Anyone else runnig into with shadow-cljs 2.2.16:

Exception in thread "async-thread-macro-12" java.lang.NoClassDefFoundError: Could not initialize class shadow.cljs.devtools.server.reload_classpath$process_update$fn__59202
	at shadow.cljs.devtools.server.reload_classpath$process_update.invokeStatic(reload_classpath.clj:21)
	at shadow.cljs.devtools.server.reload_classpath$process_update.invoke(reload_classpath.clj:21)
	at clojure.lang.PersistentVector.reduce(PersistentVector.java:341)
	at clojure.core$reduce.invokeStatic(core.clj:6747)
	at clojure.core$reduce.invoke(core.clj:6730)
	at shadow.cljs.devtools.server.reload_classpath$process_updates.invokeStatic(reload_classpath.clj:45)
	at shadow.cljs.devtools.server.reload_classpath$process_updates.invoke(reload_classpath.clj:38)
	at shadow.cljs.devtools.server.reload_classpath$watch_loop.invokeStatic(reload_classpath.clj:75)
	at shadow.cljs.devtools.server.reload_classpath$watch_loop.invoke(reload_classpath.clj:63)
	at shadow.cljs.devtools.server.reload_classpath$start$fn__59234.invoke(reload_classpath.clj:92)
	at clojure.core.async$thread_call$fn__8239.invoke(async.clj:442)
	at clojure.lang.AFn.run(AFn.java:22)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	at java.lang.Thread.run(Thread.java:748)

hmm never seen that before

I think it's my fault

a wrong tools.reader version

it might be related to the new cljs version

which decided it was a good idea to ship the AOT bundle as the default

so you get their tools.reader version always

No I a old tools.reader in my project.clj

doesn't matter when the AOT version is on the classpath

Well now it works after removing tools.reader 1.1.2

I see cider support as been improved:

Very cool

Only thing that is not working anymore is file watching for some reason..

Hmm

yeah, fixed some piggieback things reported here https://github.com/clojure-emacs/cider/issues/2239

you need to tell me about these things. I wasn't even aware this was an issue 😛

what are those failed to parse warnings?

Oh sorry, I didn't dare you were so angry the last time you started cider 😛

11:38:40.868 [nREPL-worker-0] WARN  shadow.build.classpath - failed to parse javascript file: jar:file:/home/mitchel/.m2/repository/cljs-hash/cljs-hash/0.0.2/cljs-hash-0.0.2.jar!/js/sha256.js
[{:line 11, :column 9, :message "'identifier' expected"}] {  }
11:38:40.875 [nREPL-worker-0] WARN  shadow.build.classpath - failed to parse javascript file: jar:file:/home/mitchel/.m2/repository/cljs-hash/cljs-hash/0.0.2/cljs-hash-0.0.2.jar!/js/md5.js
[{:line 9, :column 9, :message "'identifier' expected"}] {  }
11:38:40.877 [nREPL-worker-0] WARN  shadow.build.classpath - failed to parse javascript file: jar:file:/home/mitchel/.m2/repository/cljs-hash/cljs-hash/0.0.2/cljs-hash-0.0.2.jar!/js/sha1.js
[{:line 9, :column 9, :message "'identifier' expected"}] {  }
11:38:41.633 [nREPL-worker-0] WARN  shadow.build.classpath - failed to parse javascript file: jar:file:/home/mitchel/.m2/repository/doo/doo/0.1.8/doo-0.1.8.jar!/runners/nashorn.js
[{:line 21, :column 39, :message "Semi-colon expected"}] {  }
11:38:42.192 [nREPL-worker-0] WARN  shadow.build.classpath - failed to parse javascript file: jar:file:/usr/lib/jvm/java-8-openjdk/lib/tools.jar!/com/sun/tools/hat/resources/hat.js

yeah I get frustrated easily by emacs .. doesn't mean I don't want it to work 😛

Ah ok

hmm I should turn off those warnings

Hmm I know why watching is not working:

