# HG changeset patch
# User Augie Fackler <durin42@gmail.com>
# Date 1228365241 21600
# Node ID d4d720c4c416ad53430d0061ba3bbb06b1dfa52b
# Parent  9b9098bda69193223e856b449003a85149021764
Add mercurial support to emacs. Improve setting of PYTHONPATH in there.

diff --git a/.elisp/mercurial.el b/.elisp/mercurial.el
new file mode 100644
--- /dev/null
+++ b/.elisp/mercurial.el
@@ -0,0 +1,1293 @@
+;;; mercurial.el --- Emacs support for the Mercurial distributed SCM
+
+;; Copyright (C) 2005, 2006 Bryan O'Sullivan
+
+;; Author: Bryan O'Sullivan <bos@serpentine.com>
+
+;; mercurial.el is free software; you can redistribute it and/or
+;; modify it under the terms of version 2 of the GNU General Public
+;; License as published by the Free Software Foundation.
+
+;; mercurial.el is distributed in the hope that it will be useful, but
+;; WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+;; General Public License for more details.
+
+;; You should have received a copy of the GNU General Public License
+;; along with mercurial.el, GNU Emacs, or XEmacs; see the file COPYING
+;; (`C-h C-l').  If not, write to the Free Software Foundation, Inc.,
+;; 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+;;; Commentary:
+
+;; mercurial.el builds upon Emacs's VC mode to provide flexible
+;; integration with the Mercurial distributed SCM tool.
+
+;; To get going as quickly as possible, load mercurial.el into Emacs and
+;; type `C-c h h'; this runs hg-help-overview, which prints a helpful
+;; usage overview.
+
+;; Much of the inspiration for mercurial.el comes from Rajesh
+;; Vaidheeswarran's excellent p4.el, which does an admirably thorough
+;; job for the commercial Perforce SCM product.  In fact, substantial
+;; chunks of code are adapted from p4.el.
+
+;; This code has been developed under XEmacs 21.5, and may not work as
+;; well under GNU Emacs (albeit tested under 21.4).  Patches to
+;; enhance the portability of this code, fix bugs, and add features
+;; are most welcome.
+
+;; As of version 22.3, GNU Emacs's VC mode has direct support for
+;; Mercurial, so this package may not prove as useful there.
+
+;; Please send problem reports and suggestions to bos@serpentine.com.
+
+
+;;; Code:
+
+(eval-when-compile (require 'cl))
+(require 'diff-mode)
+(require 'easymenu)
+(require 'executable)
+(require 'vc)
+
+(defmacro hg-feature-cond (&rest clauses)
+  "Test CLAUSES for feature at compile time.
+Each clause is (FEATURE BODY...)."
+  (dolist (x clauses)
+    (let ((feature (car x))
+	  (body (cdr x)))
+      (when (or (eq feature t)
+		(featurep feature))
+	(return (cons 'progn body))))))
+
+
+;;; XEmacs has view-less, while GNU Emacs has view.  Joy.
+
+(hg-feature-cond
+ (xemacs (require 'view-less))
+ (t (require 'view)))
+
+
+;;; Variables accessible through the custom system.
+
+(defgroup mercurial nil
+  "Mercurial distributed SCM."
+  :group 'tools)
+
+(defcustom hg-binary
+    (or (executable-find "hg")
+	(dolist (path '("~/bin/hg" "/usr/bin/hg" "/usr/local/bin/hg"))
+	  (when (file-executable-p path)
+	    (return path))))
+  "The path to Mercurial's hg executable."
+  :type '(file :must-match t)
+  :group 'mercurial)
+
+(defcustom hg-mode-hook nil
+  "Hook run when a buffer enters hg-mode."
+  :type 'sexp
+  :group 'mercurial)
+
+(defcustom hg-commit-mode-hook nil
+  "Hook run when a buffer is created to prepare a commit."
+  :type 'sexp
+  :group 'mercurial)
+
+(defcustom hg-pre-commit-hook nil
+  "Hook run before a commit is performed.
+If you want to prevent the commit from proceeding, raise an error."
+  :type 'sexp
+  :group 'mercurial)
+
+(defcustom hg-log-mode-hook nil
+  "Hook run after a buffer is filled with log information."
+  :type 'sexp
+  :group 'mercurial)
+
+(defcustom hg-global-prefix "\C-ch"
+  "The global prefix for Mercurial keymap bindings."
+  :type 'sexp
+  :group 'mercurial)
+
+(defcustom hg-commit-allow-empty-message nil
+  "Whether to allow changes to be committed with empty descriptions."
+  :type 'boolean
+  :group 'mercurial)
+
+(defcustom hg-commit-allow-empty-file-list nil
+  "Whether to allow changes to be committed without any modified files."
+  :type 'boolean
+  :group 'mercurial)
+
+(defcustom hg-rev-completion-limit 100
+  "The maximum number of revisions that hg-read-rev will offer to complete.
+This affects memory usage and performance when prompting for revisions
+in a repository with a lot of history."
+  :type 'integer
+  :group 'mercurial)
+
+(defcustom hg-log-limit 50
+  "The maximum number of revisions that hg-log will display."
+  :type 'integer
+  :group 'mercurial)
+
+(defcustom hg-update-modeline t
+  "Whether to update the modeline with the status of a file after every save.
+Set this to nil on platforms with poor process management, such as Windows."
+  :type 'boolean
+  :group 'mercurial)
+
+(defcustom hg-incoming-repository "default"
+  "The repository from which changes are pulled from by default.
+This should be a symbolic repository name, since it is used for all
+repository-related commands."
+  :type 'string
+  :group 'mercurial)
+
+(defcustom hg-outgoing-repository "default-push"
+  "The repository to which changes are pushed to by default.
+This should be a symbolic repository name, since it is used for all
+repository-related commands."
+  :type 'string
+  :group 'mercurial)
+
+
+;;; Other variables.
+
+(defvar hg-mode nil
+  "Is this file managed by Mercurial?")
+(make-variable-buffer-local 'hg-mode)
+(put 'hg-mode 'permanent-local t)
+
+(defvar hg-status nil)
+(make-variable-buffer-local 'hg-status)
+(put 'hg-status 'permanent-local t)
+
+(defvar hg-prev-buffer nil)
+(make-variable-buffer-local 'hg-prev-buffer)
+(put 'hg-prev-buffer 'permanent-local t)
+
+(defvar hg-root nil)
+(make-variable-buffer-local 'hg-root)
+(put 'hg-root 'permanent-local t)
+
+(defvar hg-view-mode nil)
+(make-variable-buffer-local 'hg-view-mode)
+(put 'hg-view-mode 'permanent-local t)
+
+(defvar hg-view-file-name nil)
+(make-variable-buffer-local 'hg-view-file-name)
+(put 'hg-view-file-name 'permanent-local t)
+
+(defvar hg-output-buffer-name "*Hg*"
+  "The name to use for Mercurial output buffers.")
