This constants are provided for convenience. In the C++ sources, enumeration types are used for days of the week, months of the year as well as the ordering terms.
Similar package-level constants are provided here as well. This should be considered as experimental and may be withdrawn in a later version of the package.
Sun, Mon, Tue, ..., Sat can be used instead of the values 0 to 6.
Jan, Feb, ..., Dec can be used instead of the values 1 to 12.
first, second, ..., fifth can be used instead of the values 1 to 5.
We use the same values as the Boost source code. In other words, Sunday is 0, Monday is 1 and so on. Months, however, start at 1 for January.
Boost Date_Time: http://www.boost.org/doc/html/date_time.html