(shadow-server/stop!)
shutting down ...
JS runtime disconnected.
Worker shutdown.
11:45:10.423 [nREPL-worker-2] WARN  shadow.cljs.devtools.server - shutdown failed ((rt/stop-all app)) {  }
java.lang.ThreadDeath: null
	at java.lang.Thread.stop(Thread.java:853)
	at clojure.tools.nrepl.middleware.interruptible_eval$interruptible_eval$fn__62024.invoke(interruptible_eval.clj:243)
	at clojure.tools.nrepl.middleware$wrap_conj_descriptor$fn__61733.invoke(middleware.clj:22)
	at user$eval74385$fn__74386$fn__74388.invoke(form-init5239952018706589785.clj:1)
	at shadow.cljs.devtools.server.nrepl$cljs_eval$fn__62323.invoke(nrepl.clj:171)
	at clojure.tools.nrepl.middleware$wrap_conj_descriptor$fn__61733.invoke(middleware.clj:22)
	at clojure.tools.nrepl.middleware.load_file$wrap_load_file$fn__62170.invoke(load_file.clj:79)
	at clojure.tools.nrepl.middleware$wrap_conj_descriptor$fn__61733.invoke(middleware.clj:22)
	at shadow.cljs.devtools.server.nrepl$cljs_load_file$fn__62334.invoke(nrepl.clj:192)
	at clojure.tools.nrepl.middleware$wrap_conj_descriptor$fn__61733.invoke(middleware.clj:22)
	at clojure.tools.nrepl.middleware.session$add_stdin$fn__62099.invoke(session.clj:238)
	at clojure.tools.nrepl.middleware$wrap_conj_descriptor$fn__61733.invoke(middleware.clj:22)
	at cider.nrepl$wrap_debug$fn__70069.invoke(nrepl.clj:161)
	at clojure.tools.nrepl.middleware$wrap_conj_descriptor$fn__61733.invoke(middleware.clj:22)
	at cider.nrepl$wrap_enlighten$fn__70077.invoke(nrepl.clj:187)
	at clojure.tools.nrepl.middleware$wrap_conj_descriptor$fn__61733.invoke(middleware.clj:22)
	at cider.nrepl$wrap_macroexpand$fn__70111.invoke(nrepl.clj:264)
	at clojure.tools.nrepl.middleware$wrap_conj_descriptor$fn__61733.invoke(middleware.clj:22)
	at cemerick.piggieback$wrap_cljs_repl$fn__62286.invoke(fake_piggieback.clj:31)
	at clojure.tools.nrepl.middleware$wrap_conj_descriptor$fn__61733.invoke(middleware.clj:22)
	at cider.nrepl$wrap_inspect$fn__70103.invoke(nrepl.clj:224)
	at clojure.tools.nrepl.middleware$wrap_conj_descriptor$fn__61733.invoke(middleware.clj:22)
	at cider.nrepl$wrap_out$fn__70127.invoke(nrepl.clj:305)
	at clojure.tools.nrepl.middleware$wrap_conj_descriptor$fn__61733.invoke(middleware.clj:22)
	at cider.nrepl$wrap_pprint$fn__70035.invoke(nrepl.clj:107)
	at clojure.tools.nrepl.middleware$wrap_conj_descriptor$fn__61733.invoke(middleware.clj:22)
	at cider.nrepl$wrap_tracker$fn__70191.invoke(nrepl.clj:450)
	at clojure.tools.nrepl.middleware$wrap_conj_descriptor$fn__61733.invoke(middleware.clj:22)
	at shadow.cljs.devtools.server.nrepl$cljs_select$fn__62315.invoke(nrepl.clj:153)
	at clojure.tools.nrepl.middleware$wrap_conj_descriptor$fn__61733.invoke(middleware.clj:22)
	at clojure.tools.nrepl.middleware.pr_values$pr_values$fn__61940.invoke(pr_values.clj:22)
	at clojure.tools.nrepl.middleware$wrap_conj_descriptor$fn__61733.invoke(middleware.clj:22)
	at cider.nrepl$wrap_test$fn__70175.invoke(nrepl.clj:415)
	at clojure.tools.nrepl.middleware$wrap_conj_descriptor$fn__61733.invoke(middleware.clj:22)
	at cider.nrepl.middleware.pprint$handle_pprint_fn.invokeStatic(pprint.clj:49)
	at cider.nrepl.middleware.pprint$handle_pprint_fn.invoke(pprint.clj:44)
	at clojure.lang.Var.invoke(Var.java:385)
	at cider.nrepl$wrap_pprint_fn$fn__70025.invoke(nrepl.clj:88)
	at clojure.tools.nrepl.middleware$wrap_conj_descriptor$fn__61733.invoke(middleware.clj:22)
	at clojure.tools.nrepl.middleware.session$session$fn__62084.invoke(session.clj:192)
	at clojure.tools.nrepl.middleware$wrap_conj_descriptor$fn__61733.invoke(middleware.clj:22)
	at clojure.tools.nrepl.server$handle_STAR_.invokeStatic(server.clj:19)
	at clojure.tools.nrepl.server$handle_STAR_.invoke(server.clj:16)
	at clojure.tools.nrepl.server$handle$fn__62185.invoke(server.clj:28)
	at clojure.core$binding_conveyor_fn$fn__5476.invoke(core.clj:2022)
	at clojure.lang.AFn.call(AFn.java:18)
	at java.util.concurrent.FutureTask.run(FutureTask.java:266)

