Although now I see that this usage is breaking the "side-effect free" rule. So actually this is probably not what you want to do. :)
Now I'm with you and thinking that atoms are not a proper fit for PersistentQueue. Maybe someone from the conj can shed some light on this. Allen On Wed, Nov 9, 2011 at 8:56 PM, Allen Johnson <akjohnso...@gmail.com> wrote: > In your example yes, but you could make it atomic by placing the > functionality in a function of it's own: > > ;; queue processing actions > (defn process-item [queue] > (println "Processed item:" (peek queue)) > (pop queue)) > > ;; usage > (let [queue (atom (into PersistentQueue/EMPTY [1 2 3]))] > (swap! queue process-item) ; prints 1 > (swap! queue process-item) ; prints 2 > (swap! queue process-item)) ; prints 3 > > Probably better examples but that's the basic idea. > > Allen > > On Wed, Nov 9, 2011 at 8:46 PM, Takahiro Hozumi <fat...@googlemail.com> wrote: >> Hi, >> >> To avoid peeking same element of a queue, I think PersistentQueue must >> be stored in ref not atom. >> Is this correct? >> >> ;;Ref: safe >> (dosync >> (let [item (peek @r)] >> (alter r pop) >> item)) >> >> ;Atom: unsafe >> (let [item (peek @a)] >> (swap! a pop) >> item)) >> >> Thanks. >> >> -- >> 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
