anchor.diff:  
   (defun read-frame-slot (frame slot)
     (memref-t (memref-unsigned-byte-64 (third frame) -1) (- (1+ slot))))
  +
  +(defun write-frame-slot (frame slot value)
  +  (setf (memref-t (memref-unsigned-byte-64 (third frame) -1) (- (1+ slot)))
  +        value))
   
   (defun show-debug-frame ()
     (format t "Frame ~D(~X): ~S~%"
  
positive.code:             (setf env-object (svref env-object 0)))))))
    (format t "Unknown variable id ~S." id))
  
  
  (defun enter-debugger (condition)
    (with-standard-io-syntax
  
negative.code:                             (dolist (v result)
                                (fresh-line)
                                (write v)))))
                         (:write
                          (let (slot value)
                            (format t "~&ID: ")
                            (finish-output)
                            (setf slot (read))
                            (format t "~&Value: ")
                            (finish-output)
                            (setf value (eval (read)))
                            (debugger-write-variable *current-debug-frame* slot value)))
                         (t (format t "Unknown command ~S~%" form))))
                      (t (let ((result (multiple-value-list (let ((- form))
                                                              (eval form)))))
  