[smenko]

Yes, isUpper is a method on Char, _.isUpper is a lambda that is given to exists, which is a method on the trait TraversableOnce, which String happens to implement, along with many other things, such as Option and Future. Where's the OO and where's the functional? In the Clojure example in the OP does the author realise that all of those things are in effect Java objects? Does any of this make the code better or worse?

But that's not the point, the Scala code provided there is beyond ignorant, whoever wrote that has no right to be judgemental of the language or its founding paradigms.