(allout-regexp, allout-line-boundary-regexp)

(allout-bob-regexp): Correct grouping and boundaries to fix backwards traversal.
(allout-depth-specific-regexp, allout-depth-one-regexp): New versions that
exploit \\{M\\} regexp syntax, to avoid geometric or worse time in
allout-ascend.
(allout-doublecheck-at-and-shallower): Identify depth threshold below which
topics are checked for and disqualified by containment discontinuities.
(allout-hotspot-key-handler): Correctly handle multiple-key strokes.  Remove
some unused variables.
(allout-mode-leaders): Clarify that mode-specific comment-start will be used
(set-allout-regexp): Correctly regexp-quote allout regexps to properly accept
alternative header-leads and primary bullets with regexp-specific characters
(eg, C "/*", mathematica "(*").
Include new regular expressions among those configured.
(allout-infer-header-lead-and-primary-bullet): Rename allout-infer-header-lead.
(allout-recent-depth): Manifest as a variable as well as a function.
(allout-prefix-data): Simplify into an inline instead of a macro, assuming
current match data rather than being explicitly passed it.  Establish
allout-recent-depth value as well as allout-recent-prefix-beginning and
allout-recent-prefix-end.
(allout-aberrant-container-p): True when an item's immediate offspring
discontinuously contained.  Useful for disqualifying unintended topic prefixes,
likely at low depths.
(allout-goto-prefix-doublechecked): Elaborated version of allout-goto-prefix
which disqualifies aberrant pseudo-items.
(allout-pre-next-prefix): Layer on top of lower-level routines, to get
disqualification of aberrant containers.
(allout-end-of-prefix, allout-end-of-subtree): Disqualify aberrant containers.
(allout-beginning-of-current-entry): Position at start of buffer when in
container (depth 0) entry.
(nullify-allout-prefix-data): Invalidate allout-recent-* prefix data.
(allout-current-bullet): Strip text properties.
(allout-get-prefix-bullet): Use right match groups.
(allout-beginning-of-line, allout-next-heading): Disqualify aberrant containers.
(allout-previous-heading): Disqualify aberrant containers, and change to
regular (rather than inline) function, to allow self-recursion.
(allout-get-invisibility-overlay): Increment so progress is made when the first
overlay is not the sought one.
(allout-end-of-prefix): Disqualify aberrant containers.
(allout-end-of-line): Cycle something like allout-beginning-of-line.
(allout-mode): Make allout-old-style-prefixes (ie, enabling use with outline.el
outlines) functional again.  Change the primary bullet along with the
header-lead - level 1 new-style bullets now work.
Engage allout-before-change-handler in mainline emacs, not just xemacs, to do
undo handling.
(allout-before-change-handler): Expose undo changes occurring in hidden
regions.  Use allout-get-invisibility-overlay instead of reimplementing it
inline.
(allout-chart-subtree): Use start rather than end of prefix in charts.  Use
allout-recent-depth variable.
(allout-chart-siblings): Disqualify aberrant topics.
(allout-beginning-of-current-entry): Position correctly.
(allout-ascend): Use new allout-depth-specific-regexp and
allout-depth-one-regexp for linear instead of O(N^2) or worse behavior.
(allout-ascend-to-depth): Depend on allout-ascend, rather than reimplementing
an algorithm.
(allout-up-current-level): Depend on allout-ascend, rather than reimplementing
an algorithm.  Return to start-point if we fail.
(allout-descend-to-depth): Use allout-recent-depth variable instead of function.
(allout-next-sibling): On traversal of numerous intervening topics, resort to
economical allout-next-sibling-leap.
(allout-next-sibling-leap): Specialized version of allout-next-sibling that
uses allout-ascend cleverly, to depend on a regexp search to leap large numbers
of contained topics, rather than arbitrarily many one-by-one traversals.
(allout-next-visible-heading): Disqualify aberrant topics.
(allout-previous-visible-heading): Position consistently when interactive.
(allout-forward-current-level): Base on allout-previous-sibling rather than
 (differently) reimplmenting the algorithm.  Remove some unused variables.
(allout-solicit-alternate-bullet): Present default choice stripped of text
properties.
(allout-rebullet-heading): Use bullet stripped of text properties.
Register changes using allout-exposure-change-hook.  Disregard aberrant topics.
(allout-shift-in): With universal-argument, make topic a peer of it's former
offspring.  Simplify the code by separating out allout-shift-out functionality.
(allout-shift-out): With universal-argument, make offspring peers of their
former container, and its siblings.  Implement the functionality here, rather
than inappropriately muddling the implementation of allout-shift-in.
(allout-rebullet-topic): Respect additional argument for new parent-child
separation function.
(allout-yank-processing): Use allout-ascend directly.
(allout-show-entry): Disqualify aberrant topics.
(allout-show-children): Handle discontinuous children gracefully, extending the
depth being revealed to expose them and posting a message indicating the
situation.
(allout-show-to-offshoot): Remove obsolete and incorrect comment.  Leave cursor
in correct position.
(allout-hide-current-subtree): Use allout-ascend directly.  Disqualify aberrant
topics.
(allout-kill-line, allout-kill-topic): Preserve exposure layout in a way that
the yanks can restore it, as used to happen.
(allout-yank-processing): Restore exposure layout as recorded by allout-kill-*,
as used to happen.
(allout-annotate-hidden, allout-hide-by-annotation): New routines for preseving
and restoring exposure layout across kills.
(allout-toggle-subtree-encryption): Run allout-exposure-change-hook.
(allout-encrypt-string): Strip text properties.  Rearranged order and
outline-headings for some of the miscellaneous functions.
(allout-resolve-xref): No need to quote the error name in the condition-case
handler section.
(allout-flatten): Classic recursive (and recursively intensive, without
tail-recursion) list-flattener, needed by allout-shift-out when confronted with
discontinuous children.

