So, if a list whose first element is a vector is provided after a get or a put in alt!, then that's treated as the binding form/code to be executed if that succeeds, but if a non-list is provided, then that is treated as a value to return if that action was taken (and that value is evaluated before any operation happens)?
On Friday, August 15, 2014 8:35:05 AM UTC-4, Daniel Solano Gómez wrote: > > On Thu Aug 14 19:04 2014, dgrnbrg wrote: > > You're all right--that was a cut & paste error. I meant that I see this > > behavior with alt!!, not alts! > > With alt!!, it should probably be something like: > > (let [result (alt!! [[inner-chan e]] ([v] (if v > :put-a-value > :channel-closed)) > :default :failed-to-put > :priority true)] > (println result)) > > I hope this helps. > > Sincerely, > > Daniel > > > > > On Thursday, August 14, 2014 3:31:45 PM UTC-4, Ghadi Shayban wrote: > > > > > > What Daniel said. The call is incorrect, its args are alt-shaped, but > it > > > calls alt*s*. > > > > > > alt is the macro that is shaped like cond. > > > alts is the function that takes a vector > > > > > > Both take splatted options at the end. > > > > > > Can never use single bang* except within go.* > > > > > > go => ! > > > thread => !! > > > > > > Unfortunately if the two are confused, the exception will happen... > > > probably elsewhere. > > > > > > On Thursday, August 14, 2014 2:46:22 PM UTC-4, Eric Normand wrote: > > >> > > >> Hi there, > > >> > > >> The :default option is for a *value* that should be returned if none > of > > >> the channels are available. The expression is evaluated *before* the > > >> async/alts! call happens (just like normal parameters). > > >> > > >> I think you are misunderstanding alts!. It should be used like this > > >> > > >> (let [[val ch] (async/alts! [[inner-chan e]] :default :default)] > > >> (if (= :default val) > > >> (println "inner-chan was not ready") > > >> (if val > > >> (println "did the put to inner-chan") > > >> (println "inner-chan is closed")))) > > >> > > >> I hope that helps. Let me know if you have any more questions. > > >> > > >> Eric > > >> > > >> On Thursday, August 14, 2014 11:03:01 AM UTC-5, dgrnbrg wrote: > > >>> > > >>> When I use alts!, it seems that both the put and :default action run > > >>> every time. I've included the code sample below: > > >>> > > >>> (let [inner-chan (async/chan (async/buffer 1000)) > > >>> mult (async/mult inner-chan) > > >>> (async/thread > > >>> (while true > > >>> (let [e (.take linked-blocking-queue)] > > >>> (async/alts! > > >>> [[inner-chan e]] (println "did the put") > > >>> :default (println "failed to put") > > >>> :priority true))))) > > >>> > > >>> > > >>> Elsewhere in the code, I tap the mult before I start putting > elements > > >>> onto the linked-blocking-queue. For every element I put onto the > LBQ, I see > > >>> both messages: "did the put" and "failed to put". What is going on > here? > > >>> > > >> > > > > -- > > You received this message because you are subscribed to the Google > > Groups "Clojure" group. > > To post to this group, send email to clo...@googlegroups.com > <javascript:> > > Note that posts from new members are moderated - please be patient with > your first post. > > To unsubscribe from this group, send email to > > clojure+u...@googlegroups.com <javascript:> > > 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+u...@googlegroups.com <javascript:>. > > For more options, visit https://groups.google.com/d/optout. > -- 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.
