ignoreheading in LaTeX export

ignoreheading in LaTeX export

[Alan Schmitt]

Hello,

I need to ignore a heading during a LaTeX export (I don't want the
"section" command to be generated, but I need the text to be included;
the heading is there because the previous one is tagged with "export").
I found this solution:

https://stackoverflow.com/questions/10295177/is-there-an-equivalent-of-org-modes-b-ignoreheading-for-non-beamer-documents

Is it still the way to go?

Thanks,

Alan

Re: ignoreheading in LaTeX export

[Nicolas Goaziou]

Hello,

Alan Schmitt <alan.schmitt@polytechnique.org> writes:

> I need to ignore a heading during a LaTeX export (I don't want the
> "section" command to be generated, but I need the text to be included;
> the heading is there because the previous one is tagged with "export").
> I found this solution:
>
> https://stackoverflow.com/questions/10295177/is-there-an-equivalent-of-org-modes-b-ignoreheading-for-non-beamer-documents
>
> Is it still the way to go?

You can use a hook or a filter to remove the headline. I would use
a hook in this case. See (info "(org) Advanced configuration"), the
first example, with an appropriate MATCH argument for `org-map-entries'.


Regards,

-- 
Nicolas Goaziou

Re: ignoreheading in LaTeX export

[Sebastien Vauban]

Nicolas Goaziou wrote:
> Alan Schmitt <alan.schmitt-o/5/jSaJEHk+NdeTPqioyti2O/JbrIOy@public.gmane.org> writes:
>
>> I need to ignore a heading during a LaTeX export
>
> You can use a hook or a filter to remove the headline. I would use
> a hook in this case.

Could you explain why you would choose a hook?  What's guiding your
choice?

Thanks!

> See (info "(org) Advanced configuration"), the first example, with an
> appropriate MATCH argument for `org-map-entries'.

Best regards,
  Seb

-- 
Sebastien Vauban

Re: ignoreheading in LaTeX export

[Nicolas Goaziou]

Sebastien Vauban <sva-news-D0wtAvR13HarG/iDocfnWg@public.gmane.org>
writes:

> Could you explain why you would choose a hook?  What's guiding your
> choice?

The fact that I work in the Org buffer and can use `org-map-entries',
which trivializes the problem here. OTOH, a filter works at the LaTeX
code level and ignoreheading tag may be missing (removed by some other
filter, tags ignored, etc).


Regards,

-- 
Nicolas Goaziou

Re: ignoreheading in LaTeX export

[Alan Schmitt]

Nicolas Goaziou <n.goaziou@gmail.com> writes:

> Hello,
>
> Alan Schmitt <alan.schmitt@polytechnique.org> writes:
>
>> I need to ignore a heading during a LaTeX export (I don't want the
>> "section" command to be generated, but I need the text to be included;
>> the heading is there because the previous one is tagged with "export").
>> I found this solution:
>>
>> https://stackoverflow.com/questions/10295177/is-there-an-equivalent-of-org-modes-b-ignoreheading-for-non-beamer-documents
>>
>> Is it still the way to go?
>
> You can use a hook or a filter to remove the headline. I would use
> a hook in this case. See (info "(org) Advanced configuration"), the
> first example, with an appropriate MATCH argument for `org-map-entries'.

Thanks a lot for the suggestion, here is what I ended up doing:

#+begin_src emacs-lisp
  (defun as/delete-ignored-heading (backend)
    "Remove every headline with a tag `ignoreheading' in the
  current buffer. BACKEND is the export back-end being used, as
  a symbol."
    (org-map-entries
     (lambda () 
       (when (member "ignoreheading" (org-get-tags-at nil t))
         (lambda () (delete-region (point) (progn (forward-line) (point))))))))

  (setq org-export-before-parsing-hook '(as/delete-ignored-heading))
#+end_src

It works great.

