You did give enough information in this case, but errors in posted code frequently act as red herrings, where people trying to help get confused about what's actually at issue. As well, if posted code doesn't display exactly the errors reported, many potential helpers will skip your issue. Such an error can also be inadvertently copied into a suggested solution, resulting in difficulties. And finally, I have frequently found that the act of coming up with my example code to post tracks down exactly the issue I needed help with.