watch expressions with dbg.el

asdf.el

(defun dbg-watch (expression)
  (interactive "sExpression: ")
  (dbg-mi-command (list 'dbg-watch-handler expression) "-var-create - @ %s" (prin1-to-string expression)))

(defun dbg-watch-handler (status result expression)
  (case status
    ((done)
     (push (cons (cons 'expression expression) result) dbg-watches)))
  (dbg-render-watches))

(defun dbg-update-watches ()
  (dbg-mi-command 'dbg-update-watches-handler "-var-update --all-values *"))

(defun dbg-update-watches-handler (status result)
  (case status
    ((done)
     (dolist (change (dbg-item result 'changelist))
       (dolist (watch dbg-watches)
         (when (equal (dbg-item watch 'name) (dbg-item change 'name))
           (setf (dbg-item watch 'value) (dbg-item change 'value))
           (let ((type (dbg-item change 'type)))
             (when type
               (setf (dbg-item watch 'type) type))))))))
  (dbg-render-watches))

(defun dbg-render-watches ()
  (with-read-only-buffer dbg-watches-buffer
    (erase-buffer)
    (dolist (watch dbg-watches)
      (insert (format "%s\n" (dbg-expression-string watch))))))