(defvar font-lock-warning-face)
(defgroup outlines nil
"Support for hierarchical outlining."
:prefix "outline-"
:group 'editing)
(defcustom outline-regexp "[*\^L]+"
"Regular expression to match the beginning of a heading.
Any line whose beginning matches this regexp is considered to start a heading.
Note that Outline mode only checks this regexp at the start of a line,
so the regexp need not (and usually does not) start with `^'.
The recommended way to set this is with a Local Variables: list
in the file it applies to. See also `outline-heading-end-regexp'."
:type '(choice regexp (const nil))
:group 'outlines)
(defcustom outline-heading-end-regexp "\n"
"Regular expression to match the end of a heading line.
You can assume that point is at the beginning of a heading when this
regexp is searched for. The heading ends at the end of the match.
The recommended way to set this is with a `Local Variables:' list
in the file it applies to."
:type 'regexp
:group 'outlines)
(defvar outline-mode-prefix-map
(let ((map (make-sparse-keymap)))
(define-key map "@" 'outline-mark-subtree)
(define-key map "\C-n" 'outline-next-visible-heading)
(define-key map "\C-p" 'outline-previous-visible-heading)
(define-key map "\C-i" 'show-children)
(define-key map "\C-s" 'show-subtree)
(define-key map "\C-d" 'hide-subtree)
(define-key map "\C-u" 'outline-up-heading)
(define-key map "\C-f" 'outline-forward-same-level)
(define-key map "\C-b" 'outline-backward-same-level)
(define-key map "\C-t" 'hide-body)
(define-key map "\C-a" 'show-all)
(define-key map "\C-c" 'hide-entry)
(define-key map "\C-e" 'show-entry)
(define-key map "\C-l" 'hide-leaves)
(define-key map "\C-k" 'show-branches)
(define-key map "\C-q" 'hide-sublevels)
(define-key map "\C-o" 'hide-other)
(define-key map "\C-^" 'outline-move-subtree-up)
(define-key map "\C-v" 'outline-move-subtree-down)
(define-key map [(control ?<)] 'outline-promote)
(define-key map [(control ?>)] 'outline-demote)
(define-key map "\C-m" 'outline-insert-heading)
map))
(defvar outline-mode-menu-bar-map
(let ((map (make-sparse-keymap)))
(define-key map [hide] (cons "Hide" (make-sparse-keymap "Hide")))
(define-key map [hide hide-other] '("Hide Other" . hide-other))
(define-key map [hide hide-sublevels] '("Hide Sublevels" . hide-sublevels))
(define-key map [hide hide-subtree] '("Hide Subtree" . hide-subtree))
(define-key map [hide hide-entry] '("Hide Entry" . hide-entry))
(define-key map [hide hide-body] '("Hide Body" . hide-body))
(define-key map [hide hide-leaves] '("Hide Leaves" . hide-leaves))
(define-key map [show] (cons "Show" (make-sparse-keymap "Show")))
(define-key map [show show-subtree] '("Show Subtree" . show-subtree))
(define-key map [show show-children] '("Show Children" . show-children))
(define-key map [show show-branches] '("Show Branches" . show-branches))
(define-key map [show show-entry] '("Show Entry" . show-entry))
(define-key map [show show-all] '("Show All" . show-all))
(define-key map [headings]
(cons "Headings" (make-sparse-keymap "Headings")))
(define-key map [headings demote-subtree]
'(menu-item "Demote subtree" outline-demote))
(define-key map [headings promote-subtree]
'(menu-item "Promote subtree" outline-promote))
(define-key map [headings move-subtree-down]
'(menu-item "Move subtree down" outline-move-subtree-down))
(define-key map [headings move-subtree-up]
'(menu-item "Move subtree up" outline-move-subtree-up))
(define-key map [headings copy]
'(menu-item "Copy to kill ring" outline-headers-as-kill
:enable mark-active))
(define-key map [headings outline-insert-heading]
'("New heading" . outline-insert-heading))
(define-key map [headings outline-backward-same-level]
'("Previous Same Level" . outline-backward-same-level))
(define-key map [headings outline-forward-same-level]
'("Next Same Level" . outline-forward-same-level))
(define-key map [headings outline-previous-visible-heading]
'("Previous" . outline-previous-visible-heading))
(define-key map [headings outline-next-visible-heading]
'("Next" . outline-next-visible-heading))
(define-key map [headings outline-up-heading]
'("Up" . outline-up-heading))
map))
(defvar outline-minor-mode-menu-bar-map
(let ((map (make-sparse-keymap)))
(define-key map [outline]
(cons "Outline"
(nconc (make-sparse-keymap "Outline")
(cdr
(apply 'append
(mapcar (lambda (x)
(if (consp x)
(cons '(--- "---") (cdr x))))
outline-mode-menu-bar-map))))))
map))
(defvar outline-mode-map
(let ((map (make-sparse-keymap)))
(define-key map "\C-c" outline-mode-prefix-map)
(define-key map [menu-bar] outline-mode-menu-bar-map)
map))
(defvar outline-font-lock-keywords
'( (eval . (list (concat "^\\(?:" outline-regexp "\\).+")
0 '(outline-font-lock-face) nil t)))
"Additional expressions to highlight in Outline mode.")
