// In header: <boost/log/expressions/formatters/date_time.hpp>
template<typename T, typename FallbackPolicyT, typename CharT, 
         template< typename > class ActorT = phoenix::actor> 
class format_date_time_actor :
  public ActorT< format_date_time_terminal< T, FallbackPolicyT, CharT > >
{
public:
  // types
  typedef T                                                                   value_type;               // Attribute value type. 
  typedef CharT                                                               char_type;                // Character type. 
  typedef FallbackPolicyT                                                     fallback_policy;          // Fallback policy. 
  typedef format_date_time_terminal< value_type, fallback_policy, char_type > terminal_type;            // Base terminal type. 
  typedef terminal_type::formatter_function_type                              formatter_function_type;  // Formatter function. 
  typedef ActorT< terminal_type >                                             base_type;                // Base actor type. 
  // construct/copy/destruct
  explicit format_date_time_actor(base_type const &);
  // public member functions
  attribute_name get_name() const;
  fallback_policy const & get_fallback_policy() const;
  formatter_function_type const & get_formatter_function() const;
};