                    char_type;
      typedef _OutIter                  iter_type;
      //@}

      /// Numpunct facet id.
      static locale::id                 id;

      /**
       *  @brief  Constructor performs initialization.
       *
       *  This is the constructor provided by the standard.
       *
       *  @param refs  Passed to the base facet class.
      */
      explicit
      time_put(size_t __refs = 0)
      : facet(__refs) { }

      /**
       *  @brief  Format and output a time or date.
       *
       *  This function formats the data in struct tm according to the
       *  provided format string.  The format string is interpreted as by
       *  strftime().
       *
       *  @param  s  The stream to write to.
       *  @param  io  Source of locale.
       *  @param  fill  char_type to use for padding.
       *  @param  tm  Struct tm with date and time info to format.
       *  @param  beg  Start of format string.
       *  @param  end  End of format string.
       *  @return  Iterator after writing.
       */
      iter_type
      put(iter_type __s, ios_base& __io, char_type __fill, const tm* __tm,
          const _CharT* __beg, const _CharT* __end) const;

      /**
       *  @brief  Format and output a time or date.
       *
       *  This function formats the data in struct tm according to the
       *  provided format char and optional modifier.  The format and modifier
       *  are interpreted as by strftime().  It does so by returning
       *  time_put::do_put().
       *
       *  @param  s  The stream to write to.
       *  @param  io  Source of locale.
       *  @param  fill  char_type to use for padding.
       *  @param  tm  Struct tm with date and time info to format.
       *  @param  format  Format char.
       *  @param  mod  Optional modifier char.
       *  @return  Iterator after writing.
       */
      iter_type
      put(iter_type __s, ios_base& __io, char_type __fill,
          const tm* __tm, char __format, char __mod = 0) const
      { return this->do_put(__s, __io, __fill, __tm, __format, __mod); }

    protected:
      /// Destructor.
      virtual
      ~time_put()
      { }

      /**
       *  @brief  Format and output a time or date.
       *
       *  This function formats the data in struct tm according to the
       *  provided format char and optional modifier.  This function is a hook
       *  for derived classes to change the value returned.  @see put() for
       *  more details.
       *
       *  @param  s  The stream to write to.
       *  @param  io  Source of locale.
       *  @param  fill  char_type to use for padding.
       *  @param  tm  Struct tm with date and time info to format.
       *  @param  format  Format char.
       *  @param  mod  Optional modifier char.
       *  @return  Iterator after writing.
       */
      virtual iter_type
      do_put(iter_type __s, ios_base& __io, char_type __fill, const tm* __tm,
             char __format, char __mod) const;
    };

  template<typename _CharT, typename _OutIter>
    locale::id time_put<_CharT, _OutIter>::id;

  /// class time_put_byname [22.2.5.4].
  template<typename _CharT, typename _OutIter>
    class time_put_byname : public time_put<_CharT, _OutIter>
    {
    public:
      // Types:
      typedef _CharT                    char_type;
      typedef _OutIter                  iter_type;

      explicit
      time_put_byname(const char*, size_t __refs = 0)
      : time_put<_CharT, _OutIter>(__refs)
      { };

    protected:
      virtual
      ~time_put_byname() { }
    };


  /**
   *  @brief  Money format ordering data.
   *
   *  This class contains an ordered array of 4 fields to represent the
   *  pattern for formatting a money amount.  Each field may contain one entry
   *  from the part enum.  symbol, sign, and value must be present and the
   *  remaining field must contain either none or space.  @see
   *  moneypunct::pos_format() and moneypunct::neg_format() for details of how
   *  these fields are interpreted.
  */
  class money_base
  {
  public:
    enum part { none, space, symbol, sign, value };
    struct pattern { char field[4]; };

    static const pattern _S_default_pattern;

    enum
    {
      _S_minus,
      _S_zero,
      _S_end = 11
    };

    // String literal of acceptable (narrow) input/output, for
    // money_get/money_put. "-0123456789"
    static const char* _S_atoms;

    // Construct and return valid pattern consisting of some combination of:
    // space none symbol sign value
    static pattern
    _S_construct_pattern(char __precedes, char __space, char __posn);
  };

  template<typename _CharT, bool _Intl>
    struct __moneypunct_cache : public locale::facet
    {
      const char*                       _M_grouping;
      size_t                            _M_grouping_size;
      bool                              _M_use_grouping;
      _CharT                            _M_decimal_point;
      _CharT                            _M_thousands_sep;
      const _CharT*                     _M_curr_symbol;
      size_t                            _M_curr_symbol_size;
      const _CharT*                     _M_positive_sign;
      size_t                            _M_positive_sign_size;
      const _CharT*                     _M_negative_sign;
      size_t                            _M_negative_sign_size;
      int                               _M_frac_digits;
      money_base::pattern               _M_pos_format;
      money_base::pattern               _M_neg_format;