(defface outline-1
'((t :inherit font-lock-function-name-face))
"Level 1."
:group 'outlines)
(defface outline-2
'((t :inherit font-lock-variable-name-face))
"Level 2."
:group 'outlines)
(defface outline-3
'((t :inherit font-lock-keyword-face))
"Level 3."
:group 'outlines)
(defface outline-4
'((t :inherit font-lock-builtin-face))
"Level 4."
:group 'outlines)
(defface outline-5
'((t :inherit font-lock-comment-face))
"Level 5."
:group 'outlines)
(defface outline-6
'((t :inherit font-lock-constant-face))
"Level 6."
:group 'outlines)
(defface outline-7
'((t :inherit font-lock-type-face))
"Level 7."
:group 'outlines)
(defface outline-8
'((t :inherit font-lock-string-face))
"Level 8."
:group 'outlines)
(defvar outline-font-lock-faces
[outline-1 outline-2 outline-3 outline-4
outline-5 outline-6 outline-7 outline-8])
(defvar outline-font-lock-levels nil)
(make-variable-buffer-local 'outline-font-lock-levels)
(defun outline-font-lock-face ()
(save-excursion
(goto-char (match-beginning 0))
(looking-at outline-regexp)
(condition-case nil
(aref outline-font-lock-faces (1- (funcall outline-level)))
(error font-lock-warning-face))))
(defvar outline-view-change-hook nil
"Normal hook to be run after outline visibility changes.")
(defvar outline-mode-hook nil
"*This hook is run when outline mode starts.")
(defvar outline-blank-line nil
"*Non-nil means to leave unhidden blank line before heading.")
(define-derived-mode outline-mode text-mode "Outline"
"Set major mode for editing outlines with selective display.
Headings are lines which start with asterisks: one for major headings,
two for subheadings, etc. Lines not starting with asterisks are body lines.
Body text or subheadings under a heading can be made temporarily
invisible, or visible again. Invisible lines are attached to the end
of the heading, so they move with it, if the line is killed and yanked
back. A heading with text hidden under it is marked with an ellipsis (...).
Commands:\\<outline-mode-map>
\\[outline-next-visible-heading] outline-next-visible-heading move by visible headings
\\[outline-previous-visible-heading] outline-previous-visible-heading
\\[outline-forward-same-level] outline-forward-same-level similar but skip subheadings
\\[outline-backward-same-level] outline-backward-same-level
\\[outline-up-heading] outline-up-heading move from subheading to heading
\\[hide-body] make all text invisible (not headings).
\\[show-all] make everything in buffer visible.
\\[hide-sublevels] make only the first N levels of headers visible.
The remaining commands are used when point is on a heading line.
They apply to some of the body or subheadings of that heading.
\\[hide-subtree] hide-subtree make body and subheadings invisible.
\\[show-subtree] show-subtree make body and subheadings visible.
\\[show-children] show-children make direct subheadings visible.
No effect on body, or subheadings 2 or more levels down.
With arg N, affects subheadings N levels down.
\\[hide-entry] make immediately following body invisible.
