@justinbmeyer I am checking why exception is not shown in console. In the above case getting undefined array is a valid case and I was expecting expecting an array with at least 1 item. To avoid that I put undefined check.
I was also wondering how a unhandled exception messed up whole observe framework. Sometimes my assumption on data will be wrong and there will be unhandled undefined exceptions. In those cases I want to protect observe framework so that my whole application does not crash.