+
+(defvar hg-file-history nil)
+(defvar hg-repo-history nil)
+(defvar hg-rev-history nil)
+(defvar hg-repo-completion-table nil)	; shut up warnings
+
+
+;;; Random constants.
+
+(defconst hg-commit-message-start
+  "--- Enter your commit message.  Type `C-c C-c' to commit. ---\n")
+
+(defconst hg-commit-message-end
+  "--- Files in bold will be committed.  Click to toggle selection. ---\n")
+
+(defconst hg-state-alist
+  '((?M . modified)
+    (?A . added)
+    (?R . removed)
+    (?! . deleted)
+    (?C . normal)
+    (?I . ignored)
+    (?? . nil)))
+
+;;; hg-mode keymap.
+
+(defvar hg-prefix-map
+  (let ((map (make-sparse-keymap)))
+    (hg-feature-cond (xemacs (set-keymap-name map 'hg-prefix-map))) ; XEmacs
+    (set-keymap-parent map vc-prefix-map)
+    (define-key map "=" 'hg-diff)
+    (define-key map "c" 'hg-undo)
+    (define-key map "g" 'hg-annotate)
+    (define-key map "i" 'hg-add)
+    (define-key map "l" 'hg-log)
+    (define-key map "n" 'hg-commit-start)
+    ;; (define-key map "r" 'hg-update)
+    (define-key map "u" 'hg-revert-buffer)
+    (define-key map "~" 'hg-version-other-window)
+    map)
+  "This keymap overrides some default vc-mode bindings.")
+
+(defvar hg-mode-map
+  (let ((map (make-sparse-keymap)))
+    (define-key map "\C-xv" hg-prefix-map)
+    map))
+
+(add-minor-mode 'hg-mode 'hg-mode hg-mode-map)
+
+
+;;; Global keymap.
+
+(defvar hg-global-map
+  (let ((map (make-sparse-keymap)))
+    (define-key map "," 'hg-incoming)
+    (define-key map "." 'hg-outgoing)
+    (define-key map "<" 'hg-pull)
+    (define-key map "=" 'hg-diff-repo)
+    (define-key map ">" 'hg-push)
+    (define-key map "?" 'hg-help-overview)
+    (define-key map "A" 'hg-addremove)
+    (define-key map "U" 'hg-revert)
+    (define-key map "a" 'hg-add)
+    (define-key map "c" 'hg-commit-start)
+    (define-key map "f" 'hg-forget)
+    (define-key map "h" 'hg-help-overview)
+    (define-key map "i" 'hg-init)
+    (define-key map "l" 'hg-log-repo)
+    (define-key map "r" 'hg-root)
+    (define-key map "s" 'hg-status)
+    (define-key map "u" 'hg-update)
+    map))
+
+(global-set-key hg-global-prefix hg-global-map)
+
+;;; View mode keymap.
+
+(defvar hg-view-mode-map
+  (let ((map (make-sparse-keymap)))
+    (hg-feature-cond (xemacs (set-keymap-name map 'hg-view-mode-map))) ; XEmacs
+    (define-key map (hg-feature-cond (xemacs [button2])
+				     (t [mouse-2]))
+      'hg-buffer-mouse-clicked)
+    map))
+
+(add-minor-mode 'hg-view-mode "" hg-view-mode-map)
+
+
+;;; Commit mode keymaps.
+
+(defvar hg-commit-mode-map
+  (let ((map (make-sparse-keymap)))
+    (define-key map "\C-c\C-c" 'hg-commit-finish)
+    (define-key map "\C-c\C-k" 'hg-commit-kill)
+    (define-key map "\C-xv=" 'hg-diff-repo)
+    map))
+
+(defvar hg-commit-mode-file-map
+  (let ((map (make-sparse-keymap)))
+    (define-key map (hg-feature-cond (xemacs [button2])
+				     (t [mouse-2]))
+      'hg-commit-mouse-clicked)
+    (define-key map " " 'hg-commit-toggle-file)
+    (define-key map "\r" 'hg-commit-toggle-file)
+    map))
+
+
+;;; Convenience functions.
+
+(defsubst hg-binary ()
+  (if hg-binary
+      hg-binary
+    (error "No `hg' executable found!")))
+
+(defsubst hg-replace-in-string (str regexp newtext &optional literal)
+  "Replace all matches in STR for REGEXP with NEWTEXT string.
+Return the new string.  Optional LITERAL non-nil means do a literal
+replacement.
+
+This function bridges yet another pointless impedance gap between
+XEmacs and GNU Emacs."
+  (hg-feature-cond
+   (xemacs (replace-in-string str regexp newtext literal))
+   (t (replace-regexp-in-string regexp newtext str nil literal))))
+
+(defsubst hg-strip (str)
+  "Strip leading and trailing blank lines from a string."
+  (hg-replace-in-string (hg-replace-in-string str "[\r\n][ \t\r\n]*\\'" "")
+			"\\`[ \t\r\n]*[\r\n]" ""))
+
+(defsubst hg-chomp (str)
+  "Strip trailing newlines from a string."
+  (hg-replace-in-string str "[\r\n]+\\'" ""))
+
+(defun hg-run-command (command &rest args)
+  "Run the shell command COMMAND, returning (EXIT-CODE . COMMAND-OUTPUT).
+The list ARGS contains a list of arguments to pass to the command."
+  (let* (exit-code
+	 (output
+	  (with-output-to-string
+	    (with-current-buffer
+		standard-output
+	      (setq exit-code
+		    (apply 'call-process command nil t nil args))))))
+    (cons exit-code output)))
+
+(defun hg-run (command &rest args)
+  "Run the Mercurial command COMMAND, returning (EXIT-CODE . COMMAND-OUTPUT)."
+  (apply 'hg-run-command (hg-binary) command args))
+
+(defun hg-run0 (command &rest args)
+  "Run the Mercurial command COMMAND, returning its output.
+If the command does not exit with a zero status code, raise an error."
