boost::date_time::ymd_order_spec — Enum for distinguishing the order of Month, Day, & Year.
// In header: <boost/date_time/parse_format_base.hpp> enum ymd_order_spec { ymd_order_iso, ymd_order_dmy, ymd_order_us };
Enum for distinguishing the order in which Month, Day, & Year will appear in a date string
