Hey everyone, I've developed a predicate library to handle stuff like this.
http://github.com/francoisdevlin/devlinsf-clojure-utils/ Check out lib.devlinsf.pred-utils There are two methods, ever-pred? and any-pred? designed to handle this. Here's an example ;;mimics OR user=> (filter (any-pred? odd? zero?) (range 0 10)) (0 1 3 5 7 9) ;;mimics AND user=> (filter (every-pred #(zero? (mod % 5)) #(zero? (mod % 3))) (range 1 61)) (15 30 45 60) They are based on every? & some, so they are appropriately lazy. You can check my docs for more information. Hope this helps. On Oct 20, 8:52 am, Meikel Brandmeyer <m...@kotka.de> wrote: > Hi, > > On Oct 20, 3:08 am, Dmitry Kakurin <dmitry.kaku...@gmail.com> wrote: > > > (defn multi-filter [filters coll] > > (reduce > > (fn [res e] > > (map (fn [f r] (if (f e) (conj r e) r)) > > filters > > res)) > > (repeat (count filters) []) > > coll > > ) > > ) > > I think this basically equivalent to the juxt solution. Besides your > are using sequence, where juxt uses vectors directly. Maybe that is a > bit faster? Dunno. > > Stylistic: you should not put the closing parens on dedicated lines. > They are normally collected on the last line. While this is only a > style issue, you should get used to it, since 99.9% of all code at in > the wild will use that style... > > > Interestingly enough replacing map with eager-map in multi-filter > > definition gives very insignificant boost in perf (less than 10%), so > > I've decided to leave it as is. > > May be there are improvements possible to my emap definition? > > > (defn emap [f c1 c2] > > (loop [s1 (seq c1) s2 (seq c2) res [] ] > > (if (and s1 s2) > > (recur (seq (rest s1)) (seq (rest s2)) (conj res (f (first s1) > > (first s2)))) > > res))) > > Use next instead of the seq-rest combination. > > 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 -~----------~----~----~----~------~----~------~--~---