      // A list of valid numeric literals for input and output: in the standard
      // "C" locale, this is "-0123456789". This array contains the chars after
      // having been passed through the current locale's ctype<_CharT>.widen().
      _CharT                            _M_atoms[money_base::_S_end];

      bool                              _M_allocated;

      __moneypunct_cache(size_t __refs = 0) : facet(__refs),
      _M_grouping(NULL), _M_grouping_size(0), _M_use_grouping(false),
      _M_decimal_point(_CharT()), _M_thousands_sep(_CharT()),
      _M_curr_symbol(NULL), _M_curr_symbol_size(0),
      _M_positive_sign(NULL), _M_positive_sign_size(0),
      _M_negative_sign(NULL), _M_negative_sign_size(0),
      _M_frac_digits(0),
      _M_pos_format(money_base::pattern()),
      _M_neg_format(money_base::pattern()), _M_allocated(false)
      { }

      ~__moneypunct_cache();

      void
      _M_cache(const locale& __loc);

    private:
      __moneypunct_cache&
      operator=(const __moneypunct_cache&);
      
      explicit
      __moneypunct_cache(const __moneypunct_cache&);
    };

  template<typename _CharT, bool _Intl>
    __moneypunct_cache<_CharT, _Intl>::~__moneypunct_cache()
    {
      if (_M_allocated)
        {
          delete [] _M_grouping;
          delete [] _M_curr_symbol;
          delete [] _M_positive_sign;
          delete [] _M_negative_sign;
        }
    }

  /**
   *  @brief  Facet for formatting data for money amounts.
   *
   *  This facet encapsulates the punctuation, grouping and other formatting
   *  features of money amount string representations.
  */
  template<typename _CharT, bool _Intl>
    class moneypunct : public locale::facet, public money_base
    {
    public:
      // Types:
      //@{
      /// Public typedefs
      typedef _CharT                    char_type;
      typedef basic_string<_CharT>      string_type;
      //@}
      typedef __moneypunct_cache<_CharT, _Intl>     __cache_type;

    private:
      __cache_type*                     _M_data;

    public:
      /// This value is provided by the standard, but no reason for its
      /// existence.
      static const bool                 intl = _Intl;
      /// Numpunct facet id.
      static locale::id                 id;

      /**
       *  @brief  Constructor performs initialization.
       *
       *  This is the constructor provided by the standard.
       *
       *  @param refs  Passed to the base facet class.
      */
      explicit
      moneypunct(size_t __refs = 0) : facet(__refs), _M_data(NULL)
      { _M_initialize_moneypunct(); }

      /**
       *  @brief  Constructor performs initialization.
       *
       *  This is an internal constructor.
       *
       *  @param cache  Cache for optimization.
       *  @param refs  Passed to the base facet class.
      */
      explicit
      moneypunct(__cache_type* __cache, size_t __refs = 0)
      : facet(__refs), _M_data(__cache)
      { _M_initialize_moneypunct(); }

      /**
       *  @brief  Internal constructor. Not for general use.
       *
       *  This is a constructor for use by the library itself to set up new
       *  locales.
       *
       *  @param cloc  The "C" locale.
       *  @param s  The name of a locale.
       *  @param refs  Passed to the base facet class.
      */
      explicit
      moneypunct(__c_locale __cloc, const char* __s, size_t __refs = 0)
      : facet(__refs), _M_data(NULL)
      { _M_initialize_moneypunct(__cloc, __s); }

      /**
       *  @brief  Return decimal point character.
       *
       *  This function returns a char_type to use as a decimal point.  It
       *  does so by returning returning
       *  moneypunct<char_type>::do_decimal_point().
       *
       *  @return  @a char_type representing a decimal point.
      */
      char_type
      decimal_point() const
      { return this->do_decimal_point(); }

      /**
       *  @brief  Return thousands separator character.
       *
       *  This function returns a char_type to use as a thousands
       *  separator.  It does so by returning returning
       *  moneypunct<char_type>::do_thousands_sep().
       *
       *  @return  char_type representing a thousands separator.
      */
      char_type
      thousands_sep() const
      { return this->do_thousands_sep(); }

      /**
       *  @brief  Return grouping specification.
       *
       *  This function returns a string representing groupings for the
       *  integer part of an amount.  Groupings indicate where thousands
       *  separators should be inserted.
       *
       *  Each char in the return string is interpret as an integer rather
       *  than a character.  These numbers represent the number of digits in a
       *  group.  The first char in the string represents the number of digits
       *  in the least significant group.  If a char is negative, it indicates
       *  an unlimited number of digits for the group.  If more chars from the
       *  string are required to group a number, the last char is used
       *  repeatedly.
       *
       *  For example, if the grouping() returns "\003\002" and is applied to
       *  the number 123456789, this corresponds to 12,34,56,789.  Note that
       *  if the string was "32", this would put more than 50 digits into the
       *  least significant group if the character set is ASCII.
       *
       *  The string is returned by calling
       *  moneypunct<char_type>::do_grouping().
       *
       *  @return  string representing grouping specification.
      */
      string
      grouping() const
      { return this->do_grouping(); }

