is a variable defined in `
Its value is
- Automatically becomes buffer-local when set.
- This variable is safe as a file local variable if its value
satisfies the predicate `stringp'.
Leading string which helps distinguish topic headers.
Outline topic header lines are identified by a leading topic
header prefix, which mostly have the value of this var at their front.
Level 1 topics are exceptions. They consist of only a single
character, which is typically set to the `allout-primary-bullet'.
You can customize this variable.