allout-expose-topic is an interactive compiled Lisp function in `allout.el'.

(allout-expose-topic SPEC)

Apply exposure specs to successive outline topic items.

Use the more convenient frontend, `allout-new-exposure', if you don't
need evaluation of the arguments, or even better, the `allout-layout'
variable-keyed mode-activation/auto-exposure feature of allout outline
mode. See the respective documentation strings for more details.

Cursor is left at start position.

SPEC is either a number or a list.

Successive specs on a list are applied to successive sibling topics.

A simple spec (either a number, one of a few symbols, or the null
list) dictates the exposure for the corresponding topic.

Non-null lists recursively designate exposure specs for respective
subtopics of the current topic.

The `:' repeat spec is used to specify exposure for any number of
successive siblings, up to the trailing ones for which there are
explicit specs following the `:'.

Simple (numeric and null-list) specs are interpreted as follows:

Numbers indicate the relative depth to open the corresponding topic.
- negative numbers force the topic to be closed before opening to the
absolute value of the number, so all siblings are open only to
that level.
- positive numbers open to the relative depth indicated by the
number, but do not force already opened subtopics to be closed.
- 0 means to close topic -- hide all offspring.
: - `repeat'
apply prior element to all siblings at current level, *up to*
those siblings that would be covered by specs following the `:'
on the list. Ie, apply to all topics at level but the last
ones. (Only first of multiple colons at same level is
respected -- subsequent ones are discarded.)
* - completely opens the topic, including bodies.
+ - shows all the sub headers, but not the bodies
- - exposes the body of the corresponding topic.

(allout-expose-topic '(-1 : 0))
Close this and all following topics at current level, exposing
only their immediate children, but close down the last topic
at this current level completely.
(allout-expose-topic '(-1 () : 1 0))
Close current topic so only the immediate subtopics are shown;
show the children in the second to last topic, and completely
close the last one.
(allout-expose-topic '(-2 : -1 *))
Expose children and grandchildren of all topics at current
level except the last two; expose children of the second to
last and completely open the last one.