      /**
       *  @brief  Return currency symbol string.
       *
       *  This function returns a string_type to use as a currency symbol.  It
       *  does so by returning returning
       *  moneypunct<char_type>::do_curr_symbol().
       *
       *  @return  @a string_type representing a currency symbol.
      */
      string_type
      curr_symbol() const
      { return this->do_curr_symbol(); }

      /**
       *  @brief  Return positive sign string.
       *
       *  This function returns a string_type to use as a sign for positive
       *  amounts.  It does so by returning returning
       *  moneypunct<char_type>::do_positive_sign().
       *
       *  If the return value contains more than one character, the first
       *  character appears in the position indicated by pos_format() and the
       *  remainder appear at the end of the formatted string.
       *
       *  @return  @a string_type representing a positive sign.
      */
      string_type
      positive_sign() const
      { return this->do_positive_sign(); }

      /**
       *  @brief  Return negative sign string.
       *
       *  This function returns a string_type to use as a sign for negative
       *  amounts.  It does so by returning returning
       *  moneypunct<char_type>::do_negative_sign().
       *
       *  If the return value contains more than one character, the first
       *  character appears in the position indicated by neg_format() and the
       *  remainder appear at the end of the formatted string.
       *
       *  @return  @a string_type representing a negative sign.
      */
      string_type
      negative_sign() const
      { return this->do_negative_sign(); }

      /**
       *  @brief  Return number of digits in fraction.
       *
       *  This function returns the exact number of digits that make up the
       *  fractional part of a money amount.  It does so by returning
       *  returning moneypunct<char_type>::do_frac_digits().
       *
       *  The fractional part of a money amount is optional.  But if it is
       *  present, there must be frac_digits() digits.
       *
       *  @return  Number of digits in amount fraction.
      */
      int
      frac_digits() const
      { return this->do_frac_digits(); }

      //@{
      /**
       *  @brief  Return pattern for money values.
       *
       *  This function returns a pattern describing the formatting of a
       *  positive or negative valued money amount.  It does so by returning
       *  returning moneypunct<char_type>::do_pos_format() or
       *  moneypunct<char_type>::do_neg_format().
       *
       *  The pattern has 4 fields describing the ordering of symbol, sign,
       *  value, and none or space.  There must be one of each in the pattern.
       *  The none and space enums may not appear in the first field and space
       *  may not appear in the final field.
       *
       *  The parts of a money string must appear in the order indicated by
       *  the fields of the pattern.  The symbol field indicates that the
       *  value of curr_symbol() may be present.  The sign field indicates
       *  that the value of positive_sign() or negative_sign() must be
       *  present.  The value field indicates that the absolute value of the
       *  money amount is present.  none indicates 0 or more whitespace
       *  characters, except at the end, where it permits no whitespace.
       *  space indicates that 1 or more whitespace characters must be
       *  present.
       *
       *  For example, for the US locale and pos_format() pattern
       *  {symbol,sign,value,none}, curr_symbol() == '$' positive_sign() ==
       *  '+', and value 10.01, and options set to force the symbol, the
       *  corresponding string is "$+10.01".
       *
       *  @return  Pattern for money values.
      */
      pattern
      pos_format() const
      { return this->do_pos_format(); }

      pattern
      neg_format() const
      { return this->do_neg_format(); }
      //@}

    protected:
      /// Destructor.
      virtual
      ~moneypunct();

      /**
       *  @brief  Return decimal point character.
       *
       *  Returns a char_type to use as a decimal point.  This function is a
       *  hook for derived classes to change the value returned.
       *
       *  @return  @a char_type representing a decimal point.
      */
      virtual char_type
      do_decimal_point() const
      { return _M_data->_M_decimal_point; }

      /**
       *  @brief  Return thousands separator character.
       *
       *  Returns a char_type to use as a thousands separator.  This function
       *  is a hook for derived classes to change the value returned.
       *
       *  @return  @a char_type representing a thousands separator.
      */
      virtual char_type
      do_thousands_sep() const
      { return _M_data->_M_thousands_sep; }

      /**
       *  @brief  Return grouping specification.
       *
       *  Returns a string representing groupings for the integer part of a
       *  number.  This function is a hook for derived classes to change the
       *  value returned.  @see grouping() for details.
       *
       *  @return  String representing grouping specification.
      */
      virtual string
      do_grouping() const
      { return _M_data->_M_grouping; }