\\[show-entry] make it visible.
\\[hide-leaves] make body under heading and under its subheadings invisible.
The subheadings remain visible.
\\[show-branches] make all subheadings at all levels visible.
The variable `outline-regexp' can be changed to control what is a heading.
A line is a heading if `outline-regexp' matches something at the
beginning of the line. The longer the match, the deeper the level.
Turning on outline mode calls the value of `text-mode-hook' and then of
`outline-mode-hook', if they are non-nil."
(make-local-variable 'line-move-ignore-invisible)
(setq line-move-ignore-invisible t)
(add-to-invisibility-spec '(outline . t))
(set (make-local-variable 'paragraph-start)
(concat paragraph-start "\\|\\(?:" outline-regexp "\\)"))
(set (make-local-variable 'auto-fill-inhibit-regexp) outline-regexp)
(set (make-local-variable 'paragraph-separate)
(concat paragraph-separate "\\|\\(?:" outline-regexp "\\)"))
(set (make-local-variable 'font-lock-defaults)
'(outline-font-lock-keywords t nil nil backward-paragraph))
(setq imenu-generic-expression
(list (list nil (concat "^\\(?:" outline-regexp "\\).*$") 0)))
(add-hook 'change-major-mode-hook 'show-all nil t))
(defcustom outline-minor-mode-prefix "\C-c@"
"*Prefix key to use for Outline commands in Outline minor mode.
The value of this variable is checked as part of loading Outline mode.
After that, changing the prefix key requires manipulating keymaps."
:type 'string
:group 'outlines)
(define-minor-mode outline-minor-mode
"Toggle Outline minor mode.
With arg, turn Outline minor mode on if arg is positive, off otherwise.
See the command `outline-mode' for more information on this mode."
nil " Outl" (list (cons [menu-bar] outline-minor-mode-menu-bar-map)
(cons outline-minor-mode-prefix outline-mode-prefix-map))
:group 'outlines
(if outline-minor-mode
(progn
(add-hook 'change-major-mode-hook
(lambda () (outline-minor-mode -1))
nil t)
(set (make-local-variable 'line-move-ignore-invisible) t)
(add-to-invisibility-spec '(outline . t)))
(setq line-move-ignore-invisible nil)
(remove-from-invisibility-spec '(outline . t))
(show-all)))
(defvar outline-level 'outline-level
"*Function of no args to compute a header's nesting level in an outline.
It can assume point is at the beginning of a header line and that the match
data reflects the `outline-regexp'.")
(defvar outline-heading-alist ()
"Alist associating a heading for every possible level.
Each entry is of the form (HEADING . LEVEL).
This alist is used two ways: to find the heading corresponding to
a given level and to find the level of a given heading.
If a mode or document needs several sets of outline headings (for example
numbered and unnumbered sections), list them set by set and sorted by level
within each set. For example in texinfo mode:
(setq outline-heading-alist
'((\"@chapter\" . 2) (\"@section\" . 3) (\"@subsection\" . 4)
(\"@subsubsection\" . 5)
(\"@unnumbered\" . 2) (\"@unnumberedsec\" . 3)
(\"@unnumberedsubsec\" . 4) (\"@unnumberedsubsubsec\" . 5)
(\"@appendix\" . 2) (\"@appendixsec\" . 3)...
(\"@appendixsubsec\" . 4) (\"@appendixsubsubsec\" . 5) ..))
Instead of sorting the entries in each set, you can also separate the
sets with nil.")
(make-variable-buffer-local 'outline-heading-alist)
(defun outline-level ()
"Return the depth to which a statement is nested in the outline.
Point must be at the beginning of a header line.
This is actually either the level specified in `outline-heading-alist'
or else the number of characters matched by `outline-regexp'."
(or (cdr (assoc (match-string 0) outline-heading-alist))
(- (match-end 0) (match-beginning 0))))
(defun outline-next-preface ()
"Skip forward to just before the next heading line.
If there's no following heading line, stop before the newline
at the end of the buffer."
(if (re-search-forward (concat "\n\\(?:" outline-regexp "\\)")
nil 'move)
(goto-char (match-beginning 0)))
(if (and (bolp) (or outline-blank-line (eobp)) (not (bobp)))
(forward-char -1)))
(defun outline-next-heading ()
"Move to the next (possibly invisible) heading line."
