anchor.diff:  					{value, {pid, PidInfo}} = lists:keysearch(pid, 1, refac_syntax:get_ann(Node)),
   					case Arguments of 
   					    [FunExpr] -> 
  -						{PidInfo, {FunExpr, {ModName, Ln}}};   %%Question: what about if the FunExpr contains free variables?
  -					    [_N, FunExpr] -> {PidInfo, FunExpr};
  +						[{PidInfo, {FunExpr, {ModName, Ln}}, {FileName, Node}}];   %%Question: what about if the FunExpr contains free variables?
  +					    [_N, FunExpr] -> [{PidInfo, FunExpr,{FileName, Node}}];
   					    [M, F, A] -> 
   						case {refac_syntax:type(M), refac_syntax:type(F), refac_syntax:type(A)} of
   						    {atom, atom, list} ->
  -							{PidInfo, {refac_syntax:atom_value(M),   %%TODO: need to use backward slice
  +							[{PidInfo, {refac_syntax:atom_value(M),   %%TODO: need to use backward slice
   								   refac_syntax:atom_value(F), 
  -								   refac_syntax:list_length(A)}};    
  +								   refac_syntax:list_length(A)}, {FileName, Node}}];    
   						    _ -> io:format("\n*************************************Warning****************************************\n"),
  -							 io:format("Wrangler could not handle the spawn expression used in module ~p at line ~p\n", [ModName,Ln])
  +							 io:format("Wrangler could not handle the spawn expression used in module ~p at line ~p\n", [ModName,Ln]),
  +							 []
   						end;
   					    [_N, M, F, A] ->
   						case {refac_syntax:type(M), refac_syntax:type(F), refac_syntax:type(A)} of
   						    {atom, atom, list} ->
  -							{PidInfo, {refac_syntax:atom_value(M),   %%TODO: need to use backward slice
  +							[{PidInfo, {refac_syntax:atom_value(M),   %%TODO: need to use backward slice
   								   refac_syntax:atom_value(F), 
  -								   refac_syntax:list_length(A)}};    
  +								   refac_syntax:list_length(A)}, {FileName, Node}}];    
   						    _ -> io:format("\n*************************************Warning****************************************\n"),
  -							 io:format("Wrangler could not handle the spawn expression used in module ~p at line ~p\n", [ModName,Ln])
  +							 io:format("Wrangler could not handle the spawn expression used in module ~p at line ~p\n", [ModName,Ln]),
  +							 []
   						end
   					    end;
   				    _ ->
  
positive.code:       _ -> false
      end.
  
  
  
  %% Qn: is it possible to get more static infomration? How to balance the usages of staic and dynamic info?
  %% How do we know the existing trace info is uptodate?
  
negative.code: %% ============================================================================================
  %% Refactoring: Add a tag to all the messages received by a process.
  %%
  %% Copyright (C) 2006-2009  Huiqing Li, Simon Thompson
  
  %% The contents of this file are subject to the Erlang Public License,
  %% Version 1.1, (the "License"); you may not use this file except in
  