      /**
       *  @brief  Return currency symbol string.
       *
       *  This function returns a string_type to use as a currency symbol.
       *  This function is a hook for derived classes to change the value
       *  returned.  @see curr_symbol() for details.
       *
       *  @return  @a string_type representing a currency symbol.
      */
      virtual string_type
      do_curr_symbol()   const
      { return _M_data->_M_curr_symbol; }

      /**
       *  @brief  Return positive sign string.
       *
       *  This function returns a string_type to use as a sign for positive
       *  amounts.  This function is a hook for derived classes to change the
       *  value returned.  @see positive_sign() for details.
       *
       *  @return  @a string_type representing a positive sign.
      */
      virtual string_type
      do_positive_sign() const
      { return _M_data->_M_positive_sign; }

      /**
       *  @brief  Return negative sign string.
       *
       *  This function returns a string_type to use as a sign for negative
       *  amounts.  This function is a hook for derived classes to change the
       *  value returned.  @see negative_sign() for details.
       *
       *  @return  @a string_type representing a negative sign.
      */
      virtual string_type
      do_negative_sign() const
      { return _M_data->_M_negative_sign; }

      /**
       *  @brief  Return number of digits in fraction.
       *
       *  This function returns the exact number of digits that make up the
       *  fractional part of a money amount.  This function is a hook for
       *  derived classes to change the value returned.  @see frac_digits()
       *  for details.
       *
       *  @return  Number of digits in amount fraction.
      */
      virtual int
      do_frac_digits() const
      { return _M_data->_M_frac_digits; }

      /**
       *  @brief  Return pattern for money values.
       *
       *  This function returns a pattern describing the formatting of a
       *  positive valued money amount.  This function is a hook for derived
       *  classes to change the value returned.  @see pos_format() for
       *  details.
       *
       *  @return  Pattern for money values.
      */
      virtual pattern
      do_pos_format() const
      { return _M_data->_M_pos_format; }

      /**
       *  @brief  Return pattern for money values.
       *
       *  This function returns a pattern describing the formatting of a
       *  negative valued money amount.  This function is a hook for derived
       *  classes to change the value returned.  @see neg_format() for
       *  details.
       *
       *  @return  Pattern for money values.
      */
      virtual pattern
      do_neg_format() const
      { return _M_data->_M_neg_format; }

      // For use at construction time only.
       void
       _M_initialize_moneypunct(__c_locale __cloc = NULL,
                                const char* __name = NULL);
    };

  template<typename _CharT, bool _Intl>
    locale::id moneypunct<_CharT, _Intl>::id;

  template<typename _CharT, bool _Intl>
    const bool moneypunct<_CharT, _Intl>::intl;

  template<>
    moneypunct<char, true>::~moneypunct();

  template<>
    moneypunct<char, false>::~moneypunct();

  template<>
    void
    moneypunct<char, true>::_M_initialize_moneypunct(__c_locale, const char*);

  template<>
    void
    moneypunct<char, false>::_M_initialize_moneypunct(__c_locale, const char*);

#ifdef _GLIBCXX_USE_WCHAR_T
  template<>
    moneypunct<wchar_t, true>::~moneypunct();

  template<>
    moneypunct<wchar_t, false>::~moneypunct();

  template<>
    void
    moneypunct<wchar_t, true>::_M_initialize_moneypunct(__c_locale,
                                                        const char*);

  template<>
    void
    moneypunct<wchar_t, false>::_M_initialize_moneypunct(__c_locale,
                                                         const char*);
#endif

  /// class moneypunct_byname [22.2.6.4].
  template<typename _CharT, bool _Intl>
    class moneypunct_byname : public moneypunct<_CharT, _Intl>
    {
    public:
      typedef _CharT                    char_type;
      typedef basic_string<_CharT>      string_type;

      static const bool intl = _Intl;

      explicit
      moneypunct_byname(const char* __s, size_t __refs = 0)
      : moneypunct<_CharT, _Intl>(__refs)
      {
        if (__builtin_strcmp(__s, "C") != 0
            && __builtin_strcmp(__s, "POSIX") != 0)
          {
            __c_locale __tmp;
            this->_S_create_c_locale(__tmp, __s);
            this->_M_initialize_moneypunct(__tmp);
            this->_S_destroy_c_locale(__tmp);
          }
      }

    protected:
      virtual
      ~moneypunct_byname() { }
    };

  template<typename _CharT, bool _Intl>
    const bool moneypunct_byname<_CharT, _Intl>::intl;

