30.8 Outline Mode
Outline mode is a major mode much like Text mode but intended for
editing outlines. It allows you to make parts of the text temporarily
invisible so that you can see the outline structure. Type M-x
outline-mode to switch to Outline mode as the major mode of the current
buffer.
When Outline mode makes a line invisible, the line does not appear
on the screen. The screen appears exactly as if the invisible line
were deleted, except that an ellipsis (three periods in a row) appears
at the end of the previous visible line. (Multiple consecutive
invisible lines produce just one ellipsis.)
Editing commands that operate on lines, such as C-n and
C-p, treat the text of the invisible line as part of the previous
visible line. Killing the ellipsis at the end of a visible line
really kills all the following invisible lines.
Outline minor mode provides the same commands as the major mode,
Outline mode, but you can use it in conjunction with other major modes.
Type M-x outline-minor-mode to enable the Outline minor mode in
the current buffer. You can also specify this in the text of a file,
with a file local variable of the form ‘mode: outline-minor’
(see File Variables).
The major mode, Outline mode, provides special key bindings on the
C-c prefix. Outline minor mode provides similar bindings with
C-c @ as the prefix; this is to reduce the conflicts with the
major mode's special commands. (The variable
outline-minor-mode-prefix controls the prefix used.)
Entering Outline mode runs the hook text-mode-hook followed by
the hook outline-mode-hook (see Hooks).
