I was able to get yarn shadow-cljs cljs-repl :main to evaluate code once I had yarn shadow-cljs watch :main running somewhere else and my browser loaded. That sounds to me like the problem is firmly on the #cider side of things. Thanks for the thoughts here and for the excellent REPL troubleshooting documentation--that cleared some stuff up for me.

Not sure if this is the best solution, but we’re now using this in release mode:

:release {:compiler-options {:output-feature-set :es5}}

this should absolutely not be required. can you try if this is maybe related to incremental compiles?

if you get the error on shadow-cljs release just wipe the .shadow-cljs/builds/<your-build-id>/release dir and try again

if that works it appears to be related to incremental compiles

I just fixed the other issue but your problem description seems different so I'm not sure they are actually related

especially since switching the :output-feature-set will cause a cache wipe anyways

Thanks for your feedback @U05224H0W. Wiping out the .shadow-cljs folder unfortunately doesn’t fix it. And I do think it’s the same issue, because it’s also for me the Col element in react-bootstrap (now version 2.0.0, no longer rc). I just now updated shadow-cljs to 1.16.2. The steps that I’m doing: • rm -rf .shadow-cljs node_modules • npm i • npx shadow-cljs -A:my-client server • npx shadow-cljs -A:my-client release :my-client I then request my HTML page through the dev server and I get TypeError: $jscomp.makeIterator is not a function in the JS console. Leaving out the Col element makes the error disappear. I can try to make a small reproduction project if that helps.

so as far as I can tell the problem seems to be that the closure compiler rewrites some code expecting some polyfills (eg. $jscomp.makeIterator) to be available. normally when it does such replacements it also ensures that the polyfills will be injected itself. somehow something in the Col file however only causes the rewrite without ensuring its actually present

the fix I made seemed to work around the problem somewhat reliably but I guess not for your case

so a repro might help track it down further although I made a minimal case that ONLY included Col and that worked just fine

so dunno how to make it more minimal 😛

but I have to ask since it is such a common mistake: when you updated shadow-cljs did you actually update it in deps.edn or only package.json?

I updated both 🙂

Maybe your reproduction scenario was too minimal then? 😛 I’ll try to setup something up later this morning!

@U05224H0W I have created a small repo that reproduces the issue for me. I think for the error to occur, the Col must be inside a Row and/or Container; just the Col may not trigger that code path. https://github.com/svdo/shadow-cljs-948

this works fine for me?

Really? 🤯 I’ll have a coworker try as well and get back. Very strange. You did the steps exactly like I described in the README right?

nah nevermind got it reproduced

https://github.com/google/closure-compiler/issues/3890

I'll see about adding a workaround

it should work in 2.16.4 if you add :js-options {:force-library-injection #{"es6/util/makeiterator"}} to your build config

@U05224H0W Your skills never cease to amaze me, this is great Thomas!!!