(interactive)
(if (and (bolp) (not (eobp))) (forward-char 1))
(if (re-search-forward (concat "^\\(?:" outline-regexp "\\)")
nil 'move)
(goto-char (match-beginning 0))))
(defun outline-previous-heading ()
"Move to the previous (possibly invisible) heading line."
(interactive)
(re-search-backward (concat "^\\(?:" outline-regexp "\\)")
nil 'move))
(defsubst outline-invisible-p (&optional pos)
"Non-nil if the character after point is invisible."
(get-char-property (or pos (point)) 'invisible))
(defun outline-visible ()
(not (outline-invisible-p)))
(make-obsolete 'outline-visible 'outline-invisible-p)
(defun outline-back-to-heading (&optional invisible-ok)
"Move to previous heading line, or beg of this line if it's a heading.
Only visible heading lines are considered, unless INVISIBLE-OK is non-nil."
(beginning-of-line)
(or (outline-on-heading-p invisible-ok)
(let (found)
(save-excursion
(while (not found)
(or (re-search-backward (concat "^\\(?:" outline-regexp "\\)")
nil t)
(error "before first heading"))
(setq found (and (or invisible-ok (not (outline-invisible-p)))
(point)))))
(goto-char found)
found)))
(defun outline-on-heading-p (&optional invisible-ok)
"Return t if point is on a (visible) heading line.
If INVISIBLE-OK is non-nil, an invisible heading line is ok too."
(save-excursion
(beginning-of-line)
(and (bolp) (or invisible-ok (not (outline-invisible-p)))
(looking-at outline-regexp))))
(defun outline-insert-heading ()
"Insert a new heading at same depth at point."
(interactive)
(let ((head (save-excursion
(condition-case nil
(outline-back-to-heading)
(error (outline-next-heading)))
(if (eobp)
(or (caar outline-heading-alist) "")
(match-string 0)))))
(unless (or (string-match "[ \t]\\'" head)
(not (string-match (concat "\\`\\(?:" outline-regexp "\\)")
(concat head " "))))
(setq head (concat head " ")))
(unless (bolp) (end-of-line) (newline))
(insert head)
(unless (eolp)
(save-excursion (newline-and-indent)))
(run-hooks 'outline-insert-heading-hook)))
(defun outline-invent-heading (head up)
(save-match-data
(let ((new-head (if up (substring head 0 -1)
(concat head (substring head -1)))))
(if (string-match (concat "\\`\\(?:" outline-regexp "\\)")
new-head)
new-head
(read-string (format "%s heading for `%s': "
(if up "Parent" "Demoted") head)
head nil nil t)))))
(defun outline-promote (&optional which)
"Promote headings higher up the tree.
If transient-mark-mode is on, and mark is active, promote headings in
the region (from a Lisp program, pass `region' for WHICH). Otherwise:
without prefix argument, promote current heading and all headings in the
subtree (from a Lisp program, pass `subtree' for WHICH); with prefix
argument, promote just the current heading (from a Lisp program, pass
nil for WHICH, or do not pass any argument)."
(interactive
(list (if (and transient-mark-mode mark-active) 'region
(outline-back-to-heading)
(if current-prefix-arg nil 'subtree))))
(cond
((eq which 'region)
(outline-map-region 'outline-promote (region-beginning) (region-end)))
(which
(outline-map-region 'outline-promote
(point)
(save-excursion (outline-get-next-sibling) (point))))
(t
(outline-back-to-heading t)
(let* ((head (match-string-no-properties 0))
(level (save-match-data (funcall outline-level)))
(up-head (or (outline-head-from-level (1- level) head)
(save-excursion
(save-match-data
(outline-up-heading 1 t)
(and (= (1- level) (funcall outline-level))
(match-string-no-properties 0))))
(outline-invent-heading head 'up))))
(unless (rassoc level outline-heading-alist)
(push (cons head level) outline-heading-alist))
(replace-match up-head nil t)))))
(defun outline-demote (&optional which)
"Demote headings lower down the tree.