hmm what the heck?

are you connected to the shadow-cljs nrepl or still via lein?

Still via lein

why are you calling stop!?

Because I did (shadow/watch :app) but it wasn't recompiling

try reload! instead

Ah ok

it might still fail though

I will try hold on

no idea whats going on

Now i have this again:

Exception in thread "async-thread-macro-15" java.lang.NoClassDefFoundError: Could not initialize class shadow.cljs.devtools.server.reload_classpath$process_update$fn__59438
	at shadow.cljs.devtools.server.reload_classpath$process_update.invokeStatic(reload_classpath.clj:21)
	at shadow.cljs.devtools.server.reload_classpath$process_update.invoke(reload_classpath.clj:21)
	at clojure.lang.PersistentVector.reduce(PersistentVector.java:341)
	at clojure.core$reduce.invokeStatic(core.clj:6747)
	at clojure.core$reduce.invoke(core.clj:6730)
	at shadow.cljs.devtools.server.reload_classpath$process_updates.invokeStatic(reload_classpath.clj:45)
	at shadow.cljs.devtools.server.reload_classpath$process_updates.invoke(reload_classpath.clj:38)
	at shadow.cljs.devtools.server.reload_classpath$watch_loop.invokeStatic(reload_classpath.clj:75)
	at shadow.cljs.devtools.server.reload_classpath$watch_loop.invoke(reload_classpath.clj:63)
	at shadow.cljs.devtools.server.reload_classpath$start$fn__59470.invoke(reload_classpath.clj:92)
	at clojure.core.async$thread_call$fn__8239.invoke(async.clj:442)
	at clojure.lang.AFn.run(AFn.java:22)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	at java.lang.Thread.run(Thread.java:748)

which is probably the error that causes this

when doing (shadow/watch :app)

can you try adding a custom cljs version please?

[org.clojure/clojurescript "1.10.145" :classifier "slim"]

Sure

no AOT

wonder if that changes anything

restarting

don't forget lein clean as usual. doesn't affect shadow-cljs but I don't know what lein may have done

do you get the error immediately on startup or only after changing a file?

