no

the Closure compiler is not really a compiler, it’s an optimizer. with optimizations :none, it is not called. otoh, Clojurescript is a compiler, it translates cljs to js. so with no optimizations you get the latter but not the former.

at least that’s my understanding.

that's kind of crazy then; I would expect a clojure "cljs -> js" translator to be slightly faster

Faster than what? The clojurescript compiler is cljs->js.

what’s crazy about it? makes perfect sense to me.

I have a hard time seeing how translating 3000 lines of cljs into js should take 40 seconds

shrug. i guess it depends on which 3000 lines.

e.g. does your 3K loc contain 5K namespaces?

Is this not correct?

(ns foo
  (:refer-clojure :rename {map clj-map
                           filter clj-filter
                           or clj-or
                           if clj-if
                           reductions clj-reductions}))

Also: Is there a way to prevent all builtins from being included in an ns? The "differences from clojure" page says only :rename and :exclude are supported...

@mrchance I wonder if you can actually rename if, given that it is not a Var

@mfikes Good point, that might be the case. I think it still goes wrong for the other vars too though, will check

The funny thing is that it initially compiles without problems, but complains whenever I change something there

What complaints do you see?

map already refers to: cljs.core/map being replaced by: foo/map
filter already refers to: cljs.core/filter being replaced by: foo/filter at line 17, column 1 in file foo/core.cljs
reductions already refers to: cljs.core/reductions being replaced by: foo/reductions at line 20, column 1 in file foo/core.cljs

After removing the or and if

@mrchance That appears to be a bug in the ClojureScript compiler, surrounding the :rename feature

Specifically, map still resolves

Looks that way 😞

The :refer-clojure is recognized and parsed correctly at least, when I put a typo in there it doesn't compile anymore...

Maybe code using :refer-clojure isn't reloadable for some reason?

@mrchance https://dev.clojure.org/jira/browse/CLJS-2292

@mfikes Awesome, thanks! Gonna watch that bug now 🙂

Cool. :rename support is relatively new—still less than 1 year old at this point.

@mfikes hrm, I’m not sure if your assessment is correct

I think :exclude is needed, even in Clojure

2 different REPL sessions:

boot.user=> (refer-clojure :exclude [map] :rename '{map lol})
nil
boot.user=> map
#object[clojure.core$map 0x5e5b5265 "clojure.core$map@5e5b5265"]
boot.user=> lol
#object[clojure.core$map 0x5e5b5265 "clojure.core$map@5e5b5265"]
boot.user=> (defn map [])
WARNING: map already refers to: #'clojure.core/map in namespace: boot.user, being replaced by: #'boot.user/map
#'boot.user/map

boot.user=> (refer-clojure :rename '{map lol})
nil
boot.user=> map
#object[clojure.core$map 0x79ac87f2 "clojure.core$map@79ac87f2"]
boot.user=> lol
#object[clojure.core$map 0x79ac87f2 "clojure.core$map@79ac87f2"]
boot.user=> (defn map [])
WARNING: map already refers to: #'clojure.core/map in namespace: boot.user, being replaced by: #'boot.user/map
#'boot.user/map

@anmonteiro That's interesting. refer-clojure and (ns ... (:refer-clojure ...) have different behaviors in Clojure with respect to whether renamed symbols are still visible

@anmonteiro My guess in the above is that boot.user is already "tainted" with core symbols, and that's why (refer-clojure :exclude [map]) doesn't really do anything about the map that has already been referred. You can see the same in a fresh namespace.

(ns foo.bar (:refer-clojure :rename {map lol}))

(ns foo.bar)

I see

makes sense

Yes, as Eric Norman aptly puts it, at it's core Clojure is a very mutative language 🙂

^ http://www.lispcast.com/clojure-is-imperative

anyone know how to interop cljs funtions as javascript functions?