lisp/allout.el

@@ -2442,7 +2442,8 @@ We skip anomolous low-level topics, a la `allout-aberrant-container-p'."
   (when (re-search-forward allout-line-boundary-regexp nil 0)
     (allout-prefix-data)
     (and (<= allout-recent-depth allout-doublecheck-at-and-shallower)
-         ;; register non-aberrant or disqualifying offspring as allout-recent-*
+         ;; this will set allout-recent-* on the first non-aberrant topic,
+         ;; whether it's the current one or one that disqualifies it:
          (allout-aberrant-container-p))
     (goto-char allout-recent-prefix-beginning)))
 ;;;_   > allout-this-or-next-heading
@@ -2452,7 +2453,7 @@ We skip anomolous low-level topics, a la `allout-aberrant-container-p'."
   ;; and usable by allout-mode.
   (if (not (allout-goto-prefix-doublechecked)) (allout-next-heading)))
 ;;;_   > allout-previous-heading ()
-(defsubst allout-previous-heading ()
+(defun allout-previous-heading ()
   "Move to the prior \(possibly invisible) heading line.
 
 Return the location of the beginning of the heading, or nil if not found.
@@ -2470,10 +2471,11 @@ We skip anomolous low-level topics, a la `allout-aberrant-container-p'."
         (if (and (<= allout-recent-depth allout-doublecheck-at-and-shallower)
                  (allout-aberrant-container-p))
             (or (allout-previous-heading)
-                (goto-char start-point)
-                ;; recalibrate allout-recent-*:
-                (allout-depth)))
-        (point)))))
+                (and (goto-char start-point)
+                     ;; recalibrate allout-recent-*:
+                     (allout-depth)
+                     nil))
+          (point))))))
 ;;;_   > allout-get-invisibility-overlay ()
 (defun allout-get-invisibility-overlay ()
   "Return the overlay at point that dictates allout invisibility."
@@ -2721,9 +2723,9 @@ otherwise skip white space between bullet and ensuing text."
 (defun allout-current-bullet-pos ()
   "Return position of current \(visible) topic's bullet."
 
- (if (not (allout-current-depth))
+  (if (not (allout-current-depth))
       nil
-   (1- allout-recent-prefix-end)))
+    (1- allout-recent-prefix-end)))
 ;;;_   > allout-back-to-current-heading ()
 (defun allout-back-to-current-heading ()
   "Move to heading line of current topic, or beginning if already on the line.
@@ -2752,8 +2754,8 @@ in which case we return nil."
 
 Returns that character position."
 
-  (if (re-search-forward allout-line-boundary-regexp nil 'move)
-      (goto-char (1- (allout-prefix-data)))))
+  (if (allout-next-heading)
+      (goto-char (1- allout-recent-prefix-beginning))))
 ;;;_   > allout-end-of-subtree (&optional current include-trailing-blank)
 (defun allout-end-of-subtree (&optional current include-trailing-blank)
   "Put point at the end of the last leaf in the containing topic.
@@ -2863,7 +2865,7 @@ collapsed."
   "Ascend one level, returning t if successful, nil if not."
   (prog1
       (if (allout-beginning-of-level)
-	  (allout-previous-heading))
+          (allout-previous-heading))
     (if (interactive-p) (allout-end-of-prefix))))
 ;;;_   > allout-descend-to-depth (depth)
 (defun allout-descend-to-depth (depth)
@@ -2887,11 +2889,13 @@ Returning depth if successful, nil if not."
 (defun allout-up-current-level (arg)
   "Move out ARG levels from current visible topic."
   (interactive "p")
-  (allout-back-to-current-heading)
-  (if (not (allout-ascend))
-      (error "Can't ascend past outermost level")
-    (if (interactive-p) (allout-end-of-prefix))
-    allout-recent-prefix-beginning))
+  (let ((start-point (point)))
+    (allout-back-to-current-heading)
+    (if (not (allout-ascend))
+        (progn (goto-char start-point)
+               (error "Can't ascend past outermost level"))
+      (if (interactive-p) (allout-end-of-prefix))
+      allout-recent-prefix-beginning)))
 
 ;;;_  - Linear
 ;;;_   > allout-next-sibling (&optional depth backward)
@@ -6531,8 +6535,8 @@ If BEG is bigger than END we return 0."
   "Return a list of all atoms in list."
   ;; classic.
   (cond ((null list) nil)
-        ((atom (car list)) (cons (car list) (flatten (cdr list))))
-        (t (append (flatten (car list)) (flatten (cdr list))))))
+        ((atom (car list)) (cons (car list) (allout-flatten (cdr list))))
+        (t (append (allout-flatten (car list)) (allout-flatten (cdr list))))))
 ;;;_  : Compatability:
 ;;;_   > allout-mark-marker to accommodate divergent emacsen:
 (defun allout-mark-marker (&optional force buffer)