Clojurians Log v2
clojurescript 2024-12-25
How do you deal with AsyncIterable? Three years ago, the https://ask.clojure.org/index.php/10896/how-to-work-with-asynciterable-interface-in-cljs came up, resulting in a https://clojure.atlassian.net/browse/ASYNC-239 which doesn't seem to have moved since then. Any new insights, maybe?
For context: The values() method of the FileSystemDirectoryHandle interface returns a new asynchronous iterator for the iteration of the value of the entries within the FileSystemDirectoryHandle on which this method is called.
Problematic?
As I mentioned - it loses ^js and any other type hints. Not sure about other metadata.
IIRC, depending on how you use it, it might also end up generating a lot of code that, if rewritten with plain promises, could be a fraction of that.
Fair enough.
Oh, more likely - I'd write that bit in JS and use it from CLJS. Similar to how you might do some things in Java and then use them in CLJ.
Just curious: you avoid core.async at all cost?
In CLJS - yes. Well, "at all costs" sounds rough but it actually isn't a big deal because there's not that much incentive in the first place.
the incentive is elegant code, which is subjective, granted.
(defn iter->seq [iter]
(go-loop [acc []]
(let [el ((if (.-done el)
acc
(recur (conj acc (.-value el)))))))
(defn list-opfs [dir]
(go (let [root-storage (sub-dir (values (.values sub-dir)]
(async/take! (iter->seq values) #(doseq [v %] (.dir js/console v))))))
Indeed. For me, "elegance" and "adding a problematic impossible-to-debug dependency" are at odds with each other.
Certainly.
How do I create custom js/Error class in clojurescript?
class MyError extends Error {
constructor(message, options) {
// Need to pass `options` as the second parameter to install the "cause" property.
super(message, options);
}
}If you use shadow-cljs, there's [shadow.cljs.modern :refer [defclass]].
If not, then you can create classes in JS without using class or extends: https://playfulprogramming.com/posts/js-classes-without-keyword#Extend-a-functional-class-using-Objectcreate