I know you can do (ClassName.) which is equivalent to new ClassName(), but I want to be able to get the actual value of ClassName (for prototype stuff)

it looks like ClassName. is the same as ClassName

the . indicates execution - just use ClassName without it

thanks!

i'm seeing an exception trying to start an isomorphic ClojureScript app (the Node server) with cljsjs/react-dom in 1.9.845. It breaks trying to require React as a Node module (e.g., require('react')). I've done some debugging, and in previous versions of ClojureScript, specifically 1.9.671, exports and module do not exist which triggers a different, successful code path at the start of react-dom.inc.js. Looking further it appears a change to CLOSURE_IMPORT_SCRIPT in goog/bootstrap/node.js to how files are required is the culprit (specifically the change to use require over nodeGlobalRequire, which happened in https://github.com/clojure/clojurescript/commit/fc0989f1b44b97547410a2d2c807f16430b47486). Does this sound familiar, has anybody else seen this behavior, is this a legitimate issue, or am I doing something I shouldn't be doing? Thanks for the help!

@crteal I don’t quite understand your problem, but is requiring react from node_modules not an option?

we did some changes around Node.js bootstrapping but all it should do is not allow you to require JS modules processed by Closure

i was previously using cljsjs/react and cljsjs/react-dom in tandem with om-next

makes sense

i could probably use node_modules now, but i thought everything would "just work"

from what i read about the release, and lurking a bit here (and elsewhere)

so if you’re using CLJSJS/React, where are you doing require('react')?

i'm not, the unminified source from Facebook of react-dom.js is

oh

I’ve ran into this before

just install react from NPM

hrm, okay

@crteal this is your problem https://github.com/reagent-project/reagent/issues/296

looks like it, thank you @anmonteiro!

newbie question: are source maps supported by vanilla Node.js repl? I have source-map-support in node_modules but I see:

cljs.user=> (ffirst 1)
repl:13
throw e__7439__auto__;
^

Error: 1 is not ISeqable
    at Object.cljs$core$seq [as seq] (/home/arichiardi/git/logpoc/out/out/cljs/core.cljs:1209:20)
    at Object.cljs$core$first [as first] (/home/arichiardi/git/logpoc/out/out/cljs/core.cljs:1218:15)
    at cljs$core$ffirst (/home/arichiardi/git/logpoc/out/out/cljs/core.cljs:1730:10)
    at repl:1:34
    at repl:9:3
    at repl:14:4
    at ContextifyScript.Script.runInThisContext (vm.js:44:33)
    at Object.runInThisContext (vm.js:116:38)
    at Domain.<anonymous> ([stdin]:50:34)
    at Domain.run (domain.js:242:14)

it is source mapped no? I don’t think it supports showing the actual source excerpt but the stack looks mapped?

does it show the correct source excerpt outside the repl?

@thheller oh, well sorry, I tried before this and it was showing .js files in there, then apparently I did something and now they are mapped

for the (lossy) records with no source-map-support it was:

ClojureScript Node.js REPL server listening on 56975
Watch compilation log available at: out/watch.log
To quit, type: :cljs/quit
cljs.user=> (ffirst 1)
repl:13
throw e__7439__auto__;
^

Error: 1 is not ISeqable
    at Object.cljs$core$seq [as seq] (/home/arichiardi/git/logpoc/out/out/cljs/core.js:4414:8)
    at Object.cljs$core$first [as first] (/home/arichiardi/git/logpoc/out/out/cljs/core.js:4433:19)
    at cljs$core$ffirst (/home/arichiardi/git/logpoc/out/out/cljs/core.js:5859:34)
    at repl:1:96
    at repl:9:3
    at repl:14:4
    at ContextifyScript.Script.runInThisContext (vm.js:44:33)
    at Object.runInThisContext (vm.js:116:38)
    at Domain.<anonymous> ([stdin]:50:34)
    at Domain.run (domain.js:242:14)

when calling get on a map in clojurescript 1.9.671 i get the following error and i'm stumped... any thoughts?

(get {:test "one"} :test)

Uncaught Error: No protocol method ICollection.-conj defined for type cljs.core/Keyword: :test

hmmm, a lein clean seems to have fixed it, nevermind 🙂

re :optimizations :none closure still needs to be called for the namespace stuff I think

What's a good way of dealing with eval timeout errors? Both in terms of debugging and catching

I have an expression that works in Javascript using web3 and BigNumber but hangs in Clojurescript when significant digits are above a certain limit

@oskarth what do you mean - there’s not really a way to deal with that in JavaScript either - do you mean just at the REPL?

