asynchronous - Clojure RethinkDB subscribe to a changefeed -


i using clojure driver rethinkdb. want change feeds query. here have far :

(defn change-feed [conn]   (loop [changes (future                    (-> (r/db "mydb")                        (r/table "mytable")                        r/changes                        (r/run conn)))]     (println "date : " ((comp :name :newval) first @changes)) ;;prints nil     (recur (rest changes))))

it blocks in repl when called (which normal). add data using rethinkdb interface. prints nil , following error :

illegalargumentexception don't know how create iseq from: clojure.core$future_call$reify__6736  clojure.lang.rt.seqfrom (rt.java:528)

what doing wrong ? able :

  • take items future
  • know how many items can take @ once (if several waiting)

note : plan use manifold manipulate result in end, solution using fine.

i don't think need future block there, cursor returned clj-rethinkdb library block until it's ready.

you use doseq instead of loop might more natural.

i'm maintainer of clj-rethinkdb, , we've got changes coming down pipe present core.async interface , new cursor abstraction. if want use early, checkout https://github.com/apa512/clj-rethinkdb/pull/55


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