-;;; Change Log:
-;;;
-;;; $Log: hide-ifdef-mode.el,v $
-;;; Revision 1.7 88/02/16 03:12:58 liberte
-;;; Fixed comments and doc strings.
-;;; Added optional prefix arg for ifdef motion commands.
-;;;
-;;; Revision 1.6 88/02/05 00:36:18 liberte
-;;; Bug fixes.
-;;; 1. A multi-line comment that starts on an #ifdef line
-;;; now ends on that line.
-;;; 2. Fix bad function name: hide-hif-ifdef-toggle-read-only
-;;; 3. Make ifdef-block hiding work outside of ifdefs.
-;;;
-;;; Revision 1.5 88/01/31 23:19:31 liberte
-;;; Major clean up.
-;;; Prefix internal names with "hif-".
-;;;
-;;; Revision 1.4 88/01/30 14:09:38 liberte
-;;; Add hide-ifdef-hiding and hide-ifdef-mode to minor-mode-alist.
-;;;
-;;; Revision 1.3 88/01/29 00:38:19 liberte
-;;; Fix three bugs.
-;;; 1. Function "defined" is just like lookup.
-;;; 2. Skip to newline or cr in case text is hidden.
-;;; 3. Use car of token list if just one symbol.
-;;;
-;;; Revision 1.2 88/01/28 23:32:46 liberte
-;;; Use hide-ifdef-mode-prefix-key.
-;;; Copy current-local-map so other buffers do not get
-;;; hide-ifdef-mode bindings.
-;;;
+;;; Commentary:
+
+;; To initialize, toggle the hide-ifdef minor mode with
+;;
+;; M-x hide-ifdef-mode
+;;
+;; This will set up key bindings and call hide-ifdef-mode-hook if it
+;; has a value. To explicitly hide ifdefs using a buffer-local
+;; define list (default empty), type
+;;
+;; M-x hide-ifdefs or C-c @ h
+;;
+;; Hide-ifdef suppresses the display of code that the preprocessor wouldn't
+;; pass through. The support of constant expressions in #if lines is
+;; limited to identifiers, parens, and the operators: &&, ||, !, and
+;; "defined". Please extend this.
+;;
+;; The hidden code is marked by ellipses (...). Be
+;; cautious when editing near ellipses, since the hidden text is
+;; still in the buffer, and you can move the point into it and modify
+;; text unawares.
+;; You can make your buffer read-only while hide-ifdef-hiding by setting
+;; hide-ifdef-read-only to a non-nil value. You can toggle this
+;; variable with hide-ifdef-toggle-read-only (C-c @ C-q).
+;;
+;; You can undo the effect of hide-ifdefs by typing
+;;
+;; M-x show-ifdefs or C-c @ s
+;;
+;; Use M-x hide-ifdef-define (C-c @ d) to define a symbol.
+;; Use M-x hide-ifdef-undef (C-c @ u) to undefine a symbol.
+;;
+;; If you define or undefine a symbol while hide-ifdef-mode is in effect,
+;; the display will be updated. Only the define list for the current
+;; buffer will be affected. You can save changes to the local define
+;; list with hide-ifdef-set-define-alist. This adds entries
+;; to hide-ifdef-define-alist.
+;;
+;; If you have defined a hide-ifdef-mode-hook, you can set
+;; up a list of symbols that may be used by hide-ifdefs as in the
+;; following example:
+;;
+;; (add-hook 'hide-ifdef-mode-hook
+;; (lambda ()
+;; (unless hide-ifdef-define-alist
+;; (setq hide-ifdef-define-alist
+;; '((list1 ONE TWO)
+;; (list2 TWO THREE))))
+;; (hide-ifdef-use-define-alist 'list2))) ; use list2 by default
+;;
+;; You can call hide-ifdef-use-define-alist (C-c @ U) at any time to specify
+;; another list to use.
+;;
+;; To cause ifdefs to be hidden as soon as hide-ifdef-mode is called,
+;; set hide-ifdef-initially to non-nil.
+;;
+;; If you set hide-ifdef-lines to t, hide-ifdefs hides all the #ifdef lines.
+;; In the absence of highlighting, that might be a bad idea. If you set
+;; hide-ifdef-lines to nil (the default), the surrounding preprocessor
+;; lines will be displayed. That can be confusing in its own
+;; right. Other variations on display are possible, but not much
+;; better.
+;;
+;; You can explicitly hide or show individual ifdef blocks irrespective
+;; of the define list by using hide-ifdef-block and show-ifdef-block.
+;;
+;; You can move the point between ifdefs with forward-ifdef, backward-ifdef,
+;; up-ifdef, down-ifdef, next-ifdef, and previous-ifdef.
+;;
+;; If you have minor-mode-alist in your mode line (the default) two labels
+;; may appear. "Ifdef" will appear when hide-ifdef-mode is active. "Hiding"
+;; will appear when text may be hidden ("hide-ifdef-hiding" is non-nil).
+;;
+;; Written by Brian Marick, at Gould, Computer Systems Division, Urbana IL.
+;; Extensively modified by Daniel LaLiberte (while at Gould).
+;;
+;; You may freely modify and distribute this, but keep a record
+;; of modifications and send comments to:
+;; liberte@a.cs.uiuc.edu or ihnp4!uiucdcs!liberte
+;; I will continue to upgrade hide-ifdef-mode
+;; with your contributions.