anchor.diff:  
   (setf (item-at-1 *spanner-parsing-environments* 'default)
         `((,(create-scanner '(:sequence escaped-character)) escaped-character)
  -        
           (,(create-scanner '(:sequence inline-image)) inline-image)
           (,(create-scanner '(:sequence reference-image)) reference-image)
  -        
           ;; do early
           (,(create-scanner '(:sequence coded-reference-link)) code)
           (,(create-scanner '(:sequence inline-link)) inline-link)
           (,(create-scanner '(:sequence reference-link)) reference-link)
           (,(create-scanner '(:sequence backtick)) code)
  -
           (,(create-scanner '(:sequence strong-em-1)) strong-em)
           (,(create-scanner '(:sequence strong-em-2)) strong-em)
  -        
           (,(create-scanner '(:sequence strong-2)) strong)
           (,(create-scanner '(:sequence strong-1)) strong)
           (,(create-scanner '(:sequence emphasis-2)) emphasis)
  
positive.code:         (bind ((lines (slot-value chunk 'lines))
                 ((values scanners kind) (scanners-for-chunk chunk))
                 (*current-span* kind))
            (scan-lines-with-scanners lines scanners)
            #+(or)
            (loop for (regex name) in scanners do
                  (setf lines
                        (let ((result nil))
                          (iterate-elements
                           lines
                           (lambda (line) 
                             (setf result 
                                   (append result (scan-one-span line name regex)))))
                          result)))))
    chunk)
  
  ;;; ---------------------------------------------------------------------------
  
negative.code: ;;; ---------------------------------------------------------------------------
  
  (setf (item-at-1 *spanner-parsing-environments* '(code))
        `((,(create-scanner '(:sequence html)) html)
          (,(create-scanner '(:sequence entity)) entity) ;;?
  	))
  
  ;;; ---------------------------------------------------------------------------
  
  