= Recur =

The recur module provides iterators for datetime objects. Recurrence patterns can be provided in natural language strings like "every 3 days" or "Sept 14" (currently, only a English Locale is provided). For example, this code:

{{{d = recur.Recurrence(datetime.date(1999, 11, 28), "-5 each month")}}}

Will make "d" an iterator, producing datetime.date objects starting with {{{datetime.date(1999, 12, 26)}}}, and then proceeding to the fifth-from-last date of each succeeding month.

You can see the main module here: source:/recur.py, and there's a test module here: source:/test_recur.py.

== The Worker class ==

The recur module now includes a Worker class, which spawns new threads as needed to accomplish recurring tasks. Subclass it and override its "work" method. You can set its "paused" and "terminated" attributes to True/False as needed to manage a recurring task.

(N.B. -- Python 2.3.5 and 2.4.1 have some issues when spawning new threads in a subinterpreter, like those found in mod_python. If you find (as I did) that Worker threads are being created but not executed, check your Python version. See the [http://sourceforge.net/tracker/index.php?func=detail&aid=1163563&group_id=5470&atid=105470 Sourceforge ticket] for more details.)

== FAQ ==

'''Q: How can I run a Worker task only once?'''

A1: In the "work" method (which you need to override), set self.terminated to True. You should probably do this ''before'' performing the work, in case the time to perform the work is actually longer than the recurrence cycle.

A2: Provide a Recurrence object (instead of a recurrence string) and set its endDate.