I have a followup question (purely from an aesthetic point of view, the
code works fine). I see that a label is still generated in the LaTeX
file (there is a "\label{sec-1}" with just the "\maketitle" above it).
Is it expected?

Thanks again,

Alan

Re: ignoreheading in LaTeX export

[Nicolas Goaziou]

Alan Schmitt <alan.schmitt@polytechnique.org> writes:

> Thanks a lot for the suggestion, here is what I ended up doing:
>
> #+begin_src emacs-lisp
>   (defun as/delete-ignored-heading (backend)
>     "Remove every headline with a tag `ignoreheading' in the
>   current buffer. BACKEND is the export back-end being used, as
>   a symbol."
>     (org-map-entries
>      (lambda () 
>        (when (member "ignoreheading" (org-get-tags-at nil t))
>          (lambda () (delete-region (point) (progn (forward-line) (point))))))))
>
>   (setq org-export-before-parsing-hook '(as/delete-ignored-heading))
> #+end_src

I suggest to use the dedicated MATCH argument for `org-map-entries':

  (defun as/delete-ignored-heading (backend)
      "Remove every headline with a tag `ignoreheading' in the
    current buffer. BACKEND is the export back-end being used, as
    a symbol."
      (org-map-entries
       (lambda () (delete-region (point) (progn (forward-line) (point))))
       "+ignoreheading"))

> I have a followup question (purely from an aesthetic point of view, the
> code works fine). I see that a label is still generated in the LaTeX
> file (there is a "\label{sec-1}" with just the "\maketitle" above it).
> Is it expected?

I don't think so. Though, after a quick test, I'm unable to reproduce
it. Do you have an ECM?


Regards,

-- 
Nicolas Goaziou

Re: ignoreheading in LaTeX export

[Alan Schmitt]

Nicolas Goaziou <n.goaziou@gmail.com> writes:

> I suggest to use the dedicated MATCH argument for `org-map-entries':
>
>   (defun as/delete-ignored-heading (backend)
>       "Remove every headline with a tag `ignoreheading' in the
>     current buffer. BACKEND is the export back-end being used, as
>     a symbol."
>       (org-map-entries
>        (lambda () (delete-region (point) (progn (forward-line) (point))))
>        "+ignoreheading"))

Thank you, this works, with a big caveat (which makes this approach
broken for me): with the following ECM

--8<---------------cut here---------------start------------->8---
* No Export                                                        :noexport:

test

* Heading 1                                                   :ignoreheading:

foo

* Heading 2

bar
--8<---------------cut here---------------end--------------->8---

the text under "Heading 1" is no longer present. I suspect the heading is
removed before the ":noexport:" is processed, which captures the text as
well (which is bad: the reason for the heading in the first place is to
end the ":noexport:" block). I went back to the stack-overflow
suggestion.

>> I have a followup question (purely from an aesthetic point of view, the
>> code works fine). I see that a label is still generated in the LaTeX
>> file (there is a "\label{sec-1}" with just the "\maketitle" above it).
>> Is it expected?
>
> I don't think so. Though, after a quick test, I'm unable to reproduce
> it. Do you have an ECM?

It is indeed a problem with the stack-overflow solution and not with
yours. I was confused when trying things out.

Thanks,

Alan

Re: ignoreheading in LaTeX export

[Rasmus]

Alan Schmitt <alan.schmitt@polytechnique.org> writes:

> Nicolas Goaziou <n.goaziou@gmail.com> writes:
>
>> I suggest to use the dedicated MATCH argument for `org-map-entries':
>>
>>   (defun as/delete-ignored-heading (backend)
>>       "Remove every headline with a tag `ignoreheading' in the
>>     current buffer. BACKEND is the export back-end being used, as
>>     a symbol."
>>       (org-map-entries
>>        (lambda () (delete-region (point) (progn (forward-line) (point))))
>>        "+ignoreheading"))
>
> Thank you, this works, with a big caveat (which makes this approach
> broken for me): with the following ECM
>
> * No Export                                                        :noexport:
>
> test
>
> * Heading 1                                                   :ignoreheading:
>
> foo
>
> * Heading 2
>
> bar
>
> the text under "Heading 1" is no longer present. I suspect the heading is
> removed before the ":noexport:" is processed, which captures the text as
> well (which is bad: the reason for the heading in the first place is to
> end the ":noexport:" block). I went back to the stack-overflow
> suggestion.