+  (let ((res (apply 'hg-run-command (hg-binary) command args)))
+    (if (not (eq (car res) 0))
+	(error "Mercurial command failed %s - exit code %s"
+	       (cons command args)
+	       (car res))
+      (cdr res))))
+
+(defmacro hg-do-across-repo (path &rest body)
+  (let ((root-name (make-symbol "root-"))
+	(buf-name (make-symbol "buf-")))
+    `(let ((,root-name (hg-root ,path)))
+       (save-excursion
+	 (dolist (,buf-name (buffer-list))
+	   (set-buffer ,buf-name)
+	   (when (and hg-status (equal (hg-root buffer-file-name) ,root-name))
+	     ,@body))))))
+
+(put 'hg-do-across-repo 'lisp-indent-function 1)
+
+(defun hg-sync-buffers (path)
+  "Sync buffers visiting PATH with their on-disk copies.
+If PATH is not being visited, but is under the repository root, sync
+all buffers visiting files in the repository."
+  (let ((buf (find-buffer-visiting path)))
+    (if buf
+	(with-current-buffer buf
+	  (vc-buffer-sync))
+      (hg-do-across-repo path
+	(vc-buffer-sync)))))
+
+(defun hg-buffer-commands (pnt)
+  "Use the properties of a character to do something sensible."
+  (interactive "d")
+  (let ((rev (get-char-property pnt 'rev))
+	(file (get-char-property pnt 'file)))
+    (cond
+     (file
+      (find-file-other-window file))
+     (rev
+      (hg-diff hg-view-file-name rev rev))
+     ((message "I don't know how to do that yet")))))
+
+(defsubst hg-event-point (event)
+  "Return the character position of the mouse event EVENT."
+  (hg-feature-cond (xemacs (event-point event))
+		   (t (posn-point (event-start event)))))
+
+(defsubst hg-event-window (event)
+  "Return the window over which mouse event EVENT occurred."
+  (hg-feature-cond (xemacs (event-window event))
+		   (t (posn-window (event-start event)))))
+
+(defun hg-buffer-mouse-clicked (event)
+  "Translate the mouse clicks in a HG log buffer to character events.
+These are then handed off to `hg-buffer-commands'.
+
+Handle frickin' frackin' gratuitous event-related incompatibilities."
+  (interactive "e")
+  (select-window (hg-event-window event))
+  (hg-buffer-commands (hg-event-point event)))
+
+(defsubst hg-abbrev-file-name (file)
+  "Portable wrapper around abbreviate-file-name."
+  (hg-feature-cond (xemacs (abbreviate-file-name file t))
+		   (t (abbreviate-file-name file))))
+
+(defun hg-read-file-name (&optional prompt default)
+  "Read a file or directory name, or a pattern, to use with a command."
+  (save-excursion
+    (while hg-prev-buffer
+      (set-buffer hg-prev-buffer))
+    (let ((path (or default
+                    (buffer-file-name)
+                    (expand-file-name default-directory))))
+      (if (or (not path) current-prefix-arg)
+          (expand-file-name
+           (eval (list* 'read-file-name
+                        (format "File, directory or pattern%s: "
+                                (or prompt ""))
+                        (and path (file-name-directory path))
+                        nil nil
+                        (and path (file-name-nondirectory path))
+                        (hg-feature-cond
+			 (xemacs (cons (quote 'hg-file-history) nil))
+			 (t nil)))))
+        path))))
+
+(defun hg-read-number (&optional prompt default)
+  "Read a integer value."
+  (save-excursion
+    (if (or (not default) current-prefix-arg)
+        (string-to-number
+         (eval (list* 'read-string
+                      (or prompt "")
+                      (if default (cons (format "%d" default) nil) nil))))
+      default)))
+
+(defun hg-read-config ()
+  "Return an alist of (key . value) pairs of Mercurial config data.
+Each key is of the form (section . name)."
+  (let (items)
+    (dolist (line (split-string (hg-chomp (hg-run0 "debugconfig")) "\n") items)
+      (string-match "^\\([^=]*\\)=\\(.*\\)" line)
+      (let* ((left (substring line (match-beginning 1) (match-end 1)))
+	     (right (substring line (match-beginning 2) (match-end 2)))
+	     (key (split-string left "\\."))
+	     (value (hg-replace-in-string right "\\\\n" "\n" t)))
+	(setq items (cons (cons (cons (car key) (cadr key)) value) items))))))
+
+(defun hg-config-section (section config)
+  "Return an alist of (name . value) pairs for SECTION of CONFIG."
+  (let (items)
+    (dolist (item config items)
+      (when (equal (caar item) section)
+	(setq items (cons (cons (cdar item) (cdr item)) items))))))
+
+(defun hg-string-starts-with (sub str)
+  "Indicate whether string STR starts with the substring or character SUB."
+  (if (not (stringp sub))
+      (and (> (length str) 0) (equal (elt str 0) sub))
+    (let ((sub-len (length sub)))
+      (and (<= sub-len (length str))
+	   (string= sub (substring str 0 sub-len))))))
+
+(defun hg-complete-repo (string predicate all)
+  "Attempt to complete a repository name.
+We complete on either symbolic names from Mercurial's config or real
+directory names from the file system.  We do not penalise URLs."
+  (or (if all
+	  (all-completions string hg-repo-completion-table predicate)
+	(try-completion string hg-repo-completion-table predicate))
+      (let* ((str (expand-file-name string))
+	     (dir (file-name-directory str))
+	     (file (file-name-nondirectory str)))
+	(if all
+	    (let (completions)
+	      (dolist (name (delete "./" (file-name-all-completions file dir))
+			    completions)
+		(let ((path (concat dir name)))
+		  (when (file-directory-p path)
+		    (setq completions (cons name completions))))))
+	  (let ((comp (file-name-completion file dir)))
+	    (if comp
+		(hg-abbrev-file-name (concat dir comp))))))))
+
+(defun hg-read-repo-name (&optional prompt initial-contents default)
+  "Read the location of a repository."
+  (save-excursion
+    (while hg-prev-buffer
+      (set-buffer hg-prev-buffer))
+    (let (hg-repo-completion-table)
+      (if current-prefix-arg
+	  (progn
+	    (dolist (path (hg-config-section "paths" (hg-read-config)))
+	      (setq hg-repo-completion-table
+		    (cons (cons (car path) t) hg-repo-completion-table))
+	      (unless (hg-string-starts-with (hg-feature-cond
+					      (xemacs directory-sep-char)
+					      (t ?/))
+					     (cdr path))
+		(setq hg-repo-completion-table
+		      (cons (cons (cdr path) t) hg-repo-completion-table))))
+	    (completing-read (format "Repository%s: " (or prompt ""))
+			     'hg-complete-repo
+			     nil
+			     nil
+			     initial-contents
+			     'hg-repo-history
+			     default))
+	default))))
+
+(defun hg-read-rev (&optional prompt default)
+  "Read a revision or tag, offering completions."
