anchor.diff:  
   (defun clear-all-attribute-cache ()
     (dolist (attribute *attributes*)
  +    (when *attribute-destroy-%internal-value* ; let client clean up
  +      (funcall *attribute-destroy-%internal-value* attribute))
       (setf (get attribute '%attribute-value) nil)))
   
   (defun display-light-p ()
  
positive.code:           syntax-function-name-attribute
            syntax-variable-attribute
            syntax-type-attribute
            syntax-builtin-attribute))
  
  (defvar *attributes* '())
  
  
negative.code: 
  (define-attribute syntax-builtin-attribute
    (t :foreground "#D030F0"))
  
  