anchor.diff:  
   (defmethod add-function-dynamic-extent (environment function-name)
     (make-instance 'function-dynamic-extent
  +    :next environment
       :name function-name))
   
   (defclass optimize (entry)
  
positive.code: 
  (defmethod add-inline (environment function-name inline)
    (make-instance 'inline
      :name function-name
      :inline inline))
  
negative.code: 
  (defmethod add-variable-ignore (environment symbol ignore)
    (make-instance 'variable-ignore
      :next environment
      :name symbol
      :ignore ignore))
  
  