_GLIBCXX_BEGIN_LDBL_NAMESPACE

  /**
   *  @brief  Facet for parsing monetary amounts.
   *
   *  This facet encapsulates the code to parse and return a monetary
   *  amount from a string.
   *
   *  The money_get template uses protected virtual functions to
   *  provide the actual results.  The public accessors forward the
   *  call to the virtual functions.  These virtual functions are
   *  hooks for developers to implement the behavior they require from
   *  the money_get facet.
  */
  template<typename _CharT, typename _InIter>
    class money_get : public locale::facet
    {
    public:
      // Types:
      //@{
      /// Public typedefs
      typedef _CharT                    char_type;
      typedef _InIter                   iter_type;
      typedef basic_string<_CharT>      string_type;
      //@}

      /// Numpunct facet id.
      static locale::id                 id;

      /**
       *  @brief  Constructor performs initialization.
       *
       *  This is the constructor provided by the standard.
       *
       *  @param refs  Passed to the base facet class.
      */
      explicit
      money_get(size_t __refs = 0) : facet(__refs) { }

      /**
       *  @brief  Read and parse a monetary value.
       *
       *  This function reads characters from @a s, interprets them as a
       *  monetary value according to moneypunct and ctype facets retrieved
       *  from io.getloc(), and returns the result in @a units as an integral
       *  value moneypunct::frac_digits() * the actual amount.  For example,
       *  the string $10.01 in a US locale would store 1001 in @a units.
       *
       *  Any characters not part of a valid money amount are not consumed.
       *
       *  If a money value cannot be parsed from the input stream, sets
       *  err=(err|io.failbit).  If the stream is consumed before finishing
       *  parsing,  sets err=(err|io.failbit|io.eofbit).  @a units is
       *  unchanged if parsing fails.
       *
       *  This function works by returning the result of do_get().
       *
       *  @param  s  Start of characters to parse.
       *  @param  end  End of characters to parse.
       *  @param  intl  Parameter to use_facet<moneypunct<CharT,intl> >.
       *  @param  io  Source of facets and io state.
       *  @param  err  Error field to set if parsing fails.
       *  @param  units  Place to store result of parsing.
       *  @return  Iterator referencing first character beyond valid money
       *           amount.
       */
      iter_type
      get(iter_type __s, iter_type __end, bool __intl, ios_base& __io,
          ios_base::iostate& __err, long double& __units) const
      { return this->do_get(__s, __end, __intl, __io, __err, __units); }

      /**
       *  @brief  Read and parse a monetary value.
       *
       *  This function reads characters from @a s, interprets them as a
       *  monetary value according to moneypunct and ctype facets retrieved
       *  from io.getloc(), and returns the result in @a digits.  For example,
       *  the string $10.01 in a US locale would store "1001" in @a digits.
       *
       *  Any characters not part of a valid money amount are not consumed.
       *
       *  If a money value cannot be parsed from the input stream, sets
       *  err=(err|io.failbit).  If the stream is consumed before finishing
       *  parsing,  sets err=(err|io.failbit|io.eofbit).
       *
       *  This function works by returning the result of do_get().
       *
       *  @param  s  Start of characters to parse.
       *  @param  end  End of characters to parse.
       *  @param  intl  Parameter to use_facet<moneypunct<CharT,intl> >.
       *  @param  io  Source of facets and io state.
       *  @param  err  Error field to set if parsing fails.
       *  @param  digits  Place to store result of parsing.
       *  @return  Iterator referencing first character beyond valid money
       *           amount.
       */
      iter_type
      get(iter_type __s, iter_type __end, bool __intl, ios_base& __io,
          ios_base::iostate& __err, string_type& __digits) const
      { return this->do_get(__s, __end, __intl, __io, __err, __digits); }

    protected:
      /// Destructor.
      virtual
      ~money_get() { }

      /**
       *  @brief  Read and parse a monetary value.
       *
       *  This function reads and parses characters representing a monetary
       *  value.  This function is a hook for derived classes to change the
       *  value returned.  @see get() for details.
       */
      // XXX GLIBCXX_ABI Deprecated
#if defined _GLIBCXX_LONG_DOUBLE_COMPAT && defined __LONG_DOUBLE_128__
      virtual iter_type
      __do_get(iter_type __s, iter_type __end, bool __intl, ios_base& __io,
               ios_base::iostate& __err, double& __units) const;
#else
      virtual iter_type
      do_get(iter_type __s, iter_type __end, bool __intl, ios_base& __io,
             ios_base::iostate& __err, long double& __units) const;
#endif

      /**
       *  @brief  Read and parse a monetary value.
       *
       *  This function reads and parses characters representing a monetary
       *  value.  This function is a hook for derived classes to change the
       *  value returned.  @see get() for details.
       */
      virtual iter_type
      do_get(iter_type __s, iter_type __end, bool __intl, ios_base& __io,
             ios_base::iostate& __err, string_type& __digits) const;