If transient-mark-mode is on, and mark is active, demote headings in
the region (from a Lisp program, pass `region' for WHICH). Otherwise:
without prefix argument, demote current heading and all headings in the
subtree (from a Lisp program, pass `subtree' for WHICH); with prefix
argument, demote just the current heading (from a Lisp program, pass
nil for WHICH, or do not pass any argument)."
(interactive
(list (if (and transient-mark-mode mark-active) 'region
(outline-back-to-heading)
(if current-prefix-arg nil 'subtree))))
(cond
((eq which 'region)
(outline-map-region 'outline-demote (region-beginning) (region-end)))
(which
(outline-map-region 'outline-demote
(point)
(save-excursion (outline-get-next-sibling) (point))))
(t
(let* ((head (match-string-no-properties 0))
(level (save-match-data (funcall outline-level)))
(down-head
(or (outline-head-from-level (1+ level) head)
(save-excursion
(save-match-data
(while (and (progn (outline-next-heading) (not (eobp)))
(<= (funcall outline-level) level)))
(when (eobp)
(goto-char (point-min))
(while (and (progn (outline-next-heading) (not (eobp)))
(<= (funcall outline-level) level))))
(unless (eobp)
(looking-at outline-regexp)
(match-string-no-properties 0))))
(outline-invent-heading head nil))))
(unless (rassoc level outline-heading-alist)
(push (cons head level) outline-heading-alist))
(replace-match down-head nil t)))))
(defun outline-head-from-level (level head &optional alist)
"Get new heading with level LEVEL from ALIST.
If there are no such entries, return nil.
ALIST defaults to `outline-heading-alist'.
Similar to (car (rassoc LEVEL ALIST)).
If there are several different entries with same new level, choose
the one with the smallest distance to the assocation of HEAD in the alist.
This makes it possible for promotion to work in modes with several
independent sets of headings (numbered, unnumbered, appendix...)"
(unless alist (setq alist outline-heading-alist))
(let ((l (rassoc level alist))
ll h hl l2 l2l)
(cond
((null l) nil)
((null (setq h (assoc head (setq ll (memq l alist))))) (car l))
((null (setq l2 (rassoc level (cdr ll)))) (car l))
((memq h (setq l2l (memq l2 (cdr ll))))
(outline-head-from-level level head l2l))
((memq h (memq nil ll))
(outline-head-from-level level head l2l))
((memq l2 (memq nil (setq hl (memq h ll)))) (car l))
((< (* 2 (length hl)) (+ (length ll) (length l2l)))
(outline-head-from-level level head l2l))
(t (car l)))))
(defun outline-map-region (fun beg end)
"Call FUN for every heading between BEG and END.
When FUN is called, point is at the beginning of the heading and
the match data is set appropriately."
(save-excursion
(setq end (copy-marker end))
(goto-char beg)
(when (re-search-forward (concat "^\\(?:" outline-regexp "\\)") end t)
(goto-char (match-beginning 0))
(funcall fun)
(while (and (progn
(outline-next-heading)
(< (point) end))
(not (eobp)))
(funcall fun)))))
(defun outline-move-subtree-up (&optional arg)
"Move the currrent subtree up past ARG headlines of the same level."
(interactive "p")
(outline-move-subtree-down (- arg)))
(defun outline-move-subtree-down (&optional arg)
"Move the currrent subtree down past ARG headlines of the same level."
(interactive "p")
(let ((movfunc (if (> arg 0) 'outline-get-next-sibling
'outline-get-last-sibling))
(ins-point (make-marker))
(cnt (abs arg))
beg end folded)
(outline-back-to-heading)
(setq beg (point))
(save-match-data
(save-excursion (outline-end-of-heading)
(setq folded (outline-invisible-p)))
(outline-end-of-subtree))
(if (= (char-after) ?\n) (forward-char 1))
(setq end (point))
(goto-char beg)
(while (> cnt 0)
(or (funcall movfunc)
(progn (goto-char beg)
(error "Cannot move past superior level")))
(setq cnt (1- cnt)))
(if (> arg 0)
(progn (outline-end-of-subtree)
(if (= (char-after) ?\n) (forward-char 1))))
(move-marker ins-point (point))
(insert (delete-and-extract-region beg end))
(goto-char ins-point)
(if folded (hide-subtree))
(move-marker ins-point nil)))
(defun outline-end-of-heading ()
(if (re-search-forward outline-heading-end-regexp nil 'move)
(forward-char -1)))
(defun outline-next-visible-heading (arg)
"Move to the next visible heading line.
