weird edge case I just found: I had a .cljc namespace which used defmacro, but did not include a (:require-macros [...self...]) in the ns form. this was in a utility library I used in Maria. Whenever I would compile the ‘browser’ build and the ‘bootstrap’ build together, this still worked as expected, so I had no idea I had even made a mistake. But if I would compile the ‘browser’ build independently from the ‘bootstrap’ build, I wouldn’t get a warning, but cljs would treat the defmacro as a function and return the unevaluated form.

It only showed up when I split these builds for circleci (I’m using tools.deps now, and that increases memory usage, so I can’t compile all the builds in one step anymore)

why does tools.deps increase memory usage?

no idea

the good news is that you get a proper exception on circle when it fails

ah right you limited the memory via jvm-opts. those are probably not yet passed onto tools.deps

I don't know about the defmacro thing. one build should not affect the other since they are completely isolated

[:bootstrap] Compiling ...[:live] Compiling ...[:trusted] Compiling ...


/usr/local/bin/clojure: line 342:   316 Killed                  "$JAVA_CMD" "${jvm_cache_opts[@]}" "${jvm_opts[@]}" -classpath "$cp" clojure.main "${main_cache_opts[@]}" "$@"
Exited with code 137

Hint: Exit code 137 typically means the process is killed because it was running out of memory
Hint: Check if you can optimize the memory usage in your app
Hint: Max memory usage of this container is 4287946752
 according to /sys/fs/cgroup/memory/memory.max_usage_in_bytes

I really have no idea, but I could reproduce it

locally and on the server

after I finally figured out what was happening

well they do share the same clojure vm instance. so if one defines a var the other can see it

but both builds should always check if the defmacro is properly required

defmacro in .cljc files without being hidden in a conditional is scarily common

ah right ... the warning does only check if the var exists

but the var exists

the macro is in util, a cljc file, and I was requiring it from another cljc file

so it doesn't warn

so basically macros in cljc files should always be in a #?(:clj …)

so if you (util/the-thing ...) it just calls it as a function

yes, unless you care about self-host in which case I don't have an easy answer for oyu

i think that’s fine with self host?

no self host reads .cljc files with :cljs

oh, right.

macrovich is probably the answer

not really. same problem.

(defmacro deftime
  "This block will only be evaluated at the correct time for macro definition, at other times its content
   are removed.
   For Clojure it always behaves like a `do` block.
   For Clojurescript/JVM the block is only visible to Clojure.
   For self-hosted Clojurescript the block is only visible when defining macros in the pseudo-namespace."
  [& body]
  (when #?(:clj (not (:ns &env)) :cljs (re-matches #".*\$macros" (name (ns-name *ns*))))
    `(do [email protected])))

would that not work?

ah right. its not doing this via read-cond

so yes that works

incidentally this util macro itself uses macrovich, to use keyword-identical? for cljs and identical? for clj

does your build actually work when running both builds? or does it just not complain?

it works

expands the macro

ah right thats the cljs compiler doing that

https://dev.clojure.org/jira/browse/CLJS-2454

I don't think I can do anything here

I don't know if you meant to call a fn or a macro when doing (util/the-thing ...)

the var exists because defmacro creates it

I can probably complain when you defmacro in cljs though

thats just never correct

except in self-host?

hmm right

well I can just ignore it when compiling normal cljs

I mean just don't compile it. so you'd at least get a undeclared var warning

right

because you know when you are compiling normal cljs vs. bootstrapped-macro-mode

exactly

------ WARNING #1 --------------------------------------------------------------
 File: C:\Users\thheller\code\shadow-cljs\src\dev\demo\browser.cljs:24:2
--------------------------------------------------------------------------------
  21 | (defmacro dummy-macro [& body]
  22 |   (prn :foo))
  23 | 
  24 | (dummy-macro 1 2 3)
--------^-----------------------------------------------------------------------
 Use of undeclared Var demo.browser/dummy-macro
--------------------------------------------------------------------------------

makes sense I guess although the warning is a little bit weird since the defmacro is right there 😛

kinda weird CLJS doesn't already do this by default

yeah that looks good

would have saved me a couple hours of debugging

it’s the non-locality that made it so weird. not requiring a clj namespace in one part of the project suddenly means that a cljs namespace somewhere else treats a macro like a function

yeah it is definitely a weird issue. I blame https://dev.clojure.org/jira/browse/CLJS-2454 for not properly checking if macros are actually referred and blindly using them. defmacro is also to blame though.

