must be the last statement in the method. This means that you will have to put everything you want to do after the call to Binding.of_caller into the block of it. This should be no problem however, because Ruby has closures. If you don’t do this an Exception will be raised. Because of the way that Binding.of_caller is implemented it has to be done this way.
Full article: http://apidock.com/rails/v1.1.6/Binding/of_caller/class