I'm not completely sure what you're trying to do, but I think reduce can help you here. For example:
(reduce (fn [acc x] (if (odd? x) (conj acc x) acc)) [] [1 2 3 4 5 6]) returns: [1 3 5] Reduce is good for when you want iterate over one data structure and optionally update another data structure. Timothy On Mon, Sep 22, 2014 at 12:45 PM, J David Eisenberg < jdavid.eisenb...@gmail.com> wrote: > As part of a larger program, I'm testing a function that will turn a > string of days on which a class occurs (such as "MWF") into a list of seven > numbers: (1 0 1 0 1 0 0). > I first translate"TH" (Thursday) to "R" and "SU" (Sunday) to "N" to make > things a bit easier. > > I came up with the following code: > > (defn days-number-maker > "Recursively compare first item in days of week with > first item in string of days. If matching, add a 1, > else add a zero to the result" > [all-days day-string result] > (if (empty? all-days) (reverse result) > (if (= (first all-days) (first day-string)) > (recur (rest all-days)(rest day-string) (conj result 1)) > (recur (rest all-days) day-string (conj result 0))))) > > (defn days-to-numbers > "Change string like MTTH to (1 1 0 1 0 0 0)" > [day-string] > (let [days (clojure.string/replace > (clojure.string/replace day-string #"TH" "R") #"SU" "N")] > (days-number-maker "MTWRFSN" days (list)))) > > The good news: the code works. The bad news: I'm convinced I'm doing it > wrong, in the moral purity sense of the word. Something inside of me says, > "You could have just used (map...) to do this the *right* way," but I can't > see how to do it with (map). So, my two questions are: > > 1) Is there such a thing as "the Clojure way," and if so, > 2) How can I rewrite the code to be more Clojure-ish? > > -- > 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 unsubscribe from this group and stop receiving emails from it, send an > email to clojure+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/d/optout. > -- “One of the main causes of the fall of the Roman Empire was that–lacking zero–they had no way to indicate successful termination of their C programs.” (Robert Firth) -- 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 unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.