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@yayitswei
Last active August 29, 2015 14:08
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Unexpected behavior using try/catch in a go block
(ns queue-test
(:require [clojure.core.async :as async :refer [>! <! chan go go-loop put!]]))
(defn process! [item]
{:pre [item]}
(println "processing:" item))
(defn init! []
(let [q (chan)]
(go-loop []
(try (process! (<! q))
(catch Exception e
(.printStackTrace e)))
(recur))
q))
(defn test! []
(let [q (init!)]
;; the first queue fails the preconditions for process!
(put! q false)
;; I expect this one to work, but it doesn't in practice
(put! q true)))
(defn test2! []
(let [q (init!)]
;; without the first failing put!, this works as expected
(put! q true)))
@brandonbloom
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@halgari bug?

@brandonbloom
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Hm, Gist changed. Was a simpler repo a bit ago.

@yayitswei
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Author

I've just added two tests and a bit more explanation. test! fails and test2! works as expected.

Also swapped out (go (<! ..)) for put!, per your suggestion.

@laczoka
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laczoka commented Oct 28, 2014

should catch Throwable instead of Exception

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