ok, so i got this far https://github.com/cljsjs/packages/blob/a486e6af0389a1d2754e3a21e7772f082b208815/react-virtualized/build.boot#L23-L36

i should write something like this, for jsnetworkx

probably easier than reimplementing the algorithm, although i am not quite sure, that formula doesn't look this complicated 😄

what is the best way in clojurescript to extend ES6 classes? I want to extend code like in this example: https://github.com/substance/simple-writer/blob/develop/lib/simple-writer/SimpleWriter.js#L9

@podviaznikov not sure if there is a better way but I just do it manually … stole it from one of the many react libraries (probably om ;p)

(defn ^{:jsdoc ["@constructor"]} Root []
             (this-as this
               (.apply js/React.Component this (js-arguments))
               this))

           (set! (.-prototype Root)
                 (goog.object/clone js/React.Component.prototype))

(specify! (.-prototype Root) Object … your stuff …)

thank you @hueyp!

I tried to cache canvas data by caching the dataURL. Turns out redrawing the canvas is like 50x faster than creating an image from the dataURL. Does that make sense?

yes

@ashnur good

but it also depends on a bunch of factors, however i expect canvas to be extremely fast by itself

it depends on the amount of operations on the canvas vs the amount of data generated by the canvas I guess

my first guesses for why the dataURL method might be slower are 1. conversion might be hard 2. some DOM API might be touched and that obviously ruins everything immediately

@ashnur do you mean the creation of a new image element as DOM api?

that would be one example, sure

Is there already a macro that wraps (js/performance.now) around the body and prints the duration of an expression that I don’t know of maybe? 🙂

(defmacro profile-always
  "Stays in production"
  [k & body]
  `(let [k# ~k
         t0# (js/performance.now)]
     (let [res# (do ~@body)
           t1# (js/performance.now)
           ms# (- t1# t0#)
           report# (str k# " " ms# "ms")]
       (if (< 10 ms#)
         (js/console.warn report#)
         (js/console.info report#))
       res#)))

there is cljs.core/system-time, btw

@rauh something like that yes 🙂

Can a macro re-definition be picked up by the clojurescript compiler?

or is it only read at startup?

@borkdude we have support for :reload at the REPL, downstream tooling can easily support macro-redef

also the time macro calls performance.now if available

nice, thanks!

Made this one now:

(defmacro profile-js [k & body]
     `(do
       (defonce ~'profile-stats (atom {}))
       (let [k# ~k
             t0# (js/performance.now)
             res# (do ~@body)
             t1# (js/performance.now)
             ms# (- t1# t0#)
             all-stats# (swap! ~'profile-stats
                                update k# conj ms#)
             k-stats# (get all-stats# k#)
             avg# (/ (apply + k-stats#)
                      (count k-stats#))
             report# (str k# " " ms#
                          "ms, average: " avg# "ms")]
         (js/console.info report#)           
         res#)))

example output: https://www.dropbox.com/s/chp01s6df6jvax3/Screenshot%202016-12-13%2013.46.06.png?dl=0

@dnolen About yesterdays conversation: This also means we should avoid declare for performance critical code since the cljs compiler won't know the exact arity of the function and generate unoptimal code. Good to keep an eye out.

Hi

import createRichButtonsPlugin from 'draft-js-richbuttons-plugin';

const richButtonsPlugin = createRichButtonsPlugin();

Given that, what would the clojurescript version be?

(defn createRichButtonsPlugin (aget js/window “createRichButtonsPlugin”))

Trying to use, https://github.com/jasonphillips/draft-js-richbuttons-plugin#usage

@crankyadmin

(def createRichButtonsPlugin (. js/window -createRichButtonsPlugin))

@anmonteiro you the man!

aget is meant to only be used for arrays

I’m ashamed… I knew that.

