anchor.diff:    (minibuffer-start-charpos nil))
   
   (defun map-frame (key frame)
  -  (setf (gethash key *frame-display-map*) frame))
  +  (setf (gethash key *display-frame-map*) frame))
   
   (defun get-frame (key)
  -  (gethash key *frame-display-map*))
  +  (gethash key *display-frame-map*))
   
   (defun current-frame ()
     (get-frame (implementation)))
   
   (defun unmap-frame (key)
  -  (let ((frame (gethash key *frame-display-map*)))
  +  (let ((frame (gethash key *display-frame-map*)))
       (remhash key)
       frame))
   
  
positive.code: (in-package :lem)
  
  (defparameter *frame-display-map* (make-hash-table))
  
  (defstruct frame
    ;; window
  
negative.code:   (maphash (lambda (k v)
               (declare (ignore k))
               (teardown-frame v))
             *display-frame-map*))
  
  (defun redraw-frame (frame)
    (redraw-display* frame))
  