yes i added a vote to that issue

I wonder if there a legit reasons for keeping the defmacro but I can't think of any

@mhuebert just pushed [email protected]. it probably breaks all the self-host stuff. please test.

ok

I mean it shouldn't break anything but self-host has proven me wrong more than once

anything in particular to look out for?

compile warnings I guess

all looks good

just the usual:

------ WARNING #1 --------------------------------------------------------------
 File: cljs/spec/test/alpha$macros.cljc:113:35
--------------------------------------------------------------------------------
 110 |   ([xs]
 111 |    `(instrument ~xs nil))
 112 |   ([sym-or-syms opts]
 113 |    (let [syms (sym-or-syms->syms (eval sym-or-syms))
-----------------------------------------^--------------------------------------
 Use of undeclared Var cljs.spec.test.alpha$macros/eval
--------------------------------------------------------------------------------
 114 |          opts-sym (gensym "opts")]
 115 |      `(let [~opts-sym ~opts]
 116 |         (reduce
 117 |           (fn [ret# [_# f#]]
---------------------------------------

can they not declare that?

is that a known issue? I mean this doesn't work right?

they set! eval later

is what is said on a slack log somewhere

no idea what that means

can't find where eval is set!

@thheller gotcha

@fbielejec I think cider-jack-in starts a new lein process, so it won't find the one started by shadow-cljs watch

you can instead start the embedded version in the cider repl

right, it's equivalent to lein repl basically, starts an nrepl session

so you can do this https://shadow-cljs.github.io/docs/UsersGuide.html#embedded

(require '[shadow.cljs.devtools.server :as server])
(server/start!)
(require '[shadow.cljs.devtools.api :as shadow])
(shadow/watch :foo)
(shadow/nrepl-select :foo)

can I invoke a watcher like this too? e.g.

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

wrote at the same time, nevermind

btw :dev is a built-in concept of shadow-cljs. every build has a dev and release mode

so I better not call the build-id :dev?

you can call it whatever but it doesn't make much sense yes

in figwheel&co you actually have a different build for release

in shadow-cljs its just shadow-cljs release the-build or shadow-cljs watch the-build

gotcha

I need to document this better, I see this a lot 🙂

it's just scattered a bit, but the fact I can get npm packages working out of the box is worth spending some time searching 🙂 It's awesome.

Ok, so I killed the watcher in the terminal, create a user ns with these invocations

shadow-cljs - HTTP server for :app available at 
shadow-cljs - server running at 
[:app] Configuring build.
[:app] Compiling ...
[:app] Build failure:
The required namespace "cljs-0x-connect.dev" is not available.

To quit, type: :cljs/quit
[:selected :app]
mar 14, 2018 12:02:49 PM clojure.tools.logging$eval8628$fn__8631 invoke
WARNING: stale websocket client, no worker for build :dev

but I do get the build served in the browser

no cljs REPL though

did you use :lein true in your shadow-cljs.edn?

the http server is independent of the build

yes, it''s probably a stale version served

yes I have :lein true.

What's curious is that it keeps me in clj REPL

wondering why you get the build failure? did it work when running shadow-cljs watch?

me too, when running the same build using CLI tools it works as expected

source paths maybe

https://github.com/district0x/cljs-0x-connect/blob/master/project.clj

please don't ever clean the .shadow-cljs dir. :clean-targets ^{:protect false} ["target" "public/js" "node_modules" ".shadow-cljs"]

cache actually works in shadow-cljs so there is no reason to do it ever.

gotcha. Ok so the build failure happened because "src" was not in :source-paths ["src" "dev"]

ah

I incorrectly assumed it is handled by the shadow-cljs, since I specify the :source-paths ["src"] there too

as soon as you set :lein :dependencies and :source-paths are managed by lein and no longer mean anything in shadow-cljs.edn

