On Sat, Aug 7, 2010 at 8:27 PM, David Cabana <drcab...@gmail.com> wrote: > Using a vector instead of a list as the accumulator makes it possible > to skip the mapping of reverse used in the earlier version of pw: > > (defn pw [f? x] > (let [phi (fn [a e] > (if (f? e) > (cons [e] a ) > (cons (conj (first a) e) > (rest a))))] > (reverse > (reduce phi [] x)))) >
conj sounds like 'append' to me which I have no idea about the performance characteristics in clojure(it is a no-no in F#, Haskell ++ is better but would grow the stack). list cons then reverse would give me predictable O(2n). That is why I usually rather go for the cons then reverse route. thanks for the example BTW, as I am learning my clojure basics via these excercises. -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