I get it after stopping and starting the server again and then running (shadow/watch :app)

I am running this to start it btw:

(do (shadow.cljs.devtools.server/start!) (shadow.cljs.devtools.api/watch :app) (shadow.cljs.devtools.api/nrepl-select :app))

that is fine

Could a circular dependency break shadow-cljs? Just thinking out loud here

circular how? cljs? no

so to break it you call (shadow.cljs.devtools.server/stop!) and then the start above again?

cljs.user> :cljs/quit
:cljs/quit
user> (shadow-server/reload!)
Worker shutdown.
shadow-cljs - HTTP server for :devcards available at 
:shadow.cljs.devtools.server/restarted
user> Exception in thread "async-thread-macro-4" java.lang.NoClassDefFoundError: Could not initialize class shadow.cljs.devtools.server.reload_classpath$process_update$fn__65735
	at shadow.cljs.devtools.server.reload_classpath$process_update.invokeStatic(reload_classpath.clj:21)
	at shadow.cljs.devtools.server.reload_classpath$process_update.invoke(reload_classpath.clj:21)
	at clojure.lang.PersistentVector.reduce(PersistentVector.java:341)
	at clojure.core$reduce.invokeStatic(core.clj:6747)
	at clojure.core$reduce.invoke(core.clj:6730)
	at shadow.cljs.devtools.server.reload_classpath$process_updates.invokeStatic(reload_classpath.clj:45)
	at shadow.cljs.devtools.server.reload_classpath$process_updates.invoke(reload_classpath.clj:38)
	at shadow.cljs.devtools.server.reload_classpath$watch_loop.invokeStatic(reload_classpath.clj:75)
	at shadow.cljs.devtools.server.reload_classpath$watch_loop.invoke(reload_classpath.clj:63)
	at shadow.cljs.devtools.server.reload_classpath$start$fn__65767.invoke(reload_classpath.clj:92)
	at clojure.core.async$thread_call$fn__9069.invoke(async.clj:442)
	at clojure.lang.AFn.run(AFn.java:22)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	at java.lang.Thread.run(Thread.java:748)

I do that several hundred times when working on shadow-cljs itself yet I have never seen that error

the error happens on the file change after reload!

hmm do you use tools.namespace?

Yes

but not during this process?

Hmm yes I have run go

That would make sense that it breaks it

I don't know why it would though. maybe its something related to the nrepl change I did

Maybe i should start running it externally

Let me try that out to see if that breaks

well I have shadow-cljs embedded in lein to develop it so it should work just fine

can you try just restarting it directly from the REPL without calling the tools.namespace stuff?

just trying to isolate if it might be trouble in your deps

Hold on wil restart it first

throw in a lein clean for safety

I'll also run a lein deps tree

hmm core async conflict might be related?

hmm shouldn't be no

didn't see anything from it on the stacktraces yet

I just restarted

en changed a file

and nothing happens

it does not reload

still the same error?

the core.async thread macro hasn't changed in forever so that shouldn't matter

I have no clue. it might be the piggieback change I did because that messes with the *ns* binding which is a bit scary

but piggieback does that so it should be fine

Very weird the only thing is broken is the watching and recompiling

the repl works like a charm

I don't get why that would be broken. I didn't touch that.

and why does it fail loading the class in the first place

such a weird error

wait does the reloading also not work if you just started it clean without stop! or reload! first?

Yes

which version were you on before upgrading?

2.1.21

I don't get why it fails on reload-classpath. I didn't touch that in forever

Only other conflicts with jars that I find is jackson-core but I cannot imagine that breaking anything

yeah doubtful

wait do you AOT compile maybe?

No

Would it help if I put shadow-cljs in verbose mode somehow?

probably not. there is not additional logging in that place.

I have never seen this error in several years of clojure. I don't understand why you'd get NoClassDefFoundError. clojure is supposed to create the class before loading it.

Hmm I do a set-refesh-dirs

And now it works

When I removed that call

I had this:

(set-refresh-dirs "dev/server" "src/main" "test" "src/cards")

[clojure.tools.namespace.repl :as tools-ns :refer [set-refresh-dirs]]

removal works.. I still had this from the fulcro template

I wonder why that would affect anything. will take a look at tools.namespace

I'll see if it stays fixed

Thank you for listening @thheller

It also keeps working after resets

good to know

@thheller Now I am running into: java.lang.NoClassDefFoundError: Could not initialize class shadow.build.warnings$get_source_excerpts$iter__60601__60605$fn__60606$fn__60607$fn__60609

Really weird that I am getting NoClassDefFoundError

@mitchelkuijpers so weird indeed

> val_waeselynck [17:28] @thheller I tend to have this sort of error after I uberjar my project while my code is running. I think this changes the class files in some way to messes up the REPL.

do you do anything like that?

but the shadow-cljs classes should never be written to disk anyways

I backed out of shipping AOT code because of errors like this

but I can't explain where this is coming from. which clojure version are you using?

