Re: # of parameters of `org-latex-format-headline-function'

[Nick Dokos <ndokos@gmail.com>]

Sebastien Vauban <sva-news@mygooglest.com>
writes:

> Hello,
>
> During the summer, the number of parameters of the
> `org-latex-format-headline-function' changed from 5 to 6: addition of
> `info'.
>
> The new version of my private formatting function is:
>
>   ;; function for formatting the headline's text
>   (setq org-latex-format-headline-function
>         'my/org-latex-format-headline)
>
>   ;; markup for TODO keywords and for tags, as a printf format
>   (defun my/org-latex-format-headline (todo todo-type priority text tags info)
>     "Default function for formatting the headline's text."
>     (concat (when todo
>               (format "{%s\\textbf{\\textsc{\\textsf{%s}}}} "
>                       (cond ((equal todo-type 'todo) "\\color{red}")
>                             ((equal todo-type 'done) "\\color{teal}")
>                             (t "\\color{gray}"))
>                       todo))
>             (when priority
>               (format "\\framebox{\\#%c} " priority))
>             text
>             (when tags
>               (format "\\hfill{}\\fbox{\\textsc{%s}}"
>                 (mapconcat 'identity tags ":")))))
>
> That works on `master', but not on Org from ELPA (`maint').
>
> As parts of my config file are shared between my coworkers, and as some
> of them don't have Git Org but the ELPA package, how can I support both
> versions of Org?
>
> Do I have to test the Org version number, or is there a more clever way?
>

Make info an &optional parameter in your function: recent org will call
it with a non-nil info, old org will call it without an info parameter
(which I believe will make it nil inside your function).

Untested.

Nick