      // XXX GLIBCXX_ABI Deprecated
#if defined _GLIBCXX_LONG_DOUBLE_COMPAT && defined __LONG_DOUBLE_128__
      virtual iter_type
      do_get(iter_type __s, iter_type __end, bool __intl, ios_base& __io,
             ios_base::iostate& __err, long double& __units) const;
#endif

      template<bool _Intl>
        iter_type
        _M_extract(iter_type __s, iter_type __end, ios_base& __io,
                   ios_base::iostate& __err, string& __digits) const;     
    };

  template<typename _CharT, typename _InIter>
    locale::id money_get<_CharT, _InIter>::id;

  /**
   *  @brief  Facet for outputting monetary amounts.
   *
   *  This facet encapsulates the code to format and output a monetary
   *  amount.
   *
   *  The money_put template uses protected virtual functions to
   *  provide the actual results.  The public accessors forward the
   *  call to the virtual functions.  These virtual functions are
   *  hooks for developers to implement the behavior they require from
   *  the money_put facet.
  */
  template<typename _CharT, typename _OutIter>
    class money_put : public locale::facet
    {
    public:
      //@{
      /// Public typedefs
      typedef _CharT                    char_type;
      typedef _OutIter                  iter_type;
      typedef basic_string<_CharT>      string_type;
      //@}

      /// Numpunct facet id.
      static locale::id                 id;

      /**
       *  @brief  Constructor performs initialization.
       *
       *  This is the constructor provided by the standard.
       *
       *  @param refs  Passed to the base facet class.
      */
      explicit
      money_put(size_t __refs = 0) : facet(__refs) { }

      /**
       *  @brief  Format and output a monetary value.
       *
       *  This function formats @a units as a monetary value according to
       *  moneypunct and ctype facets retrieved from io.getloc(), and writes
       *  the resulting characters to @a s.  For example, the value 1001 in a
       *  US locale would write "$10.01" to @a s.
       *
       *  This function works by returning the result of do_put().
       *
       *  @param  s  The stream to write to.
       *  @param  intl  Parameter to use_facet<moneypunct<CharT,intl> >.
       *  @param  io  Source of facets and io state.
       *  @param  fill  char_type to use for padding.
       *  @param  units  Place to store result of parsing.
       *  @return  Iterator after writing.
       */
      iter_type
      put(iter_type __s, bool __intl, ios_base& __io,
          char_type __fill, long double __units) const
      { return this->do_put(__s, __intl, __io, __fill, __units); }

      /**
       *  @brief  Format and output a monetary value.
       *
       *  This function formats @a digits as a monetary value according to
       *  moneypunct and ctype facets retrieved from io.getloc(), and writes
       *  the resulting characters to @a s.  For example, the string "1001" in
       *  a US locale would write "$10.01" to @a s.
       *
       *  This function works by returning the result of do_put().
       *
       *  @param  s  The stream to write to.
       *  @param  intl  Parameter to use_facet<moneypunct<CharT,intl> >.
       *  @param  io  Source of facets and io state.
       *  @param  fill  char_type to use for padding.
       *  @param  units  Place to store result of parsing.
       *  @return  Iterator after writing.
       */
      iter_type
      put(iter_type __s, bool __intl, ios_base& __io,
          char_type __fill, const string_type& __digits) const
      { return this->do_put(__s, __intl, __io, __fill, __digits); }

    protected:
      /// Destructor.
      virtual
      ~money_put() { }

      /**
       *  @brief  Format and output a monetary value.
       *
       *  This function formats @a units as a monetary value according to
       *  moneypunct and ctype facets retrieved from io.getloc(), and writes
       *  the resulting characters to @a s.  For example, the value 1001 in a
       *  US locale would write "$10.01" to @a s.
       *
       *  This function is a hook for derived classes to change the value
       *  returned.  @see put().
       *
       *  @param  s  The stream to write to.
       *  @param  intl  Parameter to use_facet<moneypunct<CharT,intl> >.
       *  @param  io  Source of facets and io state.
       *  @param  fill  char_type to use for padding.
       *  @param  units  Place to store result of parsing.
       *  @return  Iterator after writing.
       */
      // XXX GLIBCXX_ABI Deprecated
#if defined _GLIBCXX_LONG_DOUBLE_COMPAT && defined __LONG_DOUBLE_128__
      virtual iter_type
      __do_put(iter_type __s, bool __intl, ios_base& __io, char_type __fill,
               double __units) const;
#else
      virtual iter_type
      do_put(iter_type __s, bool __intl, ios_base& __io, char_type __fill,
             long double __units) const;
#endif

      /**
       *  @brief  Format and output a monetary value.
       *
       *  This function formats @a digits as a monetary value according to
       *  moneypunct and ctype facets retrieved from io.getloc(), and writes
       *  the resulting characters to @a s.  For example, the string "1001" in
       *  a US locale would write "$10.01" to @a s.
       *
       *  This function is a hook for derived classes to change the value
       *  returned.  @see put().
       *
       *  @param  s  The stream to write to.
       *  @param  intl  Parameter to use_facet<moneypunct<CharT,intl> >.
       *  @param  io  Source of facets and io state.
       *  @param  fill  char_type to use for padding.
       *  @param  units  Place to store result of parsing.
       *  @return  Iterator after writing.
       */
      virtual iter_type
      do_put(iter_type __s, bool __intl, ios_base& __io, char_type __fill,
             const string_type& __digits) const;

