Re: [O] org-e-latex: ignoreheading is not working any more.

[Myles English]

Hi Nicolas,

Nicolas Goaziou writes:

> Hello,
>
> Myles English <address@hidden> writes:
>
>> Hi Yagnesh,
>>
>> Yagnesh Raghava Yakkala writes:
>>> I have been using example setting suggested by Nicolas
>>> (http://article.gmane.org/gmane.emacs.orgmode/55972) to tell exporter to 
>>> skip
>>> particular headline (with ignoreheading tag).
>>>
>>> It seems recent commit made this setup obsolete. could anybody suggest me 
>>> the
>>> alternative setting for this.?
>
> There are only two changes:
>
> #+BEGIN_SRC emacs-lisp
> (add-to-list 'org-e-latex-translate-table '(headline . my-e-latex-headline))
> #+END_SRC
>
> is obsolete since `org-e-latex-translate-table' variable has been
> removed. If you want to install a new translator, you have to create
> a derived back-end, which is easy (see the example at the end of that
> link).
>
> Also, the hook will now be called with an argument: the back-end used as
> a symbol.
>
> Otherwise, the thread is still valid.
>
>> I've been using this, (I notice it is significantly longer than the
>> example in the link above so it may be overkill):
>>
>> #+BEGIN_SRC emacs-lisp
>> (defun my-export-delete-headlines-tagged-noheading(heading-text)
>>     "Goto headline `heading-text'"
>>     (let ((wasfound t))
>>       (while wasfound
>>         (progn (org-element-map
>>                 (org-element-parse-buffer 'headline)
>>                 'headline
>>                 (lambda (x)
>>                   (if (member "noheading" (org-element-property :tags x))
>>                       (progn
>>                         (goto-char (org-element-property :begin x))
>>                         (delete-region (point)
>>                                        (progn
>>                                          (forward-line 1)
>>                                          (point)))
>>                         (goto-char (point-min)))
>>                     (setq wasfound nil)))
>>                 nil
>>                 t)) ;; stop at first find,
>>         nil)        ;; start again from the top of the buffer
>>       (goto-char (point-min))))
>>   
>>   (add-to-list 'org-export-before-processing-hook
>>                'my-export-delete-headlines-tagged-noheading)
>> #+END_SRC
>
> Each time you delete an headline, you parse the full buffer again, so,
> yes, it will be slow. You can simply reverse list returned by
> `org-element-map' (but don't stop at first find) and walk that list,
> deleting matching headlines along the way.

[kicks self]

> #+begin_src emacs-lisp
> (defun my-export-delete-headlines-tagged-noheading (backend)
>   (dolist (hl (nreverse (org-element-map (org-element-parse-buffer 'headline)
>                                          'headline
>                                          'identity)))
>     (when (member "noheading" (org-element-property :tags hl))
>       (goto-char (org-element-property :begin hl))
>       (delete-region (point) (progn (forward-line) (point))))))
> #+end_src
>
> Another option is to use `org-map-entries', which doesn't require to
> reverse the results (and doesn't use Org Element). This is left as an
> exercise.

Thank you, there is lots of useful stuff to learn from in your reply, as
always.

Myles