With argument, repeats or can move backward if negative.
A heading line is one that starts with a `*' (or that
`outline-regexp' matches)."
(interactive "p")
(if (< arg 0)
(beginning-of-line)
(end-of-line))
(let (found-heading-p)
(while (and (not (bobp)) (< arg 0))
(while (and (not (bobp))
(setq found-heading-p
(re-search-backward
(concat "^\\(?:" outline-regexp "\\)")
nil 'move))
(outline-invisible-p)))
(setq arg (1+ arg)))
(while (and (not (eobp)) (> arg 0))
(while (and (not (eobp))
(setq found-heading-p
(re-search-forward
(concat "^\\(?:" outline-regexp "\\)")
nil 'move))
(outline-invisible-p (match-beginning 0))))
(setq arg (1- arg)))
(if found-heading-p (beginning-of-line))))
(defun outline-previous-visible-heading (arg)
"Move to the previous heading line.
With argument, repeats or can move forward if negative.
A heading line is one that starts with a `*' (or that
`outline-regexp' matches)."
(interactive "p")
(outline-next-visible-heading (- arg)))
(defun outline-mark-subtree ()
"Mark the current subtree in an outlined document.
This puts point at the start of the current subtree, and mark at the end."
(interactive)
(let ((beg))
(if (outline-on-heading-p)
(beginning-of-line)
(outline-previous-visible-heading 1))
(setq beg (point))
(outline-end-of-subtree)
(push-mark (point) nil t)
(goto-char beg)))
(defvar outline-isearch-open-invisible-function nil
"Function called if `isearch' finishes in an invisible overlay.
The function is called with the overlay as its only argument.
If nil, `show-entry' is called to reveal the invisible text.")
(put 'outline 'reveal-toggle-invisible 'outline-reveal-toggle-invisible)
(defun outline-flag-region (from to flag)
"Hide or show lines from FROM to TO, according to FLAG.
If FLAG is nil then text is shown, while if FLAG is t the text is hidden."
(remove-overlays from to 'invisible 'outline)
(when flag
(let ((o (make-overlay from to)))
(overlay-put o 'invisible 'outline)
(overlay-put o 'isearch-open-invisible
(or outline-isearch-open-invisible-function
'outline-isearch-open-invisible))))
(run-hooks 'outline-view-change-hook))
(defun outline-reveal-toggle-invisible (o hidep)
(save-excursion
(goto-char (overlay-start o))
(if hidep
(progn
(let ((end (overlay-end o)))
(delete-overlay o)
(while (progn
(hide-subtree)
(outline-next-visible-heading 1)
(and (not (eobp)) (< (point) end))))))
(let ((o1 (copy-overlay o)))
(overlay-put o 'invisible nil) (while (progn
(show-entry)
(show-children)
(and (equal (overlay-start o) (overlay-start o1))
(< (point) (overlay-end o))
(= 0 (forward-line 1)))))
(when (equal (overlay-start o) (overlay-start o1))
(delete-overlay o1))))))
(defun outline-isearch-open-invisible (overlay)
(show-entry))
(defun hide-entry ()
"Hide the body directly following this heading."
(interactive)
(save-excursion
(outline-back-to-heading)
(outline-end-of-heading)
(outline-flag-region (point) (progn (outline-next-preface) (point)) t)))
(defun show-entry ()
"Show the body directly following this heading.
Show the heading too, if it is currently invisible."
(interactive)
(save-excursion
(outline-back-to-heading t)
(outline-flag-region (1- (point))
(progn (outline-next-preface) (point)) nil)))
(defun hide-body ()
"Hide all body lines in buffer, leaving all headings visible."
(interactive)
(hide-region-body (point-min) (point-max)))
(defun hide-region-body (start end)
"Hide all body lines in the region, but not headings."
