On 1 May 2010 03:19, Mark J. Reed <markjr...@gmail.com> wrote: >> Another version: >> >> (defn pairup [& args] >> (map vector args (rest args))) > > Nope, that doubles the middle elements: > user=> (pairup 1 2 3 4) > ([1 2] [2 3] [3 4])
Ouch, right, forgot to include take-nth: (defn pairup [& args] (take-nth 2 (map vector args (rest args)))) I was curious to see how much of a problem the building of vectors would be for the simple case of (apply pairup (range 20000)). Preliminary timing data indicates that this version has slightly longer running times with a larger variance; fastest runs for this pairup and the explicit cons pairup are about the same, but this pairup slows down to up to 2x that time per run much more often than the explicit cons pairup does (plus there are more super-long runs). Both go through (range 20000) in somewhere between 7 and 62 ms, so it might be pointless to even go on measuring this with more precision. But I'll still post this in case somebody else would enjoy a silly microbenchmarks at this time too. :-) Sincerely, Michał -- 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
