anchor.diff:      lists:map(fun
                     ({br})        -> "\n";
                     ({i, Inline}) -> [Inline]
  -                  %({l, Line})   -> ["<l>", Line, "</l>\n"];
  -                  %({i, Inline}) -> ["<i>", Inline, "</i>"]
                 end, format_content(Content, Ctx)).
   
   format_content(Content, Ctx) ->
  
positive.code:                    IndentedRest <- [prepend("    ", Rest)] ]);
  format_element(li, #xmlElement{}, Lines, _Ctx) ->
      [{li, Lines}];
  format_element(_, #xmlElement{name = Name} = E, Lines, Ctx) ->
      Lines.
  
  format_header(#xmlElement{name = Name, parents = Parents} = E, Lines, Ctx) ->
      %has_non_header_parents(E) andalso erlang:error({non_header_parents, Parents}, [E]),
      Headers = #{h1 => "# ",
                  h2 => "## ",
                  h3 => "### ",
  
negative.code: prepend( Prefix, [{br} | Doc], Acc) -> prepend(Prefix, Doc, [{br}, {i, Prefix} | Acc]);
  prepend( Prefix, [Node | Doc], Acc) -> prepend(Prefix, Doc, [Node | Acc]).
  
  enumerate(List) ->
      lists:zip(lists:seq(1, length(List)), List).
  
  