-;(defun number-to-register (arg char)
-; "Store a number in a register.
-;Two args, NUMBER and REGISTER (a character, naming the register).
-;If NUMBER is nil, digits in the buffer following point are read
-;to get the number to store.
-;Interactively, NUMBER is the prefix arg (none means nil)."
-; (interactive "P\ncNumber to register: ")
-; (set-register char
-; (if arg
-; (prefix-numeric-value arg)
-; (if (looking-at "[0-9][0-9]*")
-; (save-excursion
-; (save-restriction
-; (narrow-to-region (point)
-; (progn (skip-chars-forward "0-9")
-; (point)))
-; (goto-char (point-min))
-; (read (current-buffer))))
-; 0))))
-
-;(defun increment-register (arg char)
-; "Add NUMBER to the contents of register REGISTER.
-;Interactively, NUMBER is the prefix arg (none means nil)."
-; (interactive "p\ncNumber to register: ")
-; (or (integerp (get-register char))
-; (error "Register does not contain a number"))
-; (set-register char (+ arg (get-register char))))
-
-(defun view-register (char)
+(defun register-swap-out ()
+ "Turn markers into file-query references when a buffer is killed."
+ (and buffer-file-name
+ (dolist (elem register-alist)
+ (and (markerp (cdr elem))
+ (eq (marker-buffer (cdr elem)) (current-buffer))
+ (setcdr elem
+ (list 'file-query
+ buffer-file-name
+ (marker-position (cdr elem))))))))
+
+(defun number-to-register (number register)
+ "Store a number in a register.
+Two args, NUMBER and REGISTER (a character, naming the register).
+If NUMBER is nil, a decimal number is read from the buffer starting
+at point, and point moves to the end of that number.
+Interactively, NUMBER is the prefix arg (none means nil)."
+ (interactive "P\ncNumber to register: ")
+ (set-register register
+ (if number
+ (prefix-numeric-value number)
+ (if (looking-at "\\s-*-?[0-9]+")
+ (progn
+ (goto-char (match-end 0))
+ (string-to-number (match-string 0)))
+ 0))))
+
+(defun increment-register (number register)
+ "Add NUMBER to the contents of register REGISTER.
+Interactively, NUMBER is the prefix arg."
+ (interactive "p\ncIncrement register: ")
+ (or (numberp (get-register register))
+ (error "Register does not contain a number"))
+ (set-register register (+ number (get-register register))))
+
+(defun view-register (register)