2024-01-21 15:03:08-05:00 - Don't want a line to break in emacs even in auto-fill-mode?

Have you ever been editing a file in emacs where there a specific lines that should not be wrapped, but you are using auto-fill-mode and they accidently get wrapped? The emacs variable fill-nobreak-predicate is your friend!

;; Nikola metadata lines start like this:
;; .. keyword:
;; They shouldn't tbe wrapped.
(defvar tkb-nikola-metadata-regexp "\\.\\. [a-z]+:")

(defun tkb-nikola-rest-fill-nobreak-p ()
  "Don't fill on metadata lines in nikola reST posts."
    (looking-at tkb-nikola-metadata-regexp)))

(defun tkb-nikola-rest-hook ()
  (when (and (string-match "\\.rst\\'" (buffer-file-name))
             (looking-at tkb-nikola-metadata-regexp))
    (make-local-variable 'fill-nobreak-predicate)
    (setq fill-nobreak-predicate (list #'tkb-nikola-rest-fill-nobreak-p))))

(add-to-list 'find-file-hook #'tkb-nikola-rest-hook)

Here's a gist where you can comment on it.