Re: org-agenda queries for absent properties

[Ihor Radchenko <yantar92@posteo.net>]

Jens Schmidt <jschmidt4gnu@vodafonemail.de> writes:

> On 2023-07-31  08:45, Ihor Radchenko wrote:
>
>> If you are up to a job of adding this to `org-make-tags-matcher' and
>> not breaking things, you can try.
>
> Depends a bit on the required collateral changes: Updating ORG-NEWS and
> doc/org-guide.org should be no problem.  Doing a naive grep-based search
> I haven't found tests on `org-tags-view' or `org-make-tags-matcher', so
> I hopefully wouldn't need to add anything new in that direction.

There are some tests in testing/lisp/test-org.el:test-org/map-entries
If we add new feature, we should better add test coverage for it as
well. Should not be hard.

> Finally, the first step probably would be to make that humongous regexp
> in `org-make-tags-matcher' a bit more readable.

Agree.

> ... What would you prefer?
> `rx' or sth long the following lines (not checked for equality yet):
>    (re (concat
>         ;; AND operator (OR is done by global splitting)
> ...

`rx' would be great.
But even adding comments like in your example would be an improvement.

>  > But we should really provide more
>  > readable match syntax, similar to org-ql; sooner or later.
>
> Agreed on that if the new syntax will allow for equally succinct
> queries.  Plus a very cursory, doc-only review of org-ql hasn't
> revealed to me how I'd do numeric property comparisons with it.

Similar does not mean the same :)
I am thinking about something like
https://github.com/alphapapa/org-ql#non-sexp-query-syntax

For example, org-ql has

(src :lang "elisp" :regexps ("defun"))
and
src:defun,lang=elisp

We may as well allow >,<,... in addition to =.

I had this in mind for a wile, but I am still hoping that we can
eventually (when it is added to Emacs) rely upon peg.el for parsing.
https://yhetil.org/emacs-devel/875yvtbbn3.fsf@ericabrahamsen.net/

-- 
Ihor Radchenko // yantar92,
Org mode contributor,
Learn more about Org mode at <https://orgmode.org/>.
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