@dnolen yes

that’s a REPL specific feature - I don’t think there’s a general way to provide that

Specifically, this works: (.fromWei js/Web3.prototype 111122223333440000 "ether") but this hangs: (.fromWei js/Web3.prototype 111122223333444000 "ether") (treating numbers as strings causes the same behavior) whereas both equivalent forms work in a JS repl: web3.fromWei(111122223333440000, 'ether') web3.fromWei(111122223333444000, 'ether') - trying to figure out why or deal with it somehow

@oskarth I’m confused since the CLJS isn’t equivalent to the JS, why aren’t you just writing the same thing?

@dnolen how are they different you mean?

not how are they different

they are different

for what reason?

web3.fromWei(111122223333444000, 'ether') -> (.fromWei js/web3 111122223333444000 "ether")

right, sorry, looking into why js/web3 isn't available

by your initial example it would be js/Web3

same there, in that case why .fromWei isn't

(looks like there's a version mismatch, but can't quite figure out which version is being called and why they differ)

Web3.prototype.fromWei(111122223333444000, "ether") works

@oskarth Web3.js docs show that you should initialize web3 using Web3 constructor yourself:

(def web3 (js/Web3. provider?))
(.fromWei web3 111122223333444000, "ether")

@oskarth https://github.com/ethereum/web3.js/#migration-0130---0140

@juhoteperi tried that, hangs

as far as I can tell they are just aliased, the implementation for this specific function hasn't changed. With one less significant digit it works fine

i’m curious wrt the new 1.9.854 changes in npm-deps and global exports for foreign libs - this doesn’t avoid the need of externs files, right?

in reagent/react/om, we provide "trees", the system then diffs then and modifies the dom; are there libraries for modifying the dom directly?

(most: dommy, domina, seems 2+ years old)

are there any actively maintained ones ?

@qqq i wouldnt be so afraid of “unmaintained” libs.. in a lot of use cases that’s actually a good sign. the dom access api doesnt change all that frequently, for example. so the fact that domina is 2+ years unchanged means it hasn’t had any issues serving its purpose

it’s a strange feeling, I know. it took getting used to, coming from the js-ecosystem, where if something hasnt had changes in 2+ months feels like a “risky investment”

@lwhorton : yeah, with node.js, if the new package isn't somehow incompatible with your existing packages, something's wrong

i attribute this to the mature java ecosystem where people dont investigate a mvn dep and say “hey why hasnt com.goog.array been updated in 5 years?!“.. *and hopefully some of that is rubbing off on the js world

has anyone had any luck with spinning up a docker container with lein fighweel && lein garden auto` concurrently running? Everything I’ve tried so far results in either a subprocess immediately failing or an out of memory error in the container.

is there a thin cljs wraper over google closure? I was just looking at my dependencies, and it seems like google closure provides alot of them

google closure is huge so there might be wrappers for some of it but probably not everything

it's also auto included in every cljs project right?

you can use most of the stuff directly too, so no wrapper needed really

yes

so if it's there, and it's good enough for goog, I might as well as use it

indeed

I'm trying to simplify my cljs dependencies. Do I need weasel + piggieback if I don't need a cljs-repl ?

@qqq no

What’s a good, free service for hosting hobby projects in Clojure/Clojurescript?

heroku makes it pretty easy, or any free tier service that gives you enough RAM to run your project

I've run my hobby projects on Heroku

cheers 🙂

you can make a standalone project with lein uberjar and that should run on any host with a jvm and enough RAM

I’ll give Heroku another go.

Yeah, +1 for heroku.

I've built a test JS file using lein cljsbuild once, and then I try to run it (using node), but I get import errors since a dep is using ES6, so I run it through babel with es2015 presets and then try to run it again. Now, I just see Cannot use 'in' operator to search for 'doo' in undefined

I have :target :nodejs, of course. What else might I be missing?

@reefersleep "another" makes it sound like you've already tried Heroku. Did you have problems or something I can help with?

If I comment out the require for that ES6 code and thus avoid all the babel business, I end up getting __DEV__ is not defined while running lein cljsbuild test. Seems like I hit a wall either way.

@codefinger I didn't, I just never really put an effort into establishing a comfortable relationship with Heroku, and thought I'd ask around to see if there were other, possibly better options 🙂

I have managed to get something up and running.

