@dnolen I created a minimal example with the bug here: https://github.com/talgiat/cljs-spec-bug. Can’t open a bug in cljs jira (don’t have permission to do so).

you can file bugs without an account here: https://clojure.atlassian.net/servicedesk/customer/portal/1

they'll go into the triage queue and we'll turn them into a ticket

Is there a good way to turn a DOMRect object into map, without having to list all the attributes?

thanks @alexmiller reference is SUPPORT-25 (https://clojure.atlassian.net/servicedesk/customer/portal/1/SUPPORT-25)

I'm trying to use the :global-exports feature of foreign-libs and having trouble in this case:

:provides ["@foo/bar"]
      :global-exports '{@foo/bar Bar}

So I think I found a bug in the compiler, and made a fix that works for me - but unsure it is the right way to fix:

https://github.com/jamesmintram/clojurescript/commit/e70e5159d2c58e53d0dfdf89f386722ed110c586

My app.js had the following in it:

document.write('<script src="target\public\cljs-out\common/goog/deps.js"></script>');
document.write('<script src="target\public\cljs-out\common/cljs_deps.js"></script>');
document.write('<script>if (typeof goog == "undefined") console.warn("ClojureScript could not load :main, did you forget to specify :asset-path?");</script>');
document.write('<script>goog.require("figwheel.core");</script>');
document.write('<script>goog.require("figwheel.main");</script>');
document.write('<script>goog.require("figwheel.repl.preload");</script>');
document.write('<script>goog.require("devtools.preload");</script>');
document.write('<script>goog.require("figwheel.main.css_reload");</script>');

the .cljs.edn file had the following setting: :output-dir "target\\public\\cljs-out\\common" (this is on Windows) I'll add that deps.edn made it super easy to download local copies of figwheel and clojurescript + tweak/add debug statements as required.

I’m looking for help on JS interop, specifically making sure that things also work under advanced compilation. I have found several things at play here, but I don’t understand what each of them do and when/which to use: - ^js type hints - goog.object - cljs.oops - mfikes new bean library

Is there any documentation that ties this all together? Also, when I find certain things not working, how do I approach debugging this? I’m sprinkling ^js throughout my code atm, and that seems to improve things, but I don’t know if that’s the right way to go.

(I don’t think it really matters, but this is a shadow-cljs based react-native clojurescript project)

usually the first question asked when this stuff happens is for you to give an actual problem statement. are things currently not working under advanced compilation?

https://clojurescript.org/reference/compiler-options#pseudo-names and this can help with reading the advanced output

Sure, I’ll give a concrete example, but I’m really looking for general principles more than solutions to specific problems. Like: can I use normal JS interop at all safely? E.g. some react native component calls my callback with a JS object as a parameter and I use normal JS interop notation to access it. Is that OK? Must I include ^js? Is that sufficient? Specifically as an example:

(defn cell [^js details]
  (let [item (.-item details)
  ...))

(defn Staff [styles]
  [:> rn/View styles
   [:> rn/FlatList
    {:data ^js @view-model
     :extra-data ^js @cursor-info
     :key-extractor (fn [item _] (str (.-measureNumber item)))
     :horizontal true
     :Cell-renderer-component ViewOverflow
     :List-header-component #(r/as-element [header])
     :List-footer-component #(r/as-element [footer])
     :Item-separator-component #(r/as-element [separator %])
     :render-item #(r/as-element [cell %])}]])

:data ^js @view-model those don't matter

in this case (.-item details) that will result in details.item in the code. the closure compiler may decide to rename this to something shorter. the ^js hint will cause externs to be added that will prevent the renaming of the .item property (which you need for JS interop)

Right, and is that a shadow-cljs feature or is that standard CLJS?

standard CLJS (commonly named "externs inference")

Can I infer from that that normally I don’t need to use something like bean or cljs.oops or goog.object directly?

well bean is for different stuff

cljs-oops you don't need yes

Is there tooling that can warn me about missing ^js type hints? I have run shadow-cljs check but that doesn’t catch everything.

https://shadow-cljs.github.io/docs/UsersGuide.html#infer-externs

Ahh now I read that again it starts to make sense, last time I read it, it didn’t yet 🙂

So as an example, it says:

153 |      :key-extractor (fn [item _] (str (.-measureNumber item)))
---------------------------------------------^----------------------------------
 Cannot infer target type in expression (. item -measureNumber)
-

:key-extractor (fn [^js item _] (str (.-measureNumber item)))

yep thats correct

Is there a reason to ever not use :infer-externs :auto?

well the warnings aren't 100% accurate so you may get warnings and add typehints when they aren't actually needed

At the cost of some performance loss? I can live with that for now 🙂

And cljs-bean is then probably more like a convenience thing to simplify destructuring JS objects and things like that?

yes

(sorry to have mislead earlier. I'm learning new stuff. thanks @stefan.van.den.oord)

Thanks @thheller, extremely insightful and helpful as always. I’ll keep the donation on Patreon active for a while longer 😛

Release build works now 🎉

Hello! Trying to run cljs tests either directly with phantom ....js either thru lein doo there is same error ReferenceError: Can't find variable: Map I find out many things about it in internet, but all of them are not with clojure. What shoud I do?

phantomjs might not support Map which is a new-ish JS hashmap implementation

might need to find out what is using Map or add proper polyfills

I find a lot of examples how to add polyfils , but all of them are in js/ts/etc. How and where I can do it in cljs project?

I think there should be a phantomjs config you can add it too?

not sure in the case of doo

but maybe there is another way for headlesstesting cljs from command line for CI? not unworked phantom, but maybe another V8 source? And not node either

dunno about all the testing options. shadow-cljs has something built-in for karma that some people use

thats all I used in the past

thanks, I'l try to play with phantom config a little and then will look for another way