anchor.diff:     indentation element)
   
     (linkdef
  -   "[" (-> (text-until "]") name) "] <" (-> (text-until ">") url) ">"
  +   "[" (-> (text-until "]") name) "]" whitespace "<" (-> (text-until ">") url) ">"
      (or newline blank)
       `(:link_def (:link ,name) (:url ,url)))
   
  
positive.code:   (term
     indentation "% "
     (=> (many1 (or (text-until (or tag-open " %")) tagged-text)) `(:dt ,@_))
     " %" eol)
  
    (definition
     (=> (many1 (and indentation (! "% ") paragraph)) `(:dd ,@_)))
  
negative.code:    indentation
     (or header
         section
         section-divider
         verbatim
         ordered-list
         unordered-list
         definition-list
         blockquote
         linkdef
         paragraph))
  
    (header
  