+  (save-excursion
+    (while hg-prev-buffer
+      (set-buffer hg-prev-buffer))
+    (let ((rev (or default "tip")))
+      (if current-prefix-arg
+	  (let ((revs (split-string
+		       (hg-chomp
+			(hg-run0 "-q" "log" "-l"
+				 (format "%d" hg-rev-completion-limit)))
+		       "[\n:]")))
+	    (dolist (line (split-string (hg-chomp (hg-run0 "tags")) "\n"))
+	      (setq revs (cons (car (split-string line "\\s-")) revs)))
+	    (completing-read (format "Revision%s (%s): "
+				     (or prompt "")
+				     (or default "tip"))
+			     (mapcar (lambda (x) (cons x x)) revs)
+			     nil
+			     nil
+			     nil
+			     'hg-rev-history
+			     (or default "tip")))
+	rev))))
+
+(defun hg-parents-for-mode-line (root)
+  "Format the parents of the working directory for the mode line."
+  (let ((parents (split-string (hg-chomp
+				(hg-run0 "--cwd" root "parents" "--template"
+					 "{rev}\n")) "\n")))
+    (mapconcat 'identity parents "+")))
+
+(defun hg-buffers-visiting-repo (&optional path)
+  "Return a list of buffers visiting the repository containing PATH."
+  (let ((root-name (hg-root (or path (buffer-file-name))))
+	bufs)
+    (save-excursion
+      (dolist (buf (buffer-list) bufs)
+	(set-buffer buf)
+	(let ((name (buffer-file-name)))
+	  (when (and hg-status name (equal (hg-root name) root-name))
+	    (setq bufs (cons buf bufs))))))))
+
+(defun hg-update-mode-lines (path)
+  "Update the mode lines of all buffers visiting the same repository as PATH."
+  (let* ((root (hg-root path))
+	 (parents (hg-parents-for-mode-line root)))
+    (save-excursion
+      (dolist (info (hg-path-status
+		     root
+		     (mapcar
+		      (function
+		       (lambda (buf)
+			 (substring (buffer-file-name buf) (length root))))
+		      (hg-buffers-visiting-repo root))))
+	(let* ((name (car info))
+	       (status (cdr info))
+	       (buf (find-buffer-visiting (concat root name))))
+	  (when buf
+	    (set-buffer buf)
+	    (hg-mode-line-internal status parents)))))))
+
+
+;;; View mode bits.
+
+(defun hg-exit-view-mode (buf)
+  "Exit from hg-view-mode.
+We delete the current window if entering hg-view-mode split the
+current frame."
+  (when (and (eq buf (current-buffer))
+	     (> (length (window-list)) 1))
+    (delete-window))
+  (when (buffer-live-p buf)
+    (kill-buffer buf)))
+
+(defun hg-view-mode (prev-buffer &optional file-name)
+  (goto-char (point-min))
+  (set-buffer-modified-p nil)
+  (toggle-read-only t)
+  (hg-feature-cond (xemacs (view-minor-mode prev-buffer 'hg-exit-view-mode))
+		   (t (view-mode-enter nil 'hg-exit-view-mode)))
+  (setq hg-view-mode t)
+  (setq truncate-lines t)
+  (when file-name
+    (setq hg-view-file-name
+	  (hg-abbrev-file-name file-name))))
+
+(defun hg-file-status (file)
+  "Return status of FILE, or nil if FILE does not exist or is unmanaged."
+  (let* ((s (hg-run "status" file))
+	 (exit (car s))
+	 (output (cdr s)))
+    (if (= exit 0)
+	(let ((state (and (>= (length output) 2)
+			  (= (aref output 1) ? )
+			  (assq (aref output 0) hg-state-alist))))
+	  (if state
+	      (cdr state)
+	    'normal)))))
+
+(defun hg-path-status (root paths)
+  "Return status of PATHS in repo ROOT as an alist.
+Each entry is a pair (FILE-NAME . STATUS)."
+  (let ((s (apply 'hg-run "--cwd" root "status" "-marduc" paths))
+	result)
+    (dolist (entry (split-string (hg-chomp (cdr s)) "\n") (nreverse result))
+      (let (state name)
+	(cond ((= (aref entry 1) ? )
+	       (setq state (assq (aref entry 0) hg-state-alist)
+		     name (substring entry 2)))
+	      ((string-match "\\(.*\\): " entry)
+	       (setq name (match-string 1 entry))))
+	(setq result (cons (cons name state) result))))))
+
+(defmacro hg-view-output (args &rest body)
+  "Execute BODY in a clean buffer, then quickly display that buffer.
+If the buffer contains one line, its contents are displayed in the
+minibuffer.  Otherwise, the buffer is displayed in view-mode.
+ARGS is of the form (BUFFER-NAME &optional FILE), where BUFFER-NAME is
+the name of the buffer to create, and FILE is the name of the file
+being viewed."
+  (let ((prev-buf (make-symbol "prev-buf-"))
+	(v-b-name (car args))
+	(v-m-rest (cdr args)))
+    `(let ((view-buf-name ,v-b-name)
+	   (,prev-buf (current-buffer)))
+       (get-buffer-create view-buf-name)
+       (kill-buffer view-buf-name)
+       (get-buffer-create view-buf-name)
+       (set-buffer view-buf-name)
+       (save-excursion
+	 ,@body)
+       (case (count-lines (point-min) (point-max))
+	 ((0)
+	  (kill-buffer view-buf-name)
+	  (message "(No output)"))
+	 ((1)
+	  (let ((msg (hg-chomp (buffer-substring (point-min) (point-max)))))
+	    (kill-buffer view-buf-name)
+	    (message "%s" msg)))
+	 (t
+	  (pop-to-buffer view-buf-name)
+	  (setq hg-prev-buffer ,prev-buf)
+	  (hg-view-mode ,prev-buf ,@v-m-rest))))))
+
+(put 'hg-view-output 'lisp-indent-function 1)
+
+;;; Context save and restore across revert and other operations.
+
+(defun hg-position-context (pos)
+  "Return information to help find the given position again."
+  (let* ((end (min (point-max) (+ pos 98))))
+    (list pos
+	  (buffer-substring (max (point-min) (- pos 2)) end)
+	  (- end pos))))
+
+(defun hg-buffer-context ()
+  "Return information to help restore a user's editing context.
+This is useful across reverts and merges, where a context is likely
+to have moved a little, but not really changed."