1.9.0

I am now running it separately with the shadow-cljs command

did your clojure process use any classloader trickery?

immutant or some other container?

No nothing like that

Here I am @hlolli

cool, Im guessing you didn't set :devtools ?

:devtools {:http-root "public"
:http-port 8088
;; :http-handler dev.server/handler
:after-load visitor.main/init}

I just cloned and ran this: https://github.com/lauritzsh/reagent-shadow-cljs-starter

Maybe it’s too old.. I’ll update it

"devDependencies": {
    "shadow-cljs": "^2.0.115"
  }

I see that now lol

There it is!

Ohh, nice spinner

Wow, I might switch from lein/cljsbuild to boot/shadow in the same week, lol.

yup, I'm like a broken record repeating this tip, but you can basically start shadow-cljs watch and then start the backend to serve the output directory, you'll get the hot reload weather or not you're conencted to the localhost port given in the :devtools.

(and the hud)

ok

I assume it plays nicely with boot as well?

yes, if you keep the clojure seperated from the clojurescript, then it would also work well with python, node or any backend.

some folks are mixing lein and shadow in some fancy way, have no idea if that works with boot, and what the gain is from doing that.

@jmckitrick I know very little about boot and haven't done many tests. I know that it interferes a little with shadow-cljs related to caching and things. everything should work in theory but I really don't know.

happy to look at problems it you find any though

I greatly appreciate the offer! We’re doing the first official clojure products at work, and I’ll be on the hot seat for any issues we run into along the way 😧

the smoothest option is to just keep the CLJ and CLJS worlds separate. they don't benefit at all when you combine them and just cause headaches if your CLJS deps interfere with CLJ deps

Interesting. ok, duly noted.

Should I be surprised if the binary is much smaller than that produced by cljs-build?

not really. people frequently report this.

the config sets a couple of optmizations that you maybe didn't set when using cljsbuild

and cljsjs is pretty ineffecient as well

I might be sold, then. I’m going to spend the day tomorrow digging in deeper. So much for generative testing day, lol.

I’ve updated my guide on how to use javascript in cljs. My goal here is to have something to point people to when they ask about this on slack. I’d appreciate a read before I start sending it to folks just to make sure I’m not mischaracterizing something. https://gist.github.com/jmlsf/f41b46c43a31224f46a41b361356f04d

@thheller doesnt it incur extra overhead to separate front and back ends? In other words how do I serve up the front end page and assets separately from the backend? I assume I need to run Express?

@lee.justin.m you probably know the answer as well

during development you just serve the front end from the shadow-cljs development server

during production, you’ll compile the front end to a javascript bundle and then serve it as if it were a static resource from the backend

the only annoying thing is that you have a cors issue during development

So I can’t really keep the code entirely separate, then, right? The payload still needs to end up in the js directory of the server project

I was assuming you’ve got a SPA front end that connects via some kind of API that is running on clojure.

I wouldn't separate the code because you might want to share some code from the client and server

If you are running a templated backend then the “keep it separate” advice might be more complicated.

if you compile your code to say public/js and configure your server to serve static files from public you are all set

Or if you’re doing something like server side rendering, that might call for something different.

or the usual resources/public/js if you want to serve resources instead of files

@lee.justin.m reading over your gist

> The "double bundle" approach: same as (3)

shouldn't that be like (1)? you don't need to tell the compiler about the double bundle at all in theory

> "shoudl" typo

> I do not reccommend either of these approaches for now:

you do recommend #2 😉

I think it should say like (1) or (3) because you can do it either way (the two blog posts I link to do either either way)

wait nvm

one extra thing that shadow-cljs does that the default cljs externs inference doesn't do

since shadow-cljs fully processes all .js files it extracts some extra externs infos from them

might be worth mentioning

definitely

> Shadow-cljs's import syntax

that makes it sound like string requires are shadow-cljs only. they are not. if :npm-deps ever works out it should work identically in CLJS

