Function: auto-fill-mode

auto-fill-mode is an interactive and byte-compiled function defined in simple.el.gz.

Signature

(auto-fill-mode &optional ARG)

Documentation

Toggle automatic line breaking (Auto Fill mode).

When Auto Fill mode is enabled, inserting a space at a column beyond current-fill-column automatically breaks the line at a previous space.

When auto-fill-mode is on, the auto-fill-function(var)/auto-fill-function(fun) variable is non-nil.

The value of normal-auto-fill-function specifies the function to use for auto-fill-function(var)/auto-fill-function(fun) when turning Auto Fill mode on.

This is a minor mode. If called interactively, toggle the Auto-Fill mode mode. If the prefix argument is positive, enable the mode, and if it is zero or negative, disable the mode.

If called from Lisp, toggle the mode if ARG is toggle. Enable the mode if ARG is nil, omitted, or is a positive number. Disable the mode if ARG is a negative number.

To check whether the minor mode is enabled in the current buffer, evaluate auto-fill-function(var)/auto-fill-function(fun).

The mode's hook is called both when the mode is enabled and when it is disabled.

View in manual

Probably introduced at or before Emacs version 19.29.

Key Bindings

Aliases

idlwave-auto-fill-mode (obsolete since 28.1) fortran-auto-fill-mode (obsolete since 29.1)

Source Code

;; Defined in /usr/src/emacs/lisp/simple.el.gz
(define-minor-mode auto-fill-mode
  "Toggle automatic line breaking (Auto Fill mode).

When Auto Fill mode is enabled, inserting a space at a column
beyond `current-fill-column' automatically breaks the line at a
previous space.

When `auto-fill-mode' is on, the `auto-fill-function' variable is
non-nil.

The value of `normal-auto-fill-function' specifies the function to use
for `auto-fill-function' when turning Auto Fill mode on."
  :variable (auto-fill-function
             . (lambda (v) (setq auto-fill-function
                            (if v normal-auto-fill-function)))))