Re: [O] org-calendar-holiday and local holidays

[Alexis]

On 2015-03-03T08:58:20+1100, Jorge A. Alfaro-Murillo 
<jorge.alfaro-murillo@yale.edu> said:

JAA> holidays.el appends holiday-local-holidays to 
calendar-holidays JAA> via a defcustom, so if you set 
holiday-local-holidays in your JAA> .emacs, restart emacs and the 
local holidays are not in JAA> calendar-holidays, it is because 
you are calling something that JAA> loads holidays.el before you 
set holiday-local-holidays.

JAA> If you add the code above to your .emacs and later modify 
your JAA> configuration and remove or move the part that loads 
JAA> holidays.el, then either your code will fail (because JAA> 
calendar-holidays is not yet defined) or calendar-holidays will 
JAA> have your local holidays twice and they will show twice in 
your JAA> agenda.

JAA> I think that you should look for whatever calls holidays.el 
and JAA> set holiday-local-holidays before that.

i just tried moving my `(setq holiday-local-holidays ...)` to the 
very first line of my config setup, and lo, that does result in 
local holidays appearing in my Org agenda. However, my config 
setup is a 3000+ line Org Babel file, in which i group together 
things that are related in my mind, and the setup for the calendar 
is about a third of the way through this. Thus ....

JAA> If not, then at least use eval-after-load so that JAA> 
calendar-holidays is already defined when the code is run, and 
JAA> add-to-list so that the entries do not get added twice if 
they are JAA> already there:

JAA> #+BEGIN_SRC emacs-lisp (eval-after-load 'holidays '(dolist 
JAA> (holiday holiday-local-holidays) (add-to-list 
'calendar-holidays JAA> holiday)) #+END_SRC

.... works better in my context, and is more robust, longer-term, 
than my original suggestion to use

   (setq calendar-holidays (append calendar-holidays 
   holiday-local-holidays)) 

So, thank you! Although i do note that my suggestion was 
nevertheless within the guidelines of the documentation for 
`calendar-holidays`:

   Note that these variables have no effect on 
   `calendar-holidays' after it has been set (e.g. after the 
   calendar is loaded).  In that case, customize 
   `calendar-holidays' directly.

i feel the above documentation could be improved by adding that 
`eval-after-load` should probably by used in this context, e.g.:

   Note that these variables have no effect on 
   `calendar-holidays' after it has been set (e.g. after the 
   calendar is loaded).  In that case, customize 
   `calendar-holidays' directly, for example by using 
   `eval-after-load':

       (eval-after-load 'holidays
                        '(dolist (holiday holiday-local-holidays)
                                  (add-to-list 'calendar-holidays 
                                  holiday)))

i'll open a GNU Emacs issue to that effect. :-)

Thanks again!


Alexis.