anchor.diff:  			     {{N, RData}, <<>>} = protobuffs:decode(list_to_binary(Bin), Type),
       			 in_range(Data,Type) andalso
       			     FieldNum=:=N andalso
  -    			     (Data==RData orelse foreign_type(Type,Data,RData))  
  +    			     (compare(Data,RData) orelse foreign_type(Type,Data,RData))
   	     end).
   
   prop_encode_decode() ->
  
positive.code:     	    begin
          		{{N, RData}, <<>>} = protobuffs:decode(list_to_binary(protobuffs:encode(FieldNum, Data, Type)), Type),
          		FieldNum=:=N andalso 
          		(Data==RData orelse foreign_type(Type,Data,RData))  
      	    end
  	    )).
  
  
negative.code:     2;
  exp(N) ->
      2*exp(N-1).
  
  %%%%%%%%%%%%%%%%% Helper functions %%%%%%%%%%%%%%%%%%%%%%%%%%%%
  
  