Not really. I find I very rarely write functions with explicit loops, because there is usually a higher-level function that encompasses what I want to do. For

Not really. I find I very rarely write functions with explicit loops, because there is usually a higher-level function that encompasses what I want to do. For example, in Clojure I'd write the flatten function as: (defn flatten [x] (remove sequential? (tree-seq sequential? seq x))) Other lisps probably have similar functions.