I have looked semi-carefully for such a thing, and believe there is nothing in ClojureScript like that. Are you hoping to get some reduction in memory usage for large immutable vectors in cljs? Or do you have some other motivation for wanting such a thing?

I am semi-actively working on a replacement for the core.rrb-vector library with hopefully fewer bugs. If someone figures out a use case and an implementation strategy for such a thing in ClojureScript, I could consider adding it to my core.btree-vector library, with a cljs as well as a Clojure/JVM version.

I want fast unboxed operations @U0CMVHBL2 with vector like semantics :)...

I have a reasonably robust test case set if that helps?

@U0CMVHBL2 What do you need? Not sure how helpful I can be =)…

I don't currently know very much about JavaScript runtime engine details. Do they even have a distinction between boxed vs. unboxed numbers, the way JVMs do?

I think there’s a clear difference between working directly with arrays and values

The problem is that in clojure you can still work with arrays using vector-of

you can’t do that in clojurescript

you have to directly use aset style semantics…

The other thing I’ve been thinking of is writing vector-of in cljs by working out how to support the api…

been reading a lot of ztellman’s stuff on how he did it in java.

It would also reduce memory =)… But that’s a bonus

Clojure/Java has the notion of regular vectors, i.e. immutable vectors where every element is an arbitrary object/value, as does ClojureScript. Java has arrays of Object or any JVM primitive type like long/double/etc., as I guess does JavaScript. In Java, arrays of long/double/etc. take significantly less memory than arrays of Object, if those arrays are restricted to contain only long/double/etc.

Are there JavaScript arrays that are restricted to contain only numbers, and cannot contain other types of values as their elements?

And is the way to declare them consistent across different JavaScript runtime engines?

Yes

If so, then introducing vector-of into ClojureScript is certainly possible, and potentially useful to some people. And I would guess could be done as part of a 3rd party library, as it can be done in Clojure/Java.

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Typed_arrays

If you’re aware of this, what’s the way of doing something like this in clojurescript? This sounds like a valid next step =)…

Happy to put together a first pass implementation!

For clojure I’d just have to use deftype I believe and then add methods, I assume it’s the same in cljs?

If you want to take a crack at it (sounds like you would get to it before I would), I would recommend reading the Clojure/Java implementation of vector-of in the file src/clj/clojure/gvec.clj of the https://github.com/clojure/clojure code, and ask questions if you have them -- happy to tell you what I know about it. I am not currently much help with ClojureScript/JavaScript interop details, as I haven't done that before.

Sure, thanks!

Folks in the #clojurescript and/or #cljs-dev channels would be more knowledgeable on the ClojureScript/JavaScript interop than I, if you get stuck on that.

OK, heading to bed right now, so incommunicado for some number of hours starting now -- not ignoring you 🙂

It's right there, in the Keyboard component documentation, before the description of the setInput method that you're using: https://franciscohodge.com/projects/react-simple-keyboard/documentation/#methods

@U2FRKM4TW - Sorry, did not quite get you. Before the description of setInput , there is a getInput method being described. Actually , I have a working React JSX code for the same, which I am trying to convert to Clojurescript. How would I get a reference to the Keyboard in cljs ? Once, I have a reference, I could probably invoke whatever methods are supported on it. Thanks.

The code block right after the sentence "To access these functions, you need to get the instance of simple-keyboard, like so" in the documentation:

<Keyboard
  keyboardRef={r => this.keyboard = r}
  [...]
/>

// Then, on componentDidMount ..
this.keyboard.methodName(params);

BTW in Reagent, you can specify such keys either as :keyboardRef or :keyboard-ref - both ways works.

Thank you so much ! Its working . Have replaced the incorrect property name ref with keyboardRef

Verbatim:

(def use-styles
  (makeStyles
    (fn [theme]
      #js {:paper #js {:marginTop     (. theme (spacing 8))
                       :display       "flex"
                       :flexDirection "column"
                       :alignItems    "center"}})))

oh thank you!

what's the #js ?

https://cljs.github.io/api/syntax/js-literal

alright. thank you

I'm sorry to bother you but can you tell me what's wrong in this code?

(def use-styles
  (makeStyles
   (fn [theme]
	 #js {:paper #js
		  {:backgroundColor "blue"}})))

(defnc main-layout [{:keys [children]}]
  (let [[classes] (use-styles)]
	[mui/Container {:component "main" :maxWidth "xs"}
	 [mui/CssBaseline]

	 [:div {:className (. classes main)} "lets see if it works"
	  children]
	 ]))

Let me guess - it throws an error about not being able to use hooks within class components?

actually no.. I think the use is wrong

I get this: nth not supported on this type function Object() { [native code] }

I'm using hx and not reagnet

Ah, right - just noticed the defnc.

