 
 (defconst rdebug-traceback-line-re
   "^[ \t]+from \\([^:]+\\):\\([0-9]+\\)\\(in `.*'\\)?"
-  "Regular expression that describes tracebacks.")
+  "Regular expression that describes a Ruby traceback line.")
 
 (defun rdebug-rdebugtrack-overlay-arrow (activation)
   "Activate or de arrow at beginning-of-line in current buffer."

    (gud-def gud-where   "where"
	     "T" "Show stack trace.")
    (local-set-key "\C-i" 'gud-gdb-complete-command)
    (setq comint-prompt-regexp "^(rdb:-) ")
    (setq paragraph-start comint-prompt-regexp)
    
    ;; Update GUD menu bar
    (define-key gud-menu-map [args]      '("Show arguments of current stack" . 

  (interactive "d")
  (save-excursion
    (goto-char pt)
    (let ((s (concat "-->" (buffer-substring (point-at-bol) (point-at-eol)))))
      (when (string-match rdebug--stack-frame-regexp s)
        (let ((frame (substring s (match-beginning 2) (match-end 2))))
          (gud-call (concat "frame " frame)))))))