+  (let ((point-context (hg-position-context (point)))
+	(mark-context (let ((mark (mark-marker)))
+			(and mark
+			     ;; make sure active mark
+			     (marker-buffer mark)
+			     (marker-position mark)
+			     (hg-position-context mark)))))
+    (list point-context mark-context)))
+
+(defun hg-find-context (ctx)
+  "Attempt to find a context in the given buffer.
+Always returns a valid, hopefully sane, position."
+  (let ((pos (nth 0 ctx))
+	(str (nth 1 ctx))
+	(fixup (nth 2 ctx)))
+    (save-excursion
+      (goto-char (max (point-min) (- pos 15000)))
+      (if (and (not (equal str ""))
+	       (search-forward str nil t))
+	  (- (point) fixup)
+	(max pos (point-min))))))
+
+(defun hg-restore-context (ctx)
+  "Attempt to restore the user's editing context."
+  (let ((point-context (nth 0 ctx))
+	(mark-context (nth 1 ctx)))
+    (goto-char (hg-find-context point-context))
+    (when mark-context
+      (set-mark (hg-find-context mark-context)))))
+
+
+;;; Hooks.
+
+(defun hg-mode-line-internal (status parents)
+  (setq hg-status status
+	hg-mode (and status (concat " Hg:"
+				    parents
+				    (cdr (assq status
+					       '((normal . "")
+						 (removed . "r")
+						 (added . "a")
+						 (deleted . "!")
+						 (modified . "m"))))))))
+
+(defun hg-mode-line (&optional force)
+  "Update the modeline with the current status of a file.
+An update occurs if optional argument FORCE is non-nil,
+hg-update-modeline is non-nil, or we have not yet checked the state of
+the file."
+  (let ((root (hg-root)))
+    (when (and root (or force hg-update-modeline (not hg-mode)))
+      (let ((status (hg-file-status buffer-file-name))
+	    (parents (hg-parents-for-mode-line root)))
+	(hg-mode-line-internal status parents)
+	status))))
+
+(defun hg-mode (&optional toggle)
+  "Minor mode for Mercurial distributed SCM integration.
+
+The Mercurial mode user interface is based on that of VC mode, so if
+you're already familiar with VC, the same keybindings and functions
+will generally work.
+
+Below is a list of many common SCM tasks.  In the list, `G/L\'
+indicates whether a key binding is global (G) to a repository or
+local (L) to a file.  Many commands take a prefix argument.
+
+SCM Task                              G/L  Key Binding  Command Name
+--------                              ---  -----------  ------------
+Help overview (what you are reading)  G    C-c h h      hg-help-overview
+
+Tell Mercurial to manage a file       G    C-c h a      hg-add
+Commit changes to current file only   L    C-x v n      hg-commit-start
+Undo changes to file since commit     L    C-x v u      hg-revert-buffer
+
+Diff file vs last checkin             L    C-x v =      hg-diff
+
+View file change history              L    C-x v l      hg-log
+View annotated file                   L    C-x v a      hg-annotate
+
+Diff repo vs last checkin             G    C-c h =      hg-diff-repo
+View status of files in repo          G    C-c h s      hg-status
+Commit all changes                    G    C-c h c      hg-commit-start
+
+Undo all changes since last commit    G    C-c h U      hg-revert
+View repo change history              G    C-c h l      hg-log-repo
+
+See changes that can be pulled        G    C-c h ,      hg-incoming
+Pull changes                          G    C-c h <      hg-pull
+Update working directory after pull   G    C-c h u      hg-update
+See changes that can be pushed        G    C-c h .      hg-outgoing
+Push changes                          G    C-c h >      hg-push"
+  (unless vc-make-backup-files
+    (set (make-local-variable 'backup-inhibited) t))
+  (run-hooks 'hg-mode-hook))
+
+(defun hg-find-file-hook ()
+  (ignore-errors
+    (when (hg-mode-line)
+      (hg-mode))))
+
+(add-hook 'find-file-hooks 'hg-find-file-hook)
+
+(defun hg-after-save-hook ()
+  (ignore-errors
+    (let ((old-status hg-status))
+      (hg-mode-line)
+      (if (and (not old-status) hg-status)
+	  (hg-mode)))))
+
+(add-hook 'after-save-hook 'hg-after-save-hook)
+
+
+;;; User interface functions.
+
+(defun hg-help-overview ()
+  "This is an overview of the Mercurial SCM mode for Emacs.
+
+You can find the source code, license (GPL v2), and credits for this
+code by typing `M-x find-library mercurial RET'."
+  (interactive)
+  (hg-view-output ("Mercurial Help Overview")
+    (insert (documentation 'hg-help-overview))
+    (let ((pos (point)))
+      (insert (documentation 'hg-mode))
+      (goto-char pos)
+      (end-of-line 1)
+      (delete-region pos (point)))
+    (let ((hg-root-dir (hg-root)))
+      (if (not hg-root-dir)
+	  (error "error: %s: directory is not part of a Mercurial repository."
+		 default-directory)
+	(cd hg-root-dir)))))
+
+(defun hg-fix-paths ()
+  "Fix paths reported by some Mercurial commands."
+  (save-excursion
+    (goto-char (point-min))
+    (while (re-search-forward " \\.\\.." nil t)
+      (replace-match " " nil nil))))
+
+(defun hg-add (path)
+  "Add PATH to the Mercurial repository on the next commit.
+With a prefix argument, prompt for the path to add."
+  (interactive (list (hg-read-file-name " to add")))
+  (let ((buf (current-buffer))
+	(update (equal buffer-file-name path)))
+    (hg-view-output (hg-output-buffer-name)
+      (apply 'call-process (hg-binary) nil t nil (list "add" path))
+      (hg-fix-paths)
+      (goto-char (point-min))
+      (cd (hg-root path)))
+    (when update
+      (unless vc-make-backup-files
+	(set (make-local-variable 'backup-inhibited) t))
+      (with-current-buffer buf
+	(hg-mode-line)))))
+
+(defun hg-addremove ()
+  (interactive)
+  (error "not implemented"))
+
+(defun hg-annotate ()
+  (interactive)
+  (error "not implemented"))
+
+(defun hg-commit-toggle-file (pos)
+  "Toggle whether or not the file at POS will be committed."
+  (interactive "d")
+  (save-excursion
+    (goto-char pos)
+    (let ((face (get-text-property pos 'face))
+	  (inhibit-read-only t)
+	  bol)
+      (beginning-of-line)
+      (setq bol (+ (point) 4))
+      (end-of-line)
+      (if (eq face 'bold)
+	  (progn
+	    (remove-text-properties bol (point) '(face nil))
+	    (message "%s will not be committed"
+		     (buffer-substring bol (point))))
+	(add-text-properties bol (point) '(face bold))
+	(message "%s will be committed"
+		 (buffer-substring bol (point)))))))
+
+(defun hg-commit-mouse-clicked (event)
+  "Toggle whether or not the file at POS will be committed."