I think the problem is in this line:

(let [[classes] (use-styles)]

(let [[classes] (use-styles)] ...) - why do you destructure the result of (use-styles)?

I'll show you

Just use (let [classes (use-styles)] ...).

okay okay

I'll try that

this is the equivalent code in js:

export default function SignUp() {
  const classes = useStyles();

  return (
    <Container component="main" maxWidth="xs">
      <CssBaseline />
      <div className={classes.paper}>
        <Avatar className={classes.avatar}>
          <LockOutlinedIcon />
        </Avatar>

Yeah, and there's no destructuring.

BTW you also use (. classes main). It should be (. classes -main).

oh yeah!

it's working!

wow thank you

what's the - ?

and why sometimes I see it using the other way around? like (.-main classes) ?

(.main classes) calls the function stored in the main field of the JS object classes. (.-main classes) just returns the field's value.

got it! thanks for the clearification

(. x y) and (.y x) are equivalent. Same for (. x -y) and (.-y x).

thank you so much for your help!

got it.

I wish there was a clojure way to this one

I mean the use-styles. I'll try to create a macro for it

What would it simplify?

the weird #`js`

and I guess the (. classes -main) interop

Sounds good.

also the anonymous function

yeah I'll try haha

Just make sure you're not calling clj->js and js->clj all over the place, except for during macro expansion. Maybe this will be of use, especially for turning (. classes -main) into something like (:main classes): https://github.com/mfikes/cljs-bean

Yes sir. thank you for your time.

what's this cljs-bean?

Exactly what it says in its description. :) It's faster than doing clj->js in the cases when it can be used at all.

oh got it

Thank you

Would you prefer something else? This looks OK to me!

Making assoc mutable is gross/wrong

As probably extending the built-in types. At least, I've seen multiple people say that it shouldn't be done.

Well perhaps, I’m trying to get vector-of like semantics… So basically wrapping primitives, which is available in clojure, but not clojurescript… @U050ECB92, I’m not saying this is great, but trying to write cljc compatible code is really frustrating as cljs-core does not support this even though clj-core does… I’m not finding much stuff around working with primitives without dropping down to raw-arrays…

Your rationale doesn’t hold water

assoc is about persistent data structures

Then why does it work on vector-of with primitives?

Because vector-of isn’t raw primitives, but a persistent map implemented over arrays

In other words the impl follows the contract

assoc returns a new vector

Fair enough, irrespectively, I’m treating these as persistent in my code. Part of this is trying to bring the clojurescript side of my code in line performance wise with the clojure side… I wrote my algo with vectors, now I’m trying to make it more performant, and I don’t know how to write persistent datastructures…

And as this is presently missing, I’m trying to improve things while this is missing…

I can’t do much until this get’s implemented in core, or someone who knows what they’re doing writes a lib, until then I’ll have to do this sort of thing…

I mean if you have a thing that you can point to that isn’t just lots of java or javascript that I can look at to work out how to do this great! I’ll use that instead…

But until then I’d rather get code working until the situation becomes better, instead of throw up my hands and give up until someone writes it…

yeah if you’re treating it persistently that’s cool. I had to pipe up bc no one else was questioning whether this was a compatible impl with assoc

It’s not really adding any value over aset either

Well it is because aset doesn’t return the structure

it returns the value added

Like I said, not much value :)

Could be a function

so I can’t treat it like it’s a normal datastructure

right, but now we’re getting into writing custom functions as opposed to being able to treat it like a seq

It is a mutable object, and shouldn’t be given operations that don’t comply

seq is for values

fair, and I’d like to wrap it so it is immutable.

but there’s no other easy way do get fast primitive math that I’ve found so far

vector-of in clojure land makes this really lovely

it doesn’t exist here, so I’m trying to put something together which gives me similar semantics…

Does vector-of not exist in cljs?

nope

My ns is called vector-of

because it’s not there…

otherwise I’d use it, no question!

I see. Maybe you could steal the impl of PV in clojurescript but put typed arrays at the bottom?

where is that?

I’ve been digging into the internals, but I’m still really unfamiliar with stuff at this level, usually I’m writing application level code =)…

https://github.com/clojure/clojurescript/blob/master/src/main/cljs/cljs/core.cljs#L5336

Starts there

It’s a bit