This is why you would want to use a filter rather than a hook
(i.e. you only want to retain the Org structure when exporting).
Here's a slightly modified version of the filter I use.  It sucks, but
ignoreheading is quite hard to get right, especially outside of LaTeX.
Note the comment in the first defun!  If you are unhappy with that
limitation you can use a regexp to look for ignoreheading in the first
line of org-ignoreheading function.  I think I even have an old
version somewhere that uses a regexp.

(defun rasmus/get-org-headline-string-element  (headline backend info)
  "Return the org element representation of an element.

Will NOT work with headlines like this one, that has no text-properties

* =verb="
  (let ((prop-point (next-property-change 0 headline)))
    (if prop-point (plist-get (text-properties-at prop-point headline) :parent))))
      

(defun rasmus/org-latex-ignoreheading (headline backend info)
  "Strip headline from HEADLINE if it has tag ignoreheading.

Somewhat broken for ascii. . .
"
  (when (org-export-derived-backend-p backend 'latex 'ascii)
    (let ((tags
           (org-element-property :tags
                                 (rasmus/get-org-headline-string-element headline backend info))))
      (when (and tags (member-ignore-case "ignoreheading" tags))
        (string-match "\\`.*\n.*\n" headline)
        (replace-match "" nil nil headline)))))

(add-to-list 'org-export-filter-headline-functions
               'rasmus/org-latex-ignoreheading)


—Rasmus

-- 
Sådan en god dansk lagereddike kan man slet ikke bruge mere

Re: ignoreheading in LaTeX export

[Alan Schmitt]

Hi Rasmus,

Rasmus <rasmus@gmx.us> writes:

> This is why you would want to use a filter rather than a hook
> (i.e. you only want to retain the Org structure when exporting).
> Here's a slightly modified version of the filter I use.

Thank you for this suggestion.

I went back to my original problem (how to neatly fold away some setup
code at the beginning of the file) and I'm now using a solution that
seems to work well.

- The setup heading has a 'ignoreheading' tag (there is no longer
  a 'noexport' tag).
- Code blocks inside have a ':exports none' header.
- The next block where I want to add some heading-less text also has
  a 'ignoreheading' tag.
- I'm using the "before-parsing" hook to get rid of these headings.

Thanks again,

Alan

Re: ignoreheading in LaTeX export

[Marcin Borkowski]

Dnia 2014-03-27, o godz. 09:23:06
Alan Schmitt <alan.schmitt@polytechnique.org> napisał(a):

> Hello,
> 
> I need to ignore a heading during a LaTeX export (I don't want the
> "section" command to be generated, but I need the text to be included;
> the heading is there because the previous one is tagged with
> "export"). I found this solution:
> 
> https://stackoverflow.com/questions/10295177/is-there-an-equivalent-of-org-modes-b-ignoreheading-for-non-beamer-documents
> 
> Is it still the way to go?

Just my 2 cents: you could always go for a /really/ dirty hack and do
it on the LaTeX side.  AFAIR, tags end up somewhere in the title of the
section, so you can /redefine/ the =\section= macro to recognize that
and do nothing in that case.  This is most probably an overkill, but
the general rule (maybe) worth remembering would be: if you want to
tweak something with LaTeX export, it /might/ be possible that it would
be (a) doable and maybe even (b) reasonable to do it on the LaTeX side.

> Thanks,
> 
> Alan

Hth,

-- 
Marcin Borkowski
http://octd.wmi.amu.edu.pl/en/Marcin_Borkowski
Adam Mickiewicz University