anchor.diff:      erl_syntax:tuple(Vars).
   
   labels_to_underscores(Term) ->
  +    labels_to_underscores(Term, []).
  +
  +labels_to_underscores(Term, Except) ->
       erl_syntax_lib:map(
         fun(T) ->
                 try
                     Label = erl_syntax:atom_value(T),
                     true = is_label(Label),
  -                  erl_syntax:underscore()
  +		  case lists:member(Label, Except) of
  +		      true ->
  +			  label_to_var(Label);
  +		      false ->
  +			  erl_syntax:underscore()
  +		  end
                 catch _:_ ->
                         T
                 end
  
positive.code: 					  _ElsVar|CDataVars ++ NewElemVars("__TopXMLNS")
  					  ++ SubElVars ++ XmlElVars])])];
  			       false ->
  				   [erl_syntax:clause(
  				      [], IfGuard,
  				      [make_function_call(
  					 FunName,
  					 [erl_syntax:variable("__TopXMLNS"),
  					  erl_syntax:variable("__IgnoreEls"),
  					  _ElsVar|CDataVars ++ NewElemVars("_xmlns")
  					  ++ SubElVars ++ XmlElVars])])]
  			   end ++
  			       [erl_syntax:clause(
  				  [], none,
  				  [make_function_call(
  				     FunName,
  				     [erl_syntax:variable("__TopXMLNS"),
  
negative.code:                       XMLNSAttrs = if IgnoreXMLNS or HasXMLNSAttr
  				      or is_list(XMLNS) or IsDuplicated ->
                                             erl_syntax:list([]);
  				      true ->
                                             erl_syntax:list(
                                               [erl_syntax:tuple(
                                                  [abstract(<<"xmlns">>),
  