(let (outline-view-change-hook)
(save-excursion
(save-restriction
(narrow-to-region start end)
(goto-char (point-min))
(if (outline-on-heading-p)
(outline-end-of-heading)
(outline-next-preface))
(while (not (eobp))
(outline-flag-region (point)
(progn (outline-next-preface) (point)) t)
(unless (eobp)
(forward-char (if (looking-at "\n\n") 2 1))
(outline-end-of-heading))))))
(run-hooks 'outline-view-change-hook))
(defun show-all ()
"Show all of the text in the buffer."
(interactive)
(outline-flag-region (point-min) (point-max) nil))
(defun hide-subtree ()
"Hide everything after this heading at deeper levels."
(interactive)
(outline-flag-subtree t))
(defun hide-leaves ()
"Hide the body after this heading and at deeper levels."
(interactive)
(save-excursion
(outline-back-to-heading)
(hide-region-body (point) (progn (outline-end-of-subtree) (point)))))
(defun show-subtree ()
"Show everything after this heading at deeper levels."
(interactive)
(outline-flag-subtree nil))
(defun outline-show-heading ()
"Show the current heading and move to its end."
(outline-flag-region (- (point)
(if (bobp) 0
(if (and outline-blank-line
(eq (char-before (1- (point))) ?\n))
2 1)))
(progn (outline-end-of-heading) (point))
nil))
(defun hide-sublevels (levels)
"Hide everything but the top LEVELS levels of headers, in whole buffer."
(interactive (list
(cond
(current-prefix-arg (prefix-numeric-value current-prefix-arg))
((save-excursion (beginning-of-line)
(looking-at outline-regexp))
(funcall outline-level))
(t 1))))
(if (< levels 1)
(error "Must keep at least one level of headers"))
(save-excursion
(let* (outline-view-change-hook
(beg (progn
(goto-char (point-min))
(unless (outline-on-heading-p t) (outline-next-heading))
(point)))
(end (progn
(goto-char (point-max))
(if (bolp) (1- (point)) (point)))))
(outline-flag-region beg end t)
(outline-map-region
(lambda ()
(if (<= (funcall outline-level) levels)
(outline-show-heading)))
beg end)))
(run-hooks 'outline-view-change-hook))
(defun hide-other ()
"Hide everything except current body and parent and top-level headings."
(interactive)
(hide-sublevels 1)
(let (outline-view-change-hook)
(save-excursion
(outline-back-to-heading t)
(show-entry)
(while (condition-case nil (progn (outline-up-heading 1 t) (not (bobp)))
(error nil))
(outline-flag-region (1- (point))
(save-excursion (forward-line 1) (point))
nil))))
(run-hooks 'outline-view-change-hook))
(defun outline-toggle-children ()
"Show or hide the current subtree depending on its current state."
(interactive)
(save-excursion
(outline-back-to-heading)
(if (not (outline-invisible-p (line-end-position)))
(hide-subtree)
(show-children)
(show-entry))))
(defun outline-flag-subtree (flag)
(save-excursion
(outline-back-to-heading)
(outline-end-of-heading)
(outline-flag-region (point)
(progn (outline-end-of-subtree) (point))
flag)))
(defun outline-end-of-subtree ()
(outline-back-to-heading)
(let ((first t)
(level (funcall outline-level)))
(while (and (not (eobp))
(or first (> (funcall outline-level) level)))
(setq first nil)
(outline-next-heading))
(if (and (bolp) (not (eolp)))
(progn
(forward-char -1)
(if (and outline-blank-line (bolp))
(forward-char -1))))))
(defun show-branches ()
"Show all subheadings of this heading, but not their bodies."
(interactive)
(show-children 1000))
(defun show-children (&optional level)
"Show all direct subheadings of this heading.
Prefix arg LEVEL is how many levels below the current level should be shown.
Default is enough to cause the following heading to appear."
