Hi, On Mar 19, 11:27 am, alux <alu...@googlemail.com> wrote:
> user=> (time (fib0 35)) > "Elapsed time: 20874.18345 msecs" > 24157817 > > user=> (time (map fib0 (iterate inc 1))) > "Elapsed time: 0.913524 msecs" > (2 3 5 8 13 21 34 55 89 144 ...) > > Everything fine. > Now what puzzles me: > > user=> (time (map fib0 (range 100))) > "Elapsed time: 1.248203 msecs" As you write in your subject. You are caught by laziness. Wrap the map in a doall. (time (doall (map fib0 (iterate inc 1))) (time (doall (map fib0 (range 100))) (Don't forget to set print-length!) What happens? The map returns not a list of sorts but an object, which computes the result when it is requested. So it completes very fast, hence the short time reported by the time call. Now outside the time call the object is received by the Repl which triggers the suspended computation and prints the result. So the actual work happens outside the time call. On the other hand, wrapping the map into a doall will realise the computation immediately (that is inside the time call) and work will actually show up in form of a longer time reported by time. Sincerely Meikel -- 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 To unsubscribe from this group, send email to clojure+unsubscribegooglegroups.com or reply to this email with the words "REMOVE ME" as the subject.
