anchor.diff:           (setf bol nil))
          (add-text parser token))
   
  -      ((and (indentation-p token) (>= (spaces token) (current-indentation parser)))
  +      ((indentation>= token (current-indentation parser))
          (setf extra-indentation (- (spaces token) (current-indentation parser))))
   
  -      ((and (indentation-p token) (< (spaces token) (current-indentation parser)))
  +      ((indentation< token (current-indentation parser))
          (decf (current-indentation parser) *verbatim-indentation*)
          (pop-frame-and-element verbatim)
          (process-token parser token)))))
  
positive.code: 
  (defun indentation-p (token) (typep token 'indentation))
  
  (defgeneric to-sexp (thing))
  
  (defmethod to-sexp ((string string)) string)
  
negative.code: (defun open-list-item (parser list-marker indentation)
    (let ((item (open-element parser "li")))
      (with-bindings (parser token)
        ((indentation< token indentation)
         (setf (current-indentation parser) (spaces token))
         (pop-frame-and-element item)
         (process-token parser token))
  