I should really start writing a proper migration guide

ok so very close now:

user> (start-dev!)
mar 14, 2018 12:17:48 PM org.xnio.Xnio <clinit>
INFO: XNIO version 3.3.8.Final
mar 14, 2018 12:17:48 PM org.xnio.nio.NioXnio <clinit>
INFO: XNIO NIO Implementation Version 3.3.8.Final
shadow-cljs - HTTP server for :app available at 
shadow-cljs - server running at 
[:app] Configuring build.
[:app] Compiling ...
[:app] Build completed. (226 files, 124 compiled, 0 warnings, 29,07s)
To quit, type: :cljs/quit
[:selected :app]
user> JS runtime connected.

only problem is I'm kept in clj REPL in the user namespace, no cljs REPL

@mitchelkuijpers has cider experience. I don't really know anything about cider

I think you are supposed to call something from cider to make the switch

but I don't know what

ok I'll experiment with this, probably a middleware problem

many thanks for your time and help!

@fbielejec if you figure it out let me know please. want to finally have something I can put into the docs. 🙂

I will, off course. Btw I notice the same behaviour (no cljs REPL) when just calling lein repl and then starting the server, watcher and repl using the API.

I think you can't purely do this via clojure

something in cider is supposed to clone the session so you have one for clj and one for cljs

you probably mean cider-create-sibling-cljs-repl. That could work, I'll try.

https://markhudnall.com/2016/04/25/starting-figwheel-in-emacs/

just replace figwheel with the shadow-cljs stuff and it should work

@fbielejec did you figure it out?

hey - yes, I'll be writing up a quick how-to post, should be done by evening

Unless it's urgent, then I'll paste the instructions here 🙂

No, we have been working with cider for 2 months now 😛

aaahh ok

then you should be doing the writing I guess 😄

Yes you are completely right

no worries, http://www.blog.nodrama.io/shadow-cljs-cider/ 😛

@fbielejec cool!

is the emacs/cider integration fully functional with a cljs nrepl? i.e., does it allow you to send forms, get documentation strings, do tab completion, find definitions, stuff like that?

@lee.justin.m yes all works

that is the worst news ever: I really do not want to go back to emacs 🙂

hehe

@lee.justin.m fairly certain the same setup should work for Cursive too

probably. i use atom. i tried to get cursive installed and it was super confusing.

i guess cursive would be better than emacs so i should give it another shot

nothing's better than Emacs 😁

expect Cursive

i spent 15 years on emacs and i don’t want to go back

that's the minimum time span one should spend before switching editors 😛. It's really paramount for productiveness imho, whatever the choice might be in the end.

agreed, I spent almost 8 years on Vim before moving to intellij stuff, I used to spend around 10 ~ 20% of my time tweeking my editor, in Intellij I don't have as much customizations, instead I just use it as is mostly (except for snippets and some repl commands) and I'm very happy with not having to configure things all the time

I'm very happy with Cursive for the time being. Never want to back to emacs as well.

It asked if I wanted to index the remote repositories and I said yes. I’m worried i just told cursive to go index everything on maven and clojars.

I honestly don't know what that is about but it eventually finishes 😉

the clojars index in a decent time, the maven can take forever

so do i need to do anything special to get an nrepl to connect to shadow? I put in the localhost/9000 (which is what my nrepl is configured to), it just hangs on `Connecting to remote nREPL server... Clojure 1.9.0`. i confirm that it works if i connect using the terminal.

it doesn't print anything else. you should be connected. just eval something to test

that still doesn’t work.

Connecting to remote nREPL server...
Clojure 1.9.0
(js/console.log "HELLO")
CompilerException java.lang.RuntimeException: No such namespace: js, compiling:(null:1:1) 
(+ 1 1)
CompilerException java.lang.RuntimeException: Unable to resolve symbol: + in this context, compiling:(null:1:1) 

its a clojure repl

no idea about the null though

Connecting to remote nREPL server...
Clojure 1.9.0
(+ 1 2)
=> 3