Clojure - Why does execution hang when doing blocking insert into channel? (core.async)

Question

Consider the following snippet:

(let [chs (repeatedly 10 chan)]
  (doseq [c chs]
    (>!! c \"hello\"))
  (doseq [c chs]
    (println (

        

Answer 1

That channel has no buffer, and >!! is blocking. Refer to the examples for this exact case. They spawn a second thread for this reason - to prevent blocking the main thread. Using a goroutine, as in your question, operates on a similar principle.

You can also create the channel with some buffer space - (chan 1)