Function is_infinity

extern/boost/boost/date_time/date.hpp:121–124

check to see if date is one of the infinity values

    }
    //! check to see if date is one of the infinity values
    BOOST_CONSTEXPR bool is_infinity()  const
    {
      return traits_type::is_inf(days_);
    }
    //! check to see if date is greater than all possible dates
    BOOST_CONSTEXPR bool is_pos_infinity()  const
    {