Match data clobbered by buffer modification hooks

Question

I want to setup a Journal entry template that prompts for a date/time, so that I can process current entries, as well as older ones.

This is what I have so far:

;;; Org-capture settings
(setq org-capture-templates
      '(("j" "Journal" entry (file+olp+datetree "~/org/journal.org")
         "* %U\n%?" :time-prompt t :empty-lines 1)))

;;; Set keyboard shortcut
(global-set-key (kbd "C-c c") 'org-capture)

The trouble is, when I run the capture template, any date I select that is earlier than what is already in the datetree produces the following error:

Any ideas?

Answer 1

The error message

Match data clobbered by buffer modification hooks

is caused by functions in the hooks before-change-functions or after-change-functions modifying the match data. That may happen if these functions call search-forward and friends or looking-at and friends directly or indirectly through calling other functions.

Solve this problem by wrapping the body of these functions in (save-match-data ...).

The info manual says about that in Section 31.28 "Change Hooks":

The functions you use in these hooks should save and restore the match data if they do anything that uses regular expressions; otherwise, they will interfere in bizarre ways with the editing operations that call them.