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       1             : 
       2             : #ifndef DATETIME_SPECIAL_VALUE_FORMATTER_HPP___
       3             : #define DATETIME_SPECIAL_VALUE_FORMATTER_HPP___
       4             : 
       5             : /* Copyright (c) 2004 CrystalClear Software, Inc.
       6             :  * Use, modification and distribution is subject to the 
       7             :  * Boost Software License, Version 1.0. (See accompanying
       8             :  * file LICENSE_1_0.txt or http://www.boost.org/LICENSE_1_0.txt)
       9             :  * Author: Jeff Garland
      10             :  * $Date$
      11             :  */
      12             : 
      13             : #include <vector>
      14             : #include <string>
      15             : #include "boost/date_time/special_defs.hpp"
      16             : 
      17             : namespace boost { namespace date_time {
      18             : 
      19             : 
      20             :   //! Class that provides generic formmatting ostream formatting for special values
      21             :   /*! This class provides for the formmating of special values to an output stream.
      22             :    *  In particular, it produces strings for the values of negative and positive
      23             :    *  infinity as well as not_a_date_time.  
      24             :    *
      25             :    *  While not a facet, this class is used by the date and time facets for formatting
      26             :    *  special value types.
      27             :    *
      28             :    */
      29             :   template <class CharT, class OutItrT = std::ostreambuf_iterator<CharT, std::char_traits<CharT> > >
      30           0 :   class special_values_formatter  
      31             :   {
      32             :   public:
      33             :     typedef std::basic_string<CharT> string_type;
      34             :     typedef CharT                    char_type;
      35             :     typedef std::vector<string_type> collection_type;
      36             :     static const char_type default_special_value_names[3][17];
      37             : 
      38             :     //! Construct special values formatter using default strings.
      39             :     /*! Default strings are not-a-date-time -infinity +infinity
      40             :      */
      41           0 :     special_values_formatter() 
      42           0 :     {
      43           0 :       std::copy(&default_special_value_names[0], 
      44             :                 &default_special_value_names[3], 
      45           0 :                 std::back_inserter(m_special_value_names));      
      46           0 :     }
      47             : 
      48             :     //! Construct special values formatter from array of strings
      49             :     /*! This constructor will take pair of iterators from an array of strings
      50             :      *  that represent the special values and copy them for use in formatting
      51             :      *  special values.  
      52             :      *@code
      53             :      *  const char* const special_value_names[]={"nadt","-inf","+inf" };
      54             :      *
      55             :      *  special_value_formatter svf(&special_value_names[0], &special_value_names[3]);
      56             :      *@endcode
      57             :      */
      58             :     special_values_formatter(const char_type* const* begin, const char_type* const* end) 
      59             :     {
      60             :       std::copy(begin, end, std::back_inserter(m_special_value_names));
      61             :     }
      62             :     special_values_formatter(typename collection_type::iterator beg, typename collection_type::iterator end)
      63             :     {
      64             :       std::copy(beg, end, std::back_inserter(m_special_value_names));
      65             :     }
      66             : 
      67           0 :     OutItrT put_special(OutItrT next, 
      68             :                         const boost::date_time::special_values& value) const 
      69             :     {
      70             :       
      71           0 :       unsigned int index = value;
      72           0 :       if (index < m_special_value_names.size()) {
      73           0 :         std::copy(m_special_value_names[index].begin(), 
      74           0 :                   m_special_value_names[index].end(),
      75             :                   next);
      76             :       }
      77           0 :       return next;
      78             :     }
      79             :   protected:
      80             :     collection_type m_special_value_names;
      81             :   };
      82             : 
      83             :   //! Storage for the strings used to indicate special values 
      84             :   /* using c_strings to initialize these worked fine in testing, however,
      85             :    * a project that compiled its objects separately, then linked in a separate
      86             :    * step wound up with redefinition errors for the values in this array.
      87             :    * Initializing individual characters eliminated this problem */
      88             :   template <class CharT, class OutItrT>  
      89             :   const typename special_values_formatter<CharT, OutItrT>::char_type special_values_formatter<CharT, OutItrT>::default_special_value_names[3][17] = { 
      90             :     {'n','o','t','-','a','-','d','a','t','e','-','t','i','m','e'},
      91             :     {'-','i','n','f','i','n','i','t','y'},
      92             :     {'+','i','n','f','i','n','i','t','y'} };
      93             : 
      94             :  } } //namespace boost::date_time
      95             : 
      96             : #endif