20.1.3.3 Outline Visibility Commands

The other special commands of outline mode are used to make lines visible or invisible. Their names all start with hide or show. Most of them exist as pairs of opposites. They are not undoable; instead, you can undo right past them. Making lines visible or invisible is simply not recorded by the undo mechanism.

M-x hide-body

Make all body lines in the buffer invisible.

M-x show-all

Make all lines in the buffer visible.

C-c C-d

Make everything under this heading invisible, not including this heading itself (hide-subtree).

C-c C-s

Make everything under this heading visible, including body, subheadings, and their bodies (show-subtree).

M-x hide-leaves

Make the body of this heading line, and of all its subheadings, invisible.

M-x show-branches

Make all subheadings of this heading line, at all levels, visible.

C-c C-i

Make immediate subheadings (one level down) of this heading line visible (show-children).

M-x hide-entry

Make this heading line’s body invisible.

M-x show-entry

Make this heading line’s body visible.

Two commands that are exact opposites are M-x hide-entry and M-x show-entry. They are used with point on a heading line, and apply only to the body lines of that heading. The subtopics and their bodies are not affected.

Two more powerful opposites are C-c C-d (hide-subtree) and C-c C-s (show-subtree). Both should be used when point is on a heading line, and both apply to all the lines of that heading’s subtree: its body, all its subheadings, both direct and indirect, and all of their bodies. In other words, the subtree contains everything following this heading line, up to and not including the next heading of the same or higher rank.

Intermediate between a visible subtree and an invisible one is having all the subheadings visible but none of the body. There are two commands for doing this, one that hides the bodies and one that makes the subheadings visible. They are M-x hide-leaves and M-x show-branches.

A little weaker than show-branches is C-c C-i (show-children). It makes just the direct subheadings visible—those one level down. Deeper subheadings remain invisible.

Two commands have a blanket effect on the whole file. M-x hide-body makes all body lines invisible, so that you see just the outline structure. M-x show-all makes all lines visible. You can think of these commands as a pair of opposites even though M-x show-all applies to more than just body lines.

You can turn off the use of ellipses at the ends of visible lines by setting selective-display-ellipses to nil. The result is no visible indication of the presence of invisible lines.