anchor.diff:  format(Str, F, Node) ->
       Env = #env{node=Node,f=F},
       Str1 = case Str of [$\n|_] -> Str; _ -> [$\n|Str] end,
  -    format_txt(Str1, Env, [], Str1).
  +    {Env1, Txt} = format_txt(Str1, Env, [], Str1),
  +    Txt.
   
   blank_line(S=[$\n|_]) -> {yes, S};
   blank_line([$\t|T])   -> blank_line(T);
  
positive.code: after_nl([${,$\n|T], Env, L, Doc)  -> pre(T, Env, L, Doc);
  after_nl([${,${|T], Env, L, Doc)   -> emb(T, Env, L, Doc);
  after_nl([${|T], Env, L, Doc)      -> pre(T, Env, L, Doc);
  after_nl([$[|T], Env, L, Doc)      -> note(T, Env, L, Doc);
  after_nl("____" ++ T, Env, L, Doc) -> hr(T, Env, L, Doc);
  after_nl(S=[$-|T], Env, L, Doc)    -> mk_list(S, Env, L, Doc);
  
negative.code: %%
  %% Blocks (denoted by special characters in column 1):
  %%                      [              Note
  %%                        ...
  %%                      ]
  %%                      [expires:Date  expire tagged region
  %%                        ...
  %%                      ]
  %%                      {              Preformatted
  