Re: Bug: property drawers within code blocks interfere [8.2.2 (8.2.2-elpa @ /home/tod/.emacs.d/.cask/24.3.50.1/elpa/org-20131108/)]

[Nicolas Goaziou <n.goaziou@gmail.com>]

Bastien <bzg@gnu.org> writes:

> Hi Aaron and Tod,
>
> Aaron Ecay <aaronecay@gmail.com> writes:
>
>> This seems like an excellent use case for the parser: basically a bunch
>> of uses of org-*-regexp and org-re-property need to be augmented with
>> a check like:
>> (not (memq (org-element-type (org-element-at-point)) '(src-block example-block ...)))
>>
>> A better alternative might be to use the parser to find the property
>> drawer in the first place (instead of a regex).  Either way, it seems
>> like the best strategy might be to fix all uses of these problem
>> variables at once, which is a big undertaking.
>
> Also don't forget the cost in terms of speed.  It's fine to fix the
> behavior of Org for such cases, but those cases are rare, and could
> be explicitely prevented.  If the general fix does not slow down the
> parsing too much, then I'm all for it.  Nicolas might have better
> insight here than me.

With newly introduced parser cache, the cost is amortized when using
`org-element-at-point' and `org-element-context'. With a little care,
the overhead is negligible. Therefore, these functions should be used
whenever possible.

I'm slowly working on introducing these functions in basic parts of Org
(e.g. fontification, indentation). Then I will target other functions
not using them yet. There's a lot to do. Help is welcome. IMO, at the
bare minimum, new or rewritten functions should use them.

For example, a way to correctly find the property drawer associated to
the current section is to use something like the following:

  (save-excursion
    (outline-previous-heading)
    (unless (bobp)
      (let ((limit (save-excursion (outline-next-heading) (point))))
        (catch 'exit
          (while (re-search-forward org-property-start-re limit t)
            (let ((drawer (org-element-at-point)))
              (when (eq (org-element-type drawer) 'property-drawer)
                ...
                (throw 'exit ...))))))))


Regards,

-- 
Nicolas Goaziou