      // XXX GLIBCXX_ABI Deprecated
#if defined _GLIBCXX_LONG_DOUBLE_COMPAT && defined __LONG_DOUBLE_128__
      virtual iter_type
      do_put(iter_type __s, bool __intl, ios_base& __io, char_type __fill,
             long double __units) const;
#endif

      template<bool _Intl>
        iter_type
        _M_insert(iter_type __s, ios_base& __io, char_type __fill,
                  const string_type& __digits) const;
    };

  template<typename _CharT, typename _OutIter>
    locale::id money_put<_CharT, _OutIter>::id;

_GLIBCXX_END_LDBL_NAMESPACE

  /**
   *  @brief  Messages facet base class providing catalog typedef.
   */
  struct messages_base
  {
    typedef int catalog;
  };

  /**
   *  @brief  Facet for handling message catalogs
   *
   *  This facet encapsulates the code to retrieve messages from
   *  message catalogs.  The only thing defined by the standard for this facet
   *  is the interface.  All underlying functionality is
   *  implementation-defined.
   *
   *  This library currently implements 3 versions of the message facet.  The
   *  first version (gnu) is a wrapper around gettext, provided by libintl.
   *  The second version (ieee) is a wrapper around catgets.  The final
   *  version (default) does no actual translation.  These implementations are
   *  only provided for char and wchar_t instantiations.
   *
   *  The messages template uses protected virtual functions to
   *  provide the actual results.  The public accessors forward the
   *  call to the virtual functions.  These virtual functions are
   *  hooks for developers to implement the behavior they require from
   *  the messages facet.
  */
  template<typename _CharT>
    class messages : public locale::facet, public messages_base
    {
    public:
      // Types:
      //@{
      /// Public typedefs
      typedef _CharT                    char_type;
      typedef basic_string<_CharT>      string_type;
      //@}

    protected:
      // Underlying "C" library locale information saved from
      // initialization, needed by messages_byname as well.
      __c_locale                        _M_c_locale_messages;
      const char*                       _M_name_messages;

    public:
      /// Numpunct facet id.
      static locale::id                 id;

      /**
       *  @brief  Constructor performs initialization.
       *
       *  This is the constructor provided by the standard.
       *
       *  @param refs  Passed to the base facet class.
      */
      explicit
      messages(size_t __refs = 0);

      // Non-standard.
      /**
       *  @brief  Internal constructor.  Not for general use.
       *
       *  This is a constructor for use by the library itself to set up new
       *  locales.
       *
       *  @param  cloc  The "C" locale.
       *  @param  s  The name of a locale.
       *  @param  refs  Refcount to pass to the base class.
       */
      explicit
      messages(__c_locale __cloc, const char* __s, size_t __refs = 0);

      /*
       *  @brief  Open a message catalog.
       *
       *  This function opens and returns a handle to a message catalog by
       *  returning do_open(s, loc).
       *
       *  @param  s  The catalog to open.
       *  @param  loc  Locale to use for character set conversions.
       *  @return  Handle to the catalog or value < 0 if open fails.
      */
      catalog
      open(const basic_string<char>& __s, const locale& __loc) const
      { return this->do_open(__s, __loc); }

      // Non-standard and unorthodox, yet effective.
      /*
       *  @brief  Open a message catalog.
       *
       *  This non-standard function opens and returns a handle to a message
       *  catalog by returning do_open(s, loc).  The third argument provides a
       *  message catalog root directory for gnu gettext and is ignored
       *  otherwise.
       *
       *  @param  s  The catalog to open.
       *  @param  loc  Locale to use for character set conversions.
       *  @param  dir  Message catalog root directory.
       *  @return  Handle to the catalog or value < 0 if open fails.
      */
      catalog
      open(const basic_string<char>&, const locale&, const char*) const;

      /*
       *  @brief  Look up a string in a message catalog.
       *
       *  This function retrieves and returns a message from a catalog by
       *  returning do_get(c, set, msgid, s).
       *
       *  For gnu, @a set and @a msgid are ignored.  Returns gettext(s).
       *  For default, returns s. For ieee, returns catgets(c,set,msgid,s).
       *
       *  @param  c  The catalog to access.
       *  @param  set  Implementation-defined.
       *  @param  msgid  Implementation-defined.
       *  @param  s  Default return value if retrieval fails.
       *  @return  Retrieved message or @a s if get fails.
      */
      string_type
      get(catalog __c, int __set, int __msgid, const string_type& __s) const
      { return this->do_get(__c, __set, __msgid, __s); }

