anchor.diff:              %% Unfurl up to the tag, then accumulate it
               [{T0, A0, [destack(Pre ++ [T]) | Acc0]} | Post]
       end.
  -    
  +
   destack([{Tag, Attrs, Acc}]) ->
       {Tag, Attrs, lists:reverse(Acc)};
   destack([{T1, A1, Acc1}, {T0, A0, Acc0} | Rest]) ->
  
positive.code: 
  tokenize_charref(Bin, S=#decoder{offset=O}) ->
      tokenize_charref(Bin, S, O).
      
  tokenize_charref(Bin, S=#decoder{offset=O}, Start) ->
      case Bin of
          <<_:O/binary>> ->
  
negative.code: -define(IS_LITERAL_SAFE(C),
          ((C >= $A andalso C =< $Z) orelse (C >= $a andalso C =< $z)
           orelse (C >= $0 andalso C =< $9))).
  
  -record(decoder, {line=1,
                    column=1,
                    offset=0}).
  