+  (interactive "@e")
+  (hg-commit-toggle-file (hg-event-point event)))
+
+(defun hg-commit-kill ()
+  "Kill the commit currently being prepared."
+  (interactive)
+  (when (or (not (buffer-modified-p)) (y-or-n-p "Really kill this commit? "))
+    (let ((buf hg-prev-buffer))
+      (kill-buffer nil)
+      (switch-to-buffer buf))))
+
+(defun hg-commit-finish ()
+  "Finish preparing a commit, and perform the actual commit.
+The hook hg-pre-commit-hook is run before anything else is done.  If
+the commit message is empty and hg-commit-allow-empty-message is nil,
+an error is raised.  If the list of files to commit is empty and
+hg-commit-allow-empty-file-list is nil, an error is raised."
+  (interactive)
+  (let ((root hg-root))
+    (save-excursion
+      (run-hooks 'hg-pre-commit-hook)
+      (goto-char (point-min))
+      (search-forward hg-commit-message-start)
+      (let (message files)
+	(let ((start (point)))
+	  (goto-char (point-max))
+	  (search-backward hg-commit-message-end)
+	  (setq message (hg-strip (buffer-substring start (point)))))
+	(when (and (= (length message) 0)
+		   (not hg-commit-allow-empty-message))
+	  (error "Cannot proceed - commit message is empty"))
+	(forward-line 1)
+	(beginning-of-line)
+	(while (< (point) (point-max))
+	  (let ((pos (+ (point) 4)))
+	    (end-of-line)
+	    (when (eq (get-text-property pos 'face) 'bold)
+	      (end-of-line)
+	      (setq files (cons (buffer-substring pos (point)) files))))
+	  (forward-line 1))
+	(when (and (= (length files) 0)
+		   (not hg-commit-allow-empty-file-list))
+	  (error "Cannot proceed - no files to commit"))
+	(setq message (concat message "\n"))
+	(apply 'hg-run0 "--cwd" hg-root "commit" "-m" message files))
+      (let ((buf hg-prev-buffer))
+	(kill-buffer nil)
+	(switch-to-buffer buf))
+      (hg-update-mode-lines root))))
+
+(defun hg-commit-mode ()
+  "Mode for describing a commit of changes to a Mercurial repository.
+This involves two actions: describing the changes with a commit
+message, and choosing the files to commit.
+
+To describe the commit, simply type some text in the designated area.
+
+By default, all modified, added and removed files are selected for
+committing.  Files that will be committed are displayed in bold face\;
+those that will not are displayed in normal face.
+
+To toggle whether a file will be committed, move the cursor over a
+particular file and hit space or return.  Alternatively, middle click
+on the file.
+
+Key bindings
+------------
+\\[hg-commit-finish]		proceed with commit
+\\[hg-commit-kill]		kill commit
+
+\\[hg-diff-repo]		view diff of pending changes"
+  (interactive)
+  (use-local-map hg-commit-mode-map)
+  (set-syntax-table text-mode-syntax-table)
+  (setq local-abbrev-table text-mode-abbrev-table
+	major-mode 'hg-commit-mode
+	mode-name "Hg-Commit")
+  (set-buffer-modified-p nil)
+  (setq buffer-undo-list nil)
+  (run-hooks 'text-mode-hook 'hg-commit-mode-hook))
+
+(defun hg-commit-start ()
+  "Prepare a commit of changes to the repository containing the current file."
+  (interactive)
+  (while hg-prev-buffer
+    (set-buffer hg-prev-buffer))
+  (let ((root (hg-root))
+	(prev-buffer (current-buffer))
+	modified-files)
+    (unless root
+      (error "Cannot commit outside a repository!"))
+    (hg-sync-buffers root)
+    (setq modified-files (hg-chomp (hg-run0 "--cwd" root "status" "-arm")))
+    (when (and (= (length modified-files) 0)
+	       (not hg-commit-allow-empty-file-list))
+      (error "No pending changes to commit"))
+    (let* ((buf-name (format "*Mercurial: Commit %s*" root)))
+      (pop-to-buffer (get-buffer-create buf-name))
+      (when (= (point-min) (point-max))
+	(set (make-local-variable 'hg-root) root)
+	(setq hg-prev-buffer prev-buffer)
+	(insert "\n")
+	(let ((bol (point)))
+	  (insert hg-commit-message-end)
+	  (add-text-properties bol (point) '(face bold-italic)))
+	(let ((file-area (point)))
+	  (insert modified-files)
+	  (goto-char file-area)
+	  (while (< (point) (point-max))
+	    (let ((bol (point)))
+	      (forward-char 1)
+	      (insert "  ")
+	      (end-of-line)
+	      (add-text-properties (+ bol 4) (point)
+				   '(face bold mouse-face highlight)))
+	    (forward-line 1))
+	  (goto-char file-area)
+	  (add-text-properties (point) (point-max)
+			       `(keymap ,hg-commit-mode-file-map))
+	  (goto-char (point-min))
+	  (insert hg-commit-message-start)
+	  (add-text-properties (point-min) (point) '(face bold-italic))
+	  (insert "\n\n")
+	  (forward-line -1)
+	  (save-excursion
+	    (goto-char (point-max))
+	    (search-backward hg-commit-message-end)
+	    (add-text-properties (match-beginning 0) (point-max)
+				 '(read-only t))
+	    (goto-char (point-min))
+	    (search-forward hg-commit-message-start)
+	    (add-text-properties (match-beginning 0) (match-end 0)
+				 '(read-only t)))
+	  (hg-commit-mode)
+          (cd root))))))
+
+(defun hg-diff (path &optional rev1 rev2)
+  "Show the differences between REV1 and REV2 of PATH.
+When called interactively, the default behaviour is to treat REV1 as
+the \"parent\" revision, REV2 as the current edited version of the file, and
+PATH as the file edited in the current buffer.
+With a prefix argument, prompt for all of these."