      /*
       *  @brief  Close a message catalog.
       *
       *  Closes catalog @a c by calling do_close(c).
       *
       *  @param  c  The catalog to close.
      */
      void
      close(catalog __c) const
      { return this->do_close(__c); }

    protected:
      /// Destructor.
      virtual
      ~messages();

      /*
       *  @brief  Open a message catalog.
       *
       *  This function opens and returns a handle to a message catalog in an
       *  implementation-defined manner.  This function is a hook for derived
       *  classes to change the value returned.
       *
       *  @param  s  The catalog to open.
       *  @param  loc  Locale to use for character set conversions.
       *  @return  Handle to the opened catalog, value < 0 if open failed.
      */
      virtual catalog
      do_open(const basic_string<char>&, const locale&) const;

      /*
       *  @brief  Look up a string in a message catalog.
       *
       *  This function retrieves and returns a message from a catalog in an
       *  implementation-defined manner.  This function is a hook for derived
       *  classes to change the value returned.
       *
       *  For gnu, @a set and @a msgid are ignored.  Returns gettext(s).
       *  For default, returns s. For ieee, returns catgets(c,set,msgid,s).
       *
       *  @param  c  The catalog to access.
       *  @param  set  Implementation-defined.
       *  @param  msgid  Implementation-defined.
       *  @param  s  Default return value if retrieval fails.
       *  @return  Retrieved message or @a s if get fails.
      */
      virtual string_type
      do_get(catalog, int, int, const string_type& __dfault) const;

      /*
       *  @brief  Close a message catalog.
       *
       *  @param  c  The catalog to close.
      */
      virtual void
      do_close(catalog) const;

      // Returns a locale and codeset-converted string, given a char* message.
      char*
      _M_convert_to_char(const string_type& __msg) const
      {
        // XXX
        return reinterpret_cast<char*>(const_cast<_CharT*>(__msg.c_str()));
      }

      // Returns a locale and codeset-converted string, given a char* message.
      string_type
      _M_convert_from_char(char*) const
      {
#if 0
        // Length of message string without terminating null.
        size_t __len = char_traits<char>::length(__msg) - 1;

        // "everybody can easily convert the string using
        // mbsrtowcs/wcsrtombs or with iconv()"

        // Convert char* to _CharT in locale used to open catalog.
        // XXX need additional template parameter on messages class for this..
        // typedef typename codecvt<char, _CharT, _StateT> __codecvt_type;
        typedef typename codecvt<char, _CharT, mbstate_t> __codecvt_type;

        __codecvt_type::state_type __state;
        // XXX may need to initialize state.
        //initialize_state(__state._M_init());

        char* __from_next;
        // XXX what size for this string?
        _CharT* __to = static_cast<_CharT*>(__builtin_alloca(__len + 1));
        const __codecvt_type& __cvt = use_facet<__codecvt_type>(_M_locale_conv);
        __cvt.out(__state, __msg, __msg + __len, __from_next,
                  __to, __to + __len + 1, __to_next);
        return string_type(__to);
#endif
#if 0
        typedef ctype<_CharT> __ctype_type;
        // const __ctype_type& __cvt = use_facet<__ctype_type>(_M_locale_msg);
        const __ctype_type& __cvt = use_facet<__ctype_type>(locale());
        // XXX Again, proper length of converted string an issue here.
        // For now, assume the converted length is not larger.
        _CharT* __dest = static_cast<_CharT*>(__builtin_alloca(__len + 1));
        __cvt.widen(__msg, __msg + __len, __dest);
        return basic_string<_CharT>(__dest);
#endif
        return string_type();
      }
     };

  template<typename _CharT>
    locale::id messages<_CharT>::id;

  // Specializations for required instantiations.
  template<>
    string
    messages<char>::do_get(catalog, int, int, const string&) const;

#ifdef _GLIBCXX_USE_WCHAR_T
  template<>
    wstring
    messages<wchar_t>::do_get(catalog, int, int, const wstring&) const;
#endif

   /// class messages_byname [22.2.7.2].
   template<typename _CharT>
    class messages_byname : public messages<_CharT>
    {
    public:
      typedef _CharT                    char_type;
      typedef basic_string<_CharT>      string_type;

      explicit
      messages_byname(const char* __s, size_t __refs = 0);

    protected:
      virtual
      ~messages_byname()
      { }
    };

_GLIBCXX_END_NAMESPACE

// Include host and configuration specific messages functions.
#include <bits/messages_members.h>

// 22.2.1.5  Template class codecvt
#include <bits/codecvt.h>

#ifndef _GLIBCXX_EXPORT_TEMPLATE
# include <bits/locale_facets_nonio.tcc>
#endif

#endif