Re: Exporter: Derived backend options-alist

[Nicolas Goaziou <mail@nicolasgoaziou.fr>]

Hello,

James Harkins <jamshark70@qq.com> writes:

> I'm trying to derive an exporter backend from ASCII. I need to add some export options, so I have:
>
> #+BEGIN_SRC {emacs-lisp}
> (org-export-define-derived-backend 'scdoc 'ascii
>   :translate-alist  ... omitted for brevity...
>   :options-alist
>   '((:categories "CATEGORIES" nil nil t)
>     (:related "RELATED" nil nil t)
>     (:summary "SUMMARY" nil nil t)
>     (:redirect "REDIRECT" nil nil t))
> )
>
> ... snip snip...
>
> (defun org-scdoc-template (contents info)
>   "Return complete document string after SCDoc conversion.
> CONTENTS is the transcoded contents string.  INFO is a plist
> holding export options."
>   (let* ((title (org-export-data (plist-get info :title) info))
> 	(categories (org-export-data (plist-get info :categories) info))
> 	(related (org-export-data (plist-get info :related) info))
> 	(summary (org-export-data (plist-get info :summary) info))
> 	(redirect (org-export-data (plist-get info :redirect) info))
> 	(output (format "TITLE:: %s\n" title)))
>     (if categories (setq output (concat output (format "CATEGORIES:: %s\n" categories))))
>     (if related (setq output (concat output (format "RELATED:: %s\n" categories))))
>     (if summary (setq output (concat output (format "SUMMARY:: %s\n" categories))))
>     (if redirect (setq output (concat output (format "REDIRECT:: %s\n" categories))))
>     (concat output "\n\n" contents)))
> #+END_SRC
>
> (Pardon the un-idiomatic Emacs-lisp.)
>
> Then I created an org file that begins:
>
> #+BEGIN_SRC org
>   ,#+title:: PulseCount
>   ,#+summary:: Pulse counter.
>   ,#+related:: Classes/Stepper
>   ,#+categories:: UGens>Triggers

It should be 

  #+title: PulseCount
  ...
  #+categories: UGens>Triggers

>
>   ,* Description
>   Each trigger increments a counter which is output as a signal.
> #+END_SRC
>
> Then I run org-scdoc-export-as-scdoc, and I get as the first few lines:
>
> TITLE:: 
> CATEGORIES:: 
> RELATED:: 
> SUMMARY:: 
> REDIRECT:: 
>
> ... telling me that the template function retrieved empty strings for
> all the export options.

`org-export-data' always returns a string, even with a nil first
argument. If categories, related, etc. values are not parsed, just use

  (categories (plist-get info :categories))
  

Regards,

-- 
Nicolas Goaziou