Hah... two years ago. Damn! https://derpanet.herokuapp.com/

@reefersleep Google Cloud offers 300$ of free credits (usable over 12 months)

It’s not a PaaS like Heroku though, so you would have to get your hands dirty

Heroku is great as a free option, and has amazing UX, but for hobby/non-profit projects that need more than their free dyno it’s prohibitively expensive. I am working on a couple of non-profit projects at the moment and I am experimenting with Kubernetes on Google Cloud. One of the neat things you can do is schedule some of your services on preemptible instances (which cost something like 30% of the full price, in exchange of the possiblity of them being shut down at any time)

I have heard of https://deis.com/workflow/ but haven’t tried it yet

There is also http://dokku.viewdocs.io/dokku/ ; it was too limited for my use-case but it might interest you

Recently I also stumbled upon https://hyper.sh/ (no idea how reliable they are though)

And https://zeit.co/now (which I found a bit dodgy but some people like it)

I've had a pretty bad experience with Clojure on GAE. From no Clojure tooling support to memory leaks in their infrastructure and dead end support for fixing existing issues.

Heroku was a breath of fresh air, compared to App Engine.

I prefer to set up a deployment where nothing on the server even needs to know you have clojure in your deploy - making an uberjar, with a shim to some runner lib if needed

In theory, sure. In practice, it's very nice to have a lein plugin for your hosting service so you can easily deploy, troubleshoot, etc.

I never use lein on prod

(this is with years of full time clojure dev)

Use a CI pipeline to build the uberjar and push to your prod infra @jeaye

For my current project I have a CI job which builds an uberjar, packages it in a Docker image and pushes that to a repository

which is then pulled and ran in K8s (google container engine)

I don't think that changes anythying, @hmaurer, and I don't think anything I've said has implied such a CI pipeline isn't in place.

I mean, you were mentioning “easy deployments”

The point is, deploying, from wherever can be quite simple with a lein plugin. Like how Heroku does it.

Painful deployments from a CI server are still painful.

Why would deployments from a CI server be painful?

@jeaye my rationale for not using any clojure tooling on my deploy target is to increase my choices and flexibility in deploy targets, it requires a bit of glue with CI and/or automated deploy tooling

but then all I need is a jvm, which is an easy bar to reach

I am a noob, but that’s one of the things I like the most about the JVM. I can just ship a jar to production and run java -jar ... with a few options. No need to worry about installing the correct dependencies etc

I can even run that jar locally to check everything works

@hmaurer With App Engine, a deployment requires building an uberwar, exploding it, replacing some files, and using a supplied GAE script to repackage it.

If you haven't used App Engine, you wouldn't know it doesn't just use uberjars. 🙂

@jeaye ah, that does sound painful. I haven’t used App Engine

It seems more like a problem with App Engine though

but its still just an artifact

I know because the most up-to-date documentation on getting Clojure working with App Engine is right here: https://blog.jeaye.com/2016/08/23/clojure-app-engine/

It's a mess.

With heroku, it's lein do ring uberjar, heroku deploy

cheers @hmaurer 🙂

or in a Procfile

web: java -server $JVM_OPTS -jar target/myapp-standalone.jar host 0.0.0.0 port $PORT

-server is optional and could even be provided in JVM_OPTS instead

that way, your CI/CD can handle deploys instead of manual deploys

which I prefer

Recently ran into https://circleci.com/blog/deploying-clojure-applications-to-google-cloud/ which skips some of what you’ve done by leaning on Docker

It'd be interesting to have one of the Google Closure compiler developers to give a talk at a clojure event.

@jakemcc Relying on App Engine Flexible forfeits all of the benefits of App Engine's "serverless," automatic environments. It also forfeits the support that Google would be required to give you for the stability of that environment, since now you're running your own.

Hi, as of today I'm no longer able to run lein uberjar for my app, it returns this error: NoSuchMethodError: com.google.common.base.CharMatcher.javaUpperCase()Lcom/google/common/base/CharMatcher; I gather this is a guava conflict (not sure why, didn't add any new dependencies). Any suggestions on how to troubleshoot this?

@dealy sounds like a case for lein deps :tree, googling where that method is supposed to come from, generous use of :exclusions and hope