Its been a head bashing off desk morning.

that wasn't the problem with the above though. It would work (currently), but that's an internal implementation detail

your problem was the defn

I get a esModule back now. Which is a step forward. 🙂 My main problem is that I’m having difficulty porting this https://github.com/jasonphillips/draft-js-richbuttons-plugin#usage to cljs

I just want the CodeButton object

oh

@crankyadmin hrm there should be a default key in the object you get, probably

so

(def createRichButtonsPlugin (.. js/window -createRichButtonsPlugin -default))

^ maybe

(def richButtonsPlugin ((.. js/window -createRichButtonsPlugin -default)))
(def CodeButton (aget richButtonsPlugin “CodeButton”))

@rauh we always generate arity check + dispatch if we can’t figure it out - but yes declare is like the higher order case

How can I clone and install the google-closure-library local? I found a bug and wan't to resolve it for my project.

@danielgrosse afaik @stuartsierra is packaging that for Maven etc, maybe he has some advice or repo up somewhere

in the clojurescript repo there is a script under /script/closure-library-release

that’s the script used to build the lib that clojurescript depends on so you could modify that

@alexmiller Thank you. I will look into it.

Hi, why the (for ...) clause in the let clause did not run? I logged the value of k and v but it shows nothing.

the console output is {:title "test1" :options {"a" 0, "b 2}} 2 0 -1 ["#1f77b4", ...]

@cmal for is lazy, you probably want a doseq in this case

@rauh oh, Thank you!

@danielgrosse you can also just put the file you want to edit into your source path

that should take precedence over the file in the jar

I'm trying to use a js package in my cljs app, the js package add the object A to window. How can i require the A object using cljs ?

@lxsameer: people generally do this via :foreign-libs compiler option

I'm using the samething

I'm trying to use Grommet

it has a global object which contains several react components. What is the best practice to use the children of the Grommet object ?

@dnolen since intern in not implemented in cljs, how can i define a var from a string ? something like (intern ns (symbol "x") value)

there’s no such thing since Vars do not really exist

reified vars and namespaces are pretty much incompatible with the advanced compilation model

the answer to Var & Namespace voodoo in ClojureScript is - "no you can’t do that"

@dnolen thanks that was the best answer 🙂

@lxsameer we can simulate only the static aspect of vars, like dump the metadata for a var - but all the dynamic stuff is not possible

hiya, I'm trying to debug some spec code that often throws an error on cljs:

the trigger seems to be that the second form's :max-count is higher than the first ones

@enajski I don’t see anything obvious, I would use source maps and use a debugger to see where it’s failing in cljs.spec/coll-prob

@dnolen that's where I'm at, will keep hacking at it

@enajski also need more environmental information

I took a look and I see nothing wrong there

newbie clojurescript questions here. I am using material-UI from cljsjs in my project. How do i use it? For example, how would i use the App Bar component http://www.material-ui.com/#/components/app-bar

@dnolen what environment information would be useful? I'm connected to a figwheel/cljs-repl and evaling the code

@enajski that’s useful 🙂

🙂

in anycase I would look at the source for coll-prob I don’t see how you could get that error

you’re as likely to find the source of the problem as I am

I took a cursory look and I didn’t see anything

yup, it's really not obvious why this happens as the clj implementation looks very much alike and no errors occur

@enajski I also couldn’t reproduce your problem at the REPL

have you tried a couple of times? the error occurs with some probablity for me

@enajski I cannot repro

I just tried dotimes 1e5

but I’m not using Figwheel either, just the standard Node REPL

I would not rule out environmental problems

thanks, I'll see what else I can find

so the stacktrace I posted was from Chrome, trying the same in Firefox yields a different message:

ok yeah that helps 🙂

in Safari: #object[TypeError TypeError: undefined is not an object (evaluating 'cljs.core.unquote.call')]

@enajski I pushed a fix to master - if you can try that out

Git clone ClojureScript, cd into the directory, ./script/build

take note of the version that gets installed into your local Maven, and use that in your project instead

(make sure to clean your build, etc.)

will do

thanks much

@dnolen I think it did the trick, thanks!

@enajski glad to hear it

I can't seem to find a function for finding the floor, ceiling and raising a number to an exponent, do people just use js/Math?

Yes.

theres a goog.math.safeFloor and goog.math.log10Floor and goog.math.safeCeil… https://github.com/google/closure-library/blob/master/closure/goog/math/math.js