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/* Copyright (c) 2004 CrystalClear Software, Inc.
 * Use, modification and distribution is subject to the 
 * Boost Software License, Version 1.0. (See accompanying
 * file LICENSE_1_0.txt or
 * Author: Jeff Garland
 * $Date$

#include <vector>
#include <string>
#include <iterator>
#include "boost/date_time/special_defs.hpp"

namespace boost { namespace date_time {

  //! Class that provides generic formmatting ostream formatting for special values
  /*! This class provides for the formmating of special values to an output stream.
   *  In particular, it produces strings for the values of negative and positive
   *  infinity as well as not_a_date_time.  
   *  While not a facet, this class is used by the date and time facets for formatting
   *  special value types.
  template <class CharT, class OutItrT = std::ostreambuf_iterator<CharT, std::char_traits<CharT> > >
  class special_values_formatter  
    typedef std::basic_string<CharT> string_type;
    typedef CharT                    char_type;
    typedef std::vector<string_type> collection_type;
    static const char_type default_special_value_names[3][17];

    //! Construct special values formatter using default strings.
    /*! Default strings are not-a-date-time -infinity +infinity

    //! Construct special values formatter from array of strings
    /*! This constructor will take pair of iterators from an array of strings
     *  that represent the special values and copy them for use in formatting
     *  special values.  
     *  const char* const special_value_names[]={"nadt","-inf","+inf" };
     *  special_value_formatter svf(&special_value_names[0], &special_value_names[3]);
    special_values_formatter(const char_type* const* begin, const char_type* const* end) 
      std::copy(begin, end, std::back_inserter(m_special_value_names));
    special_values_formatter(typename collection_type::iterator beg, typename collection_type::iterator end)
      std::copy(beg, end, std::back_inserter(m_special_value_names));

    OutItrT put_special(OutItrT next, 
                        const boost::date_time::special_values& value) const 
      unsigned int index = value;
      if (index < m_special_value_names.size()) {
      return next;
    collection_type m_special_value_names;

  //! Storage for the strings used to indicate special values 
  /* using c_strings to initialize these worked fine in testing, however,
   * a project that compiled its objects separately, then linked in a separate
   * step wound up with redefinition errors for the values in this array.
   * Initializing individual characters eliminated this problem */
  template <class CharT, class OutItrT>  
  const typename special_values_formatter<CharT, OutItrT>::char_type special_values_formatter<CharT, OutItrT>::default_special_value_names[3][17] = { 
    {'+','i','n','f','i','n','i','t','y'} };

 } } //namespace boost::date_time