anchor.diff:  (defun p/default-decl (input)
     ;; [60] DefaultDecl ::= '#REQUIRED' | '#IMPLIED'
     ;;                       | (('#FIXED' S)? AttValue) /* VC: Required Attribute */
  -  ;;                       
  +  ;;
     ;; /* VC: Attribute Default Legal */
     ;; /* WFC: No < in Attribute Values */
     ;; /* VC: Fixed Attribute Default */
     (multiple-value-bind (cat sem) (peek-token input)
  -    (cond ((eq cat :|#REQUIRED|) 
  +    (cond ((eq cat :|#REQUIRED|)
              (consume-token input) :REQUIRED)
  -          ((eq cat :|#IMPLIED|)  
  +          ((eq cat :|#IMPLIED|)
              (consume-token input) :IMPLIED)
             ((eq cat :|#FIXED|)
              (consume-token input)
  
positive.code: 
  (defun validate-attribute* (ctx adef value)
    (let ((type (attdef-type adef))
          (default (attdef-default adef))) 
      (when (and (listp default)
                 (eq (car default) :FIXED)
                 (not (rod= value (cadr default))))
  
negative.code: 
  (defun peek-token (input)
    (cond ((zstream-token-category input)
           (values
            (zstream-token-category input)
            (zstream-token-semantic input)))
          (t
  