Wouldn't Exception::getContext() be useful?

Right now the only way I know of to see the context of an exception throw is to pass it in.. throw new CustomException(get_definted_vars()); It would be very useful to have exceptions just have this as a method. set_error_handle had this ability, but it's now deprecated. I'm guessing there's an engine reason why this hasn't happened because it seems like a pretty obvious include to the default methods of the Exception and Error objects.