anchor.diff:  (in-package :lem-base)
   
   (export '(fundamental-mode
  +          primordial-buffer
             current-buffer
             make-buffer
             buffer
  
positive.code: 
  (defvar *current-buffer*)
  
  (defun current-buffer ()
    "現在の`buffer`を返します。"
    (unless (boundp '*current-buffer*)
      (setf *current-buffer*
            (make-buffer +original-buffer-name+)))
    *current-buffer*)
  
  (defun (setf current-buffer) (buffer)
  
negative.code: (export '(%buffer-keep-binfo
            %buffer-clear-keep-binfo))
  
  (defparameter +primordial-buffer-name+ "*tmp*")
  
  (defclass buffer ()
    ((name
  