text: #ifndef GREG_DURATION_HPP___
  #define GREG_DURATION_HPP___
  
  /* Copyright (c) 2002,2003 CrystalClear Software, Inc.
   * Use, modification and distribution is subject to the 
   * Boost Software License, Version 1.0. (See accompanying
   * file LICENSE-1.0 or http://www.boost.org/LICENSE-1.0)
   * Author: Jeff Garland, Bart Garst 
   * $Date: 2007/02/12 18:25:14 $
   */
  
  #include "boost/date_time/date_duration.hpp"
  #if defined(BOOST_DATE_TIME_OPTIONAL_GREGORIAN_TYPES)
  #include "boost/date_time/date_duration_types.hpp"
  #endif
  #include "boost/date_time/int_adapter.hpp"
  
  
  namespace boost {
  namespace gregorian {
  
  
    //!An internal date representation that includes infinities, not a date
    typedef boost::date_time::duration_traits_adapted date_duration_rep;
  
    //! Durations in days for gregorian system
    /*! \ingroup date_basics
     */
    typedef date_time::date_duration<date_duration_rep> date_duration;
  
    //! Shorthand for date_duration
    typedef date_duration days;
  
  } } //namespace gregorian
  
  
  
  #endif
  