+  (interactive (list (hg-read-file-name " to diff")
+                     (let ((rev1 (hg-read-rev " to start with" 'parent)))
+		       (and (not (eq rev1 'parent)) rev1))
+		     (let ((rev2 (hg-read-rev " to end with" 'working-dir)))
+		       (and (not (eq rev2 'working-dir)) rev2))))
+  (hg-sync-buffers path)
+  (let ((a-path (hg-abbrev-file-name path))
+        ;; none revision is specified explicitly
+        (none (and (not rev1) (not rev2)))
+        ;; only one revision is specified explicitly
+        (one (or (and (or (equal rev1 rev2) (not rev2)) rev1)
+                 (and (not rev1) rev2)))
+	diff)
+    (hg-view-output ((cond
+		      (none
+		       (format "Mercurial: Diff against parent of %s" a-path))
+		      (one
+		       (format "Mercurial: Diff of rev %s of %s" one a-path))
+		      (t
+		       (format "Mercurial: Diff from rev %s to %s of %s"
+			       rev1 rev2 a-path))))
+      (cond
+       (none
+        (call-process (hg-binary) nil t nil "diff" path))
+       (one
+        (call-process (hg-binary) nil t nil "diff" "-r" one path))
+       (t
+        (call-process (hg-binary) nil t nil "diff" "-r" rev1 "-r" rev2 path)))
+      (diff-mode)
+      (setq diff (not (= (point-min) (point-max))))
+      (font-lock-fontify-buffer)
+      (cd (hg-root path)))
+    diff))
+
+(defun hg-diff-repo (path &optional rev1 rev2)
+  "Show the differences between REV1 and REV2 of repository containing PATH.
+When called interactively, the default behaviour is to treat REV1 as
+the \"parent\" revision, REV2 as the current edited version of the file, and
+PATH as the `hg-root' of the current buffer.
+With a prefix argument, prompt for all of these."
+  (interactive (list (hg-read-file-name " to diff")
+                     (let ((rev1 (hg-read-rev " to start with" 'parent)))
+		       (and (not (eq rev1 'parent)) rev1))
+		     (let ((rev2 (hg-read-rev " to end with" 'working-dir)))
+		       (and (not (eq rev2 'working-dir)) rev2))))
+  (hg-diff (hg-root path) rev1 rev2))
+
+(defun hg-forget (path)
+  "Lose track of PATH, which has been added, but not yet committed.
+This will prevent the file from being incorporated into the Mercurial
+repository on the next commit.
+With a prefix argument, prompt for the path to forget."
+  (interactive (list (hg-read-file-name " to forget")))
+  (let ((buf (current-buffer))
+	(update (equal buffer-file-name path)))
+    (hg-view-output (hg-output-buffer-name)
+      (apply 'call-process (hg-binary) nil t nil (list "forget" path))
+      ;; "hg forget" shows pathes relative NOT TO ROOT BUT TO REPOSITORY
+      (hg-fix-paths)
+      (goto-char (point-min))
+      (cd (hg-root path)))
+    (when update
+      (with-current-buffer buf
+        (when (local-variable-p 'backup-inhibited)
+          (kill-local-variable 'backup-inhibited))
+	(hg-mode-line)))))
+
+(defun hg-incoming (&optional repo)
+  "Display changesets present in REPO that are not present locally."
+  (interactive (list (hg-read-repo-name " where changes would come from")))
+  (hg-view-output ((format "Mercurial: Incoming from %s to %s"
+			   (hg-abbrev-file-name (hg-root))
+			   (hg-abbrev-file-name
+			    (or repo hg-incoming-repository))))
+    (call-process (hg-binary) nil t nil "incoming"
+		  (or repo hg-incoming-repository))
+    (hg-log-mode)
+    (cd (hg-root))))
+
+(defun hg-init ()
+  (interactive)
+  (error "not implemented"))
+
+(defun hg-log-mode ()
+  "Mode for viewing a Mercurial change log."
+  (goto-char (point-min))
+  (when (looking-at "^searching for changes.*$")
+    (delete-region (match-beginning 0) (match-end 0)))
+  (run-hooks 'hg-log-mode-hook))
+
+(defun hg-log (path &optional rev1 rev2 log-limit)
+  "Display the revision history of PATH.
+History is displayed between REV1 and REV2.
+Number of displayed changesets is limited to LOG-LIMIT.
+REV1 defaults to the tip, while REV2 defaults to 0.
+LOG-LIMIT defaults to `hg-log-limit'.
+With a prefix argument, prompt for each parameter."
+  (interactive (list (hg-read-file-name " to log")
+                     (hg-read-rev " to start with"
+                                  "tip")
+                     (hg-read-rev " to end with"
+				  "0")
+                     (hg-read-number "Output limited to: "
+                                     hg-log-limit)))
+  (let ((a-path (hg-abbrev-file-name path))
+        (r1 (or rev1 "tip"))
+        (r2 (or rev2 "0"))
+        (limit (format "%d" (or log-limit hg-log-limit))))
+    (hg-view-output ((if (equal r1 r2)
+                         (format "Mercurial: Log of rev %s of %s" rev1 a-path)
+                       (format
+                        "Mercurial: at most %s log(s) from rev %s to %s of %s"
+                        limit r1 r2 a-path)))
+      (eval (list* 'call-process (hg-binary) nil t nil
+                   "log"
+                   "-r" (format "%s:%s" r1 r2)
+                   "-l" limit
+                   (if (> (length path) (length (hg-root path)))
+                       (cons path nil)
+                     nil)))
+      (hg-log-mode)
+      (cd (hg-root path)))))
+
+(defun hg-log-repo (path &optional rev1 rev2 log-limit)
+  "Display the revision history of the repository containing PATH.
+History is displayed between REV1 and REV2.
+Number of displayed changesets is limited to LOG-LIMIT,
+REV1 defaults to the tip, while REV2 defaults to 0.
+LOG-LIMIT defaults to `hg-log-limit'.
+With a prefix argument, prompt for each parameter."
+  (interactive (list (hg-read-file-name " to log")
+                     (hg-read-rev " to start with"
+                                  "tip")
+                     (hg-read-rev " to end with"
+				  "0")
+                     (hg-read-number "Output limited to: "
+                                     hg-log-limit)))
+  (hg-log (hg-root path) rev1 rev2 log-limit))
+
+(defun hg-outgoing (&optional repo)
+  "Display changesets present locally that are not present in REPO."
+  (interactive (list (hg-read-repo-name " where changes would go to" nil
+					hg-outgoing-repository)))
+  (hg-view-output ((format "Mercurial: Outgoing from %s to %s"
+			   (hg-abbrev-file-name (hg-root))
+			   (hg-abbrev-file-name
+			    (or repo hg-outgoing-repository))))
+    (call-process (hg-binary) nil t nil "outgoing"
+		  (or repo hg-outgoing-repository))
+    (hg-log-mode)
+    (cd (hg-root))))
+
+(defun hg-pull (&optional repo)
+  "Pull changes from repository REPO.
