anchor.diff:  %%-spec(is_expr(Node:: syntaxTree())-> boolean()).
   is_expr(Node) ->
       As = refac_syntax:get_ann(Node),
  -    case lists:keysearch(category, 1, As) of
  -	{value, {category, C}} ->
  -	    case C of
  -		expression -> true;
  -		{_, _, expression} -> true;
  -		guard_expression -> true;
  -		application_op -> true;
  -		_ -> false
  -	    end;
  -	_ -> false
  -    end.
  -
  -is_expr_or_match(Node) ->
  -    is_expr(Node) 
  -	orelse 
  -	  (refac_syntax:type(Node)==match_expr andalso
  -	   lists:keysearch(category, 1, refac_syntax:get_ann(Node))==false).
  -  
  -    
  +    {category, expression} == lists:keyfind(category, 1, As) orelse 
  +        {category, guard_expression} == lists:keyfind(category, 1, As).
  +
    
   %% =====================================================================
   %% @doc Return true if an AST node represents a pattern.
   %%-spec(is_pattern(Node:: syntaxTree())-> boolean()).
  +
  +-spec(is_pattern(Node:: syntaxTree())-> boolean()).
   is_pattern(Node) ->
       As = refac_syntax:get_ann(Node),
  -    case lists:keysearch(category, 1, As) of
  -	{value, {category, pattern}} ->
  -	    true;
  -	{value, {category, {_, _, pattern}}} ->
  -	    true;
  -	_ -> false
  -    end.
  +    {category, pattern}==lists:keyfind(category, 1, As).
  +
   
   %%===============================================================================
   %% @spec is_exported({FunName::atom(), Arity::integer()},ModuleInfo) -> boolean()
  
positive.code: 	 format_search_paths/1,default_incls/0, get_toks/1,
           reset_attrs/1, reset_ann_and_pos/1, reset_ann/1,
  	 get_env_vars/1,get_var_exports/1,get_bound_vars/1,get_free_vars/1,
  	 is_expr/1,is_expr_or_match/1, is_pattern/1, is_exported/2, inscope_funs/1,update_ann/2,
  	 delete_from_ann/2, callback_funs/1, is_callback_fun/3, rewrite/2, rewrite_with_wrapper/2,
  	 get_range/1, max/2, min/2, modname_to_filename/2, funname_to_defpos/2,
    	 spawn_funs/0,is_spawn_app/1, get_start_end_loc_with_comment/1]).
  
negative.code:     F = fun (N, S) ->
  		case refac_syntax:type(N) of
  		    variable ->
  			Ann = refac_syntax:get_ann(N),
                          case lists:keysearch(syntax_path, 1, Ann) of
  			    {value, {syntax_path, macro_name}} -> S;
  			    _ ->
  				VarName = refac_syntax:variable_name(N),
  				ordsets:add_element(VarName, S)
  