Variable: display-fill-column-indicator-mode

display-fill-column-indicator-mode is a buffer-local variable defined in display-fill-column-indicator.el.gz.

Documentation

Non-nil if Display-Fill-Column-Indicator mode is enabled.

Use the command display-fill-column-indicator-mode(var)/display-fill-column-indicator-mode(fun) to change this variable.

View in manual

Probably introduced at or before Emacs version 28.1.

Key Bindings

Source Code

;; Defined in /usr/src/emacs/lisp/display-fill-column-indicator.el.gz
;;;###autoload
(define-minor-mode display-fill-column-indicator-mode
  "Toggle display of `fill-column' indicator.
This uses `display-fill-column-indicator' internally.

To change the position of the column displayed by default
customize `display-fill-column-indicator-column'.  You can change the
character for the indicator setting `display-fill-column-indicator-character'.
The globalized version is `global-display-fill-column-indicator-mode',
which see.
This minor mode assumes the buffer uses a fixed-pitch font; if you
use variable-pitch fonts, the indicators on different lines might
not appear aligned.
See Info node `Displaying Boundaries' for details."
  :lighter nil
  (if display-fill-column-indicator-mode
      (progn
        (setq display-fill-column-indicator t)
        (unless display-fill-column-indicator-character
          (setq display-fill-column-indicator-character
                (if (and (char-displayable-p ?\u2502)
                         (or (not (display-graphic-p))
                             (eq (aref (query-font (car (internal-char-font nil ?\u2502))) 0)
                                 (face-font 'default))))
                    ?\u2502
                  ?|)))
        (if display-fill-column-indicator-warning
            (add-hook 'post-command-hook #'fill-indicator--set-warning nil t)))
    (if display-fill-column-indicator-warning
        (remove-hook 'post-command-hook #'fill-indicator--set-warning t))
    (setq display-fill-column-indicator nil)))