Variable: speedbar-tag-group-name-minimum-length

speedbar-tag-group-name-minimum-length is a customizable variable defined in speedbar.el.gz.

Value

4

Documentation

The minimum length of a prefix group name before expanding.

Thus, if the speedbar-tag-hierarchy-method includes prefix-group and one such groups common characters is less than this number of characters, then the group name will be changed to the form of:
  worda to wordb
instead of just
  word
This way we won't get silly looking listings.

Source Code

;; Defined in /usr/src/emacs/lisp/speedbar.el.gz
(defcustom speedbar-tag-group-name-minimum-length 4
  "The minimum length of a prefix group name before expanding.
Thus, if the `speedbar-tag-hierarchy-method' includes `prefix-group'
and one such groups common characters is less than this number of
characters, then the group name will be changed to the form of:
  worda to wordb
instead of just
  word
This way we won't get silly looking listings."
  :group 'speedbar
  :type 'integer)