Re: Does secondary filtering allow multiple tags?

[Hsiu-Khuern Tang <hsiu-khuern.tang@hp.com>]

* On Fri 07:38AM +0000, 09 Jan 2009, Carsten Dominik (dominik@science.uva.nl) wrote:
> 
> On Jan 9, 2009, at 2:55 AM, Hsiu-Khuern Tang wrote:
> 
> > Hi all,
> >
> > Suppose I have tagged some of my TODO headings.  In an agenda view,  
> > is it
> > currently possible to filter (using org-agenda-filter-by-tag) all  
> > entries that
> > are tagged with (say) either "project1" _or_ "project2"?  One can  
> > certainly do
> > "project1" _and_ "project2" by narrowing the filter.
> 
> No.
> 
> - Carsten

Here's a workaround.  I use org-map-entries to select all headlines directly
tagged with "project1" or "project2" and tag them with something unique, say
"CUR".  Then I can use the ordinary filter mechanism in an agenda view to
restrict to headlines tagged with "CUR".

,----
| (setq cur_tags '("project1" "project2"))
| 
| ;; Unbind the variable
| ;; (makunbound 'cur_tags)
| 
| (setq match_string (concat "+TAGS={" (mapconcat (lambda (x) x)
| 						cur_tags "\|") "}"))
| 
| ;; Remove the "CUR" tag:
| (org-map-entries '(org-toggle-tag "CUR") "CUR" 'agenda)
| 
| ;; Turn on the CUR tag for all headlines (directly) tagged with
| ;; any member of cur_tags
| (org-map-entries '(org-toggle-tag "CUR" 'on) match_string 'agenda)
| 
| ;; Count the number of headlines (directly) tagged with any member of
| ;; cur_tags:
| (length (org-map-entries t match_string 'agenda))
`----

Maybe someone will find this useful, or think of a more elegant solution.

-- 
Best,
Hsiu-Khuern.