On Sat, Nov 10, 2018 at 1:58 PM Nicolas Goaziou <mail@nicolasgoaziou.fr> wrote:

Hello,

John Kitchin <jkitchin@andrew.cmu.edu> writes:

> You can retrieve keywords in the org-file like this:
>
> (defun get-keyword (key)
> (org-element-map (org-element-parse-buffer) 'keyword
> (lambda (k)
> (when (string= key (org-element-property :key k))
> (org-element-property :value k)))
> nil t))

As a minor addendum,

(org-element-parse-buffer 'element)

is more efficient in this case.

An even more efficient way to retrieve keywords, assuming buffer is not
already parsed, would be:

(org-with-point-at 1
(let ((case-fold-search t)
(regexp (format "^[ \t]*#\\+%s:" key))
(result nil))
(while (re-search-forward regexp nil t)
(let ((element (org-element-at-point)))
(when (eq 'keyword (org-element-type element))
(push (org-element-property :value element) result))))
result))

This is very helpful, Nicolas and John.

What about *setting* a global keyword? I would like to write something like this:

(defun org-lms-set-global-prop-value (key value)
"Add or update keyword KEY in the org file header."
(save-excursion
(goto-char (point-min))
(insert (format "#+%s: %" (upcase key) value))))

But

(a) insert the value at the *end* of the headers section, not the beginning.

(b) preferably replace any existing values of the keyword rather than write a whole new line.

(b) I guess could be achieved with something like

(replace-regexp (format "\(^[ \t]*#\\+%s: \)\(.*\)" key) (concat "\1" value))

But what about (a)? I thought org already had a couple of functions that performed this kind of serach but now I'm not so sure.

Regards,

--
Nicolas Goaziou