Resolve Org bookmark links on export

Replace bookmark links on export with their actual targets, as the bookmarks itself are of little
use in the final document.

init.el

@@ -718,6 +718,7 @@ split horizontally again, but this extra work should not matter much."
              org-password-manager-get-password-by-id
              db/org-bookmark-open
              db/org-bookmark-store-link
+             db/org-bookmark-export
              db/org-lint-invalid-bookmark-link
              db/org-lint-possible-bookmark-link))
 
@@ -1016,7 +1017,8 @@ split horizontally again, but this extra work should not matter much."
                                                                 number))))
             (org-link-set-parameters "bookmark"
 			             :follow #'db/org-bookmark-open
-			             :store #'db/org-bookmark-store-link)
+			             :store #'db/org-bookmark-store-link
+                                     :export #'db/org-bookmark-export)
             (when (eq system-type 'windows-nt)
               (org-link-set-parameters "onenote" :follow #'db/org-onenote-open)
               (org-link-set-parameters "outlook" :follow #'db/org-outlook-open))

site-lisp/db-org.el

@@ -482,7 +482,7 @@ Via %%(with-temp-buffer (db/org-add-link-to-current-clock) (string-trim (buffer-
 
 (defun db/find-parent-task ()
   ;; http://doc.norang.ca/org-mode.html#Clocking
-  "Return point of the nearest parent task, and NIL if no such task exists.
+  "Return point of the nearest parent task, and nil if no such task exists.
 
 Ignores headlines tagged with NOP or PERIODIC, as those items
 should not be clocked."
@@ -2262,6 +2262,23 @@ PARAMS may contain the following values:
       (org-link-store-props :link (concat "bookmark:" bookmark)
 			    :description bookmark))))
 
+(defun db/org-bookmark-export (path description backend)
+  "Export Org bookmark links by resolving them to their target path.
+
+PATH denotes the bookmark name, while DESCRIPTION is the (optional)
+description of that link.  BACKEND denotes the target format for export."
+  (condition-case err
+      (let* ((bmk-target (or (bookmark-prop-get path 'location)
+                             (bookmark-prop-get path 'filename)
+                             (user-error "Cannot resolve bookmark for export: %s"
+                                         path))))
+        ;; TODO: the following might be quite heavy, as it invokes the Org parser again.  Maybe
+        ;; exporting links can be done more easily?
+        (org-export-string-as (org-link-make-string bmk-target description)
+                              backend))
+    (error (error "Error of type “%s” while exporting bookmark “%s”: “%s”"
+                  (car err) path (cadr err)))))
+
 (defun db/org-lint-invalid-bookmark-link (ast)
   "Org lint checker to verify bookmark links in AST point to known bookmarks."
   (bookmark-maybe-load-default-file)