CLOSED: [2017-01-15 Sun 12:58]
:PROPERTIES:
:ID: 2017-01-15-org-clone-subtree-with-time-shift
:CREATED:  [2017-01-15 Sun 12:06]
:END:
:LOGBOOK:
- State "DONE"       from "NEXT"       [2017-01-15 Sun 12:58]
:END:

Silent update 2019-09-25: added to [[id:2019-09-25-using-orgmode][blog series "Using Org Mode Features"]]

Please do read [[id:2019-09-25-using-orgmode][my "Using Org Mode Features" (UOMF) series page]] for
explanations on articles of this series.

[[http://orgmode.org/manual/Timestamps.html#Timestamps][Org-mode has time-stamps]] which can be written manually or added via
[[http://orgmode.org/manual/Creating-timestamps.html#Creating-timestamps][commands like]] =C-c .= (=org-time-stamp()=). Note that I am using
[[http://orgmode.org/manual/Timestamps.html#Timestamps][inactive time-stamps]] (brackets instead of angle brackets) in this blog
entry to prevent my agenda from showing all those example time-stamps:

: [2017-01-15 Sun] day
: [2017-01-15 Sun 12:19] time
: [2017-01-15 Sun 12:19-15:00] time period
: [2017-01-15 Sun]-[2017-01-17 Tue] date period
: [2017-01-15 Sun]--[2017-01-17 Tue] date period (alternative style)

When a task or an event is repeated again and again, Org is able to
[[http://orgmode.org/manual/Repeated-tasks.html#Repeated-tasks][express it for most cases]] as well:

: [2017-01-15 Sun +1w] every sunday
: [2017-01-15 Sun +3d] every three days starting with this sunday
: [2017-01-15 Sun .+1w] every week after the day this task was finished
: [2017-01-15 Sun ++1w] like .+1 but it stays on the next Sunday after finishing

Complex recurring items can be defined using special [[https://www.gnu.org/software/emacs/manual/html_node/emacs/Sexp-Diary-Entries.html][sexp diary]]
entries:

: * 22:00-23:00 The nerd meeting on every 2nd Thursday of the month
: [%%(diary-float t 4 2)]

However, for many standard recurring events (like =+1w=) and for
everything advanced where I'd need sexp expressions, I do prefer a
different approach: =M-x org-clone-subtree-with-time-shift=

And this is why.

*** The Problem with Repeater Intervals

Let's assume, we are joining a volleyball team which has a training on
Monday 7pm to 8:30pm. This can be easily defined like:

: * [2017-01-16 Mon 19:00-20:30 +1w] Volleyball training

This creates a recurring event on the agenda.

There are several issues with this approach:

What about cancellations or school holidays, where there is no sports
hall available?

I'd have the recurring event on my agenda without the possibility to
define exceptions.

Further more, when I want to add notes to specific trainings, I'd end
up with a very long body for this single training heading.

*** Org-Knowledge to the Rescue

To prevent all those issues mentioned above, I use =M-x
org-clone-subtree-with-time-shift= (or =C-c C-x c= if you can remember
it).

You simply create one instance of your event without any repeater
interval and invoke =M-x org-clone-subtree-with-time-shift=. Then, Org
asks you how many copies it should create and an optional time-shift
between those instances.

With our volleyball example, this would look like that:

: * [2017-01-16 Mon 19:00-20:30] Volleyball training

Then invoke =M-x org-clone-subtree-with-time-shift=, ask for twenty
copies (or how many weeks in advance you want to define trainings),
and a time-shift of =1w=.

Then you end up with following headings:

: * [2017-01-16 Mon 19:00-20:30] Volleyball training
: * [2017-01-23 Mon 19:00-20:30] Volleyball training
: * [2017-01-30 Mon 19:00-20:30] Volleyball training
: * [2017-02-06 Mon 19:00-20:30] Volleyball training
: [...]

Now you have in total twenty-one instances of your volleyball training
event. You are now free to delete single occurrences (canceled
trainings), delete a series of trainings (school holidays with no
hall), move single occurrences to different days (exceptions), and you
are able to add notes to single trainings more easily.

I am using this method instead of sexp expressions for advanced
recurrence definitions like «every second Tuesday of the month». I
clone an event with a almost fitting period like =+4w=. Then I
manually change the instances to fix them. I move to the months where
=+4w= did not result in the second Tuesday and use Shift left and
right to modify the time-stamp.

It is highly recommended to create a simple recurring todo scheduled
after the last clone which reminds you of creating the clones for the
next series of events.

*** A Workaround That Turned Out to Be Superior

When I started with Org-mode, I was using a Palm Pilot with a very
capable [[http://www.pimlicosoftware.com/datebk3.htm][DateBk3]] software. Since DateBk3 had easy-to-use and advanced
features for defining exceptions and irregular periods, I was
disappointed by Org-mode at first.

However, when I started to use =org-clone-subtree-with-time-shift=
with its instance copies, I began to favor this method because of the
advantages I mentioned above.