(interactive "P")
(setq level
(if level (prefix-numeric-value level)
(save-excursion
(outline-back-to-heading)
(let ((start-level (funcall outline-level)))
(outline-next-heading)
(if (eobp)
1
(max 1 (- (funcall outline-level) start-level)))))))
(let (outline-view-change-hook)
(save-excursion
(outline-back-to-heading)
(setq level (+ level (funcall outline-level)))
(outline-map-region
(lambda ()
(if (<= (funcall outline-level) level)
(outline-show-heading)))
(point)
(progn (outline-end-of-subtree)
(if (eobp) (point-max) (1+ (point)))))))
(run-hooks 'outline-view-change-hook))
(defun outline-up-heading (arg &optional invisible-ok)
"Move to the visible heading line of which the present line is a subheading.
With argument, move up ARG levels.
If INVISIBLE-OK is non-nil, also consider invisible lines."
(interactive "p")
(and (eq this-command 'outline-up-heading)
(or (eq last-command 'outline-up-heading) (push-mark)))
(outline-back-to-heading invisible-ok)
(let ((start-level (funcall outline-level)))
(if (eq start-level 1)
(error "Already at top level of the outline"))
(while (and (> start-level 1) (> arg 0) (not (bobp)))
(let ((level start-level))
(while (not (or (< level start-level) (bobp)))
(if invisible-ok
(outline-previous-heading)
(outline-previous-visible-heading 1))
(setq level (funcall outline-level)))
(setq start-level level))
(setq arg (- arg 1))))
(looking-at outline-regexp))
(defun outline-forward-same-level (arg)
"Move forward to the ARG'th subheading at same level as this one.
Stop at the first and last subheadings of a superior heading."
(interactive "p")
(outline-back-to-heading)
(while (> arg 0)
(let ((point-to-move-to (save-excursion
(outline-get-next-sibling))))
(if point-to-move-to
(progn
(goto-char point-to-move-to)
(setq arg (1- arg)))
(progn
(setq arg 0)
(error "No following same-level heading"))))))
(defun outline-get-next-sibling ()
"Move to next heading of the same level, and return point.
If there is no such heading, return nil."
(let ((level (funcall outline-level)))
(outline-next-visible-heading 1)
(while (and (not (eobp)) (> (funcall outline-level) level))
(outline-next-visible-heading 1))
(if (or (eobp) (< (funcall outline-level) level))
nil
(point))))
(defun outline-backward-same-level (arg)
"Move backward to the ARG'th subheading at same level as this one.
Stop at the first and last subheadings of a superior heading."
(interactive "p")
(outline-back-to-heading)
(while (> arg 0)
(let ((point-to-move-to (save-excursion
(outline-get-last-sibling))))
(if point-to-move-to
(progn
(goto-char point-to-move-to)
(setq arg (1- arg)))
(progn
(setq arg 0)
(error "No previous same-level heading"))))))
(defun outline-get-last-sibling ()
"Move to previous heading of the same level, and return point.
If there is no such heading, return nil."
(let ((opoint (point))
(level (funcall outline-level)))
(outline-previous-visible-heading 1)
(when (and (/= (point) opoint) (outline-on-heading-p))
(while (and (> (funcall outline-level) level)
(not (bobp)))
(outline-previous-visible-heading 1))
(if (< (funcall outline-level) level)
nil
(point)))))
(defun outline-headers-as-kill (beg end)
"Save the visible outline headers in region at the start of the kill ring.
Text shown between the headers isn't copied. Two newlines are
inserted between saved headers. Yanking the result may be a
convenient way to make a table of contents of the buffer."
(interactive "r")
(save-excursion
(save-restriction
(narrow-to-region beg end)
(goto-char (point-min))
(let ((buffer (current-buffer))
start end)
(with-temp-buffer
(with-current-buffer buffer
(when (outline-on-heading-p)
(outline-back-to-heading)
(setq start (point)
end (progn (outline-end-of-heading)
(point)))
(insert-buffer-substring buffer start end)
(insert "\n\n")))
(let ((temp-buffer (current-buffer)))
(with-current-buffer buffer
(while (outline-next-heading)
(unless (outline-invisible-p)
(setq start (point)
end (progn (outline-end-of-heading) (point)))
(with-current-buffer temp-buffer
(insert-buffer-substring buffer start end)
(insert "\n\n"))))))
(kill-new (buffer-string)))))))
(provide 'outline)
(provide 'noutline)