Accurate? > Use shadow-cljs automated externs inference. Shadow-cljs will give you warnings when it can’t figure things out and you can just provide a type hint. Because shadow processes all of your JavaScript libraries, Shadow can infer externs from them, which is a real advantage over some other approaches relying on the built-in compiler’s extern inference.

damnit i edited this so much that some stuff is out of order now 🙂

in theory if externs inference for CLJS was perfect that would be enough. the extra JS processing just makes it a bit more reliable for now

is it true you can use figwheel with shadow if you want to?

no

okay fixing that

in your example config. remove clojure/clojurescript deps, they are provided. :http-handler push-state is the default now so you can remove that as well

>Note the :after-load entry point: this is what shadow-cljs will call when it hot reloads new code.

Note the :after-load symbol, this is what shadow-cljs will call after hot reloading code finishes.

or something like that

the "after" is key here, as before also exists

"when" is too ambiguous I think

you know i’m going to get rid of all that. it’s getting off topic

i just want to inform people about why shadow works better for imports

A quickstart guide should be separate.

I wouldn't bash cljsjs so heavily. It works pretty darn well IFF you are only using a very small amount of it. say if you are only using React it is pretty darn good for that.

problem is that it really doesn't scale well past say 3 packages

It was a freaking nightmare for me 🙂

yeah probably starts breaking at 2 already

It’s so complicated! Here, learn this barely documented externs syntax! Here, learn boot!

but I used it for a very long time when I just wanted react is it worked well for that

Well the real point of this document is for people who use lots of react libraries

yeah making custom cljsjs packages is horrible. I wouldn't want to do that either

And it doesn’t work for that at all

true

I’ll look for places to tone it down. I don’t want to be mean to people who spent their free time on something.

> Can use standard CDN distros?

shadow-cljs: yes

really?

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

oh shit that’s pretty cool!

pretty good overview of the current options overall

you could also mention that shadow-cljs actually allows full 100% interop (ns demo.bar (:require ["./foo" :as foo])) would load demo/foo.js from the classpath

and that JS can actually require CLJS via import cljs from "goog:cljs.core"; cljs.assoc(nil, "foo", 1)

this is not 100% perfect yet but it is a goal of mine to support compilation of JS projects that just want to start using CLJS without having to rewrite everything

so just start by introducing things gradually one file at a time or so 😉

thats definitely something CLJS can't do 😉

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

in theory I could add support for https://www.webjars.org/ which also mirrors npm

Okay I added these two points. It’s a little OT but I agree it’s worth mentioning. * Shadow-cljs actually lets you load any JavaScript file on the classpath. So, (ns demo.bar (:require ["./foo" :as foo])) would load demo/foo.js from the classpath. [This is experimental.](https://shadow-cljs.github.io/docs/UsersGuide.html#_requiring_js) * It also allows interop in the other direction, [by embedding cljs in an existing JavaScript app](https://shadow-cljs.github.io/docs/UsersGuide.html#target-npm-module).

npm-module isn't related to that

oh oops

well it kind of is but its a different thing altogether

since webpack or whatever is doing the packaging then

shadow-cljs just spits out webpack compatible code basically

its complicated 😛

what’s the relevant section of the manual?

dealing with js files I linked above

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

hmm thats still missing an example for how the JS could talk to CLJS

this part? https://shadow-cljs.github.io/docs/UsersGuide.html#_access_cljs_from_js

oh hehe yes. guess I did mention it.

oh doh , { keyword } this doesn't work anymore with the latest closure compiler

only cljs.keyword but the direct refer was broken by them 😞

or does it? I'm confused

too tired. I need sleep.

go to sleep. 🙂 thanks so much for your help. i feel better about this document now.

thanks for writing it. sounds a bit like one giant ad for shadow-cljs. I like it 😉

i view it as essential guidance for any js->cljs transition 🙂

alright I'm off to bed. gn8