I'm sorry, but won't these two examples add the method just to arrays? The author is intentionally trying to add a single method that will work for all collecti

I'm sorry, but won't these two examples add the method just to arrays? The author is intentionally trying to add a single method that will work for all collections, both scala's and non-scala's, and will always return a collection of the same type as the one the method was called on. Can you show how to easily do that in a dynamic language?