what's the difference between >! and put!? I thought they are identical before, but turned out put! is different

(defn afile?
  "Asynchronous file predicate.
   @param {!string} pathstr
   @return {!Channel} promise-chan receiving boolean"
  [pathstr]
  (assert (string? pathstr))
  (let [c (promise-chan)
        stat-ch (alstat pathstr)]
    (take! stat-ch
      (fn [[err stats]]
        (put! c (if-not err (.isFile stats) false))))
    c))

put! is used outside go block...

and this is in ClojureScript, calling Node.js APIs

not JVM Clojure

put! doesn’t block, and can be used outside go blocks AFAIK.