Essentially, you are using two accumulators: acc and (first coll). You can probably use reduce for this purpose by (reduce f [acc (first coll)] (rest coll)) adjusting the starting accumulator accordingly and altering f to be (fn [[acc coll-acc] item] ...)
Frankly, it would probably be more readable to just use loop. That's what I do if I have more than one accumulator. On Sun, Dec 9, 2012 at 7:39 AM, Alexander Semenov <bohtva...@gmail.com>wrote: > Hi, folks. > > I'm wondering if Clojure library has 'reduce' function version which is > like (reduce f coll) - i.e. it applies function to coll elements without > the initial value but at the same time allows to use external accumulator > which is passed to f as well. Better look at the code: > > (defn reduce-with-acc > "Applies f to first two coll elements and acc producing new acc value for > subsequent f calls. Returns acc. On singleton or empty collection returns > acc immediately." > [f acc coll] > (loop [a (first coll) acc acc s (next coll)] > (if (seq s) > (let [b (first s)] > (recur b (f a b acc) (next s))) > acc))) > > Regards, > Alexander. > > -- > 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 -- 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