+This does not update the working directory."
+  (interactive (list (hg-read-repo-name " to pull from")))
+  (hg-view-output ((format "Mercurial: Pull to %s from %s"
+			   (hg-abbrev-file-name (hg-root))
+			   (hg-abbrev-file-name
+			    (or repo hg-incoming-repository))))
+    (call-process (hg-binary) nil t nil "pull"
+		  (or repo hg-incoming-repository))
+    (cd (hg-root))))
+
+(defun hg-push (&optional repo)
+  "Push changes to repository REPO."
+  (interactive (list (hg-read-repo-name " to push to")))
+  (hg-view-output ((format "Mercurial: Push from %s to %s"
+			   (hg-abbrev-file-name (hg-root))
+			   (hg-abbrev-file-name
+			    (or repo hg-outgoing-repository))))
+    (call-process (hg-binary) nil t nil "push"
+		  (or repo hg-outgoing-repository))
+    (cd (hg-root))))
+
+(defun hg-revert-buffer-internal ()
+  (let ((ctx (hg-buffer-context)))
+    (message "Reverting %s..." buffer-file-name)
+    (hg-run0 "revert" buffer-file-name)
+    (revert-buffer t t t)
+    (hg-restore-context ctx)
+    (hg-mode-line)
+    (message "Reverting %s...done" buffer-file-name)))
+
+(defun hg-revert-buffer ()
+  "Revert current buffer's file back to the latest committed version.
+If the file has not changed, nothing happens.  Otherwise, this
+displays a diff and asks for confirmation before reverting."
+  (interactive)
+  (let ((vc-suppress-confirm nil)
+	(obuf (current-buffer))
+	diff)
+    (vc-buffer-sync)
+    (unwind-protect
+	(setq diff (hg-diff buffer-file-name))
+      (when diff
+	(unless (yes-or-no-p "Discard changes? ")
+	  (error "Revert cancelled")))
+      (when diff
+	(let ((buf (current-buffer)))
+	  (delete-window (selected-window))
+	  (kill-buffer buf))))
+    (set-buffer obuf)
+    (when diff
+      (hg-revert-buffer-internal))))
+
+(defun hg-root (&optional path)
+  "Return the root of the repository that contains the given path.
+If the path is outside a repository, return nil.
+When called interactively, the root is printed.  A prefix argument
+prompts for a path to check."
+  (interactive (list (hg-read-file-name)))
+  (if (or path (not hg-root))
+      (let ((root (do ((prev nil dir)
+		       (dir (file-name-directory
+                             (or
+                              path
+                              buffer-file-name
+                              (expand-file-name default-directory)))
+			    (file-name-directory (directory-file-name dir))))
+		      ((equal prev dir))
+		    (when (file-directory-p (concat dir ".hg"))
+		      (return dir)))))
+	(when (interactive-p)
+	  (if root
+	      (message "The root of this repository is `%s'." root)
+	    (message "The path `%s' is not in a Mercurial repository."
+		     (hg-abbrev-file-name path))))
+	root)
+    hg-root))
+
+(defun hg-cwd (&optional path)
+  "Return the current directory of PATH within the repository."
+  (do ((stack nil (cons (file-name-nondirectory
+			 (directory-file-name dir))
+			stack))
+       (prev nil dir)
+       (dir (file-name-directory (or path buffer-file-name
+				     (expand-file-name default-directory)))
+	    (file-name-directory (directory-file-name dir))))
+      ((equal prev dir))
+    (when (file-directory-p (concat dir ".hg"))
+      (let ((cwd (mapconcat 'identity stack "/")))
+	(unless (equal cwd "")
+	  (return (file-name-as-directory cwd)))))))
+
+(defun hg-status (path)
+  "Print revision control status of a file or directory.
+With prefix argument, prompt for the path to give status for.
+Names are displayed relative to the repository root."
+  (interactive (list (hg-read-file-name " for status" (hg-root))))
+  (let ((root (hg-root)))
+    (hg-view-output ((format "Mercurial: Status of %s in %s"
+			     (let ((name (substring (expand-file-name path)
+						    (length root))))
+			       (if (> (length name) 0)
+				   name
+				 "*"))
+			     (hg-abbrev-file-name root)))
+      (apply 'call-process (hg-binary) nil t nil
+	     (list "--cwd" root "status" path))
+      (cd (hg-root path)))))
+
+(defun hg-undo ()
+  (interactive)
+  (error "not implemented"))
+
+(defun hg-update ()
+  (interactive)
+  (error "not implemented"))
+
+(defun hg-version-other-window (rev)
+  "Visit version REV of the current file in another window.
+If the current file is named `F', the version is named `F.~REV~'.
+If `F.~REV~' already exists, use it instead of checking it out again."
+  (interactive "sVersion to visit (default is workfile version): ")
+  (let* ((file buffer-file-name)
+       	 (version (if (string-equal rev "")
+		       "tip"
+		        rev))
+ 	 (automatic-backup (vc-version-backup-file-name file version))
+          (manual-backup (vc-version-backup-file-name file version 'manual)))
+     (unless (file-exists-p manual-backup)
+       (if (file-exists-p automatic-backup)
+           (rename-file automatic-backup manual-backup nil)
+         (hg-run0 "-q" "cat" "-r" version "-o" manual-backup file)))
+     (find-file-other-window manual-backup)))
+
+
+(provide 'mercurial)
+
+
+;;; Local Variables:
+;;; prompt-to-byte-compile: nil
+;;; end:
diff --git a/.emacs b/.emacs
--- a/.emacs
+++ b/.emacs
@@ -13,6 +13,8 @@
 (require 'show-wspace)
 (require 'doctest-mode)
 
+(require 'mercurial)
+
 ; Clojure
 (require 'clojure-auto)
 (setq auto-mode-alist (cons '("\\.clj$" . clojure-mode) auto-mode-alist))
@@ -60,7 +62,9 @@ point."
 (add-hook 'python-mode-hook 'af-python-mode-hook)
 
 ;;pymacs
-(setenv "PYTHONPATH" (concat (getenv "HOME") "/unixSoft/lib/python"))
+(if (string-match "unixSoft/lib/python" (getenv "PATH"))
+    (setenv "PYTHONPATH" (concat (getenv "HOME") "/unixSoft/lib/python"))
+  )
 (autoload 'pymacs-apply "pymacs")
 (autoload 'pymacs-call "pymacs")
 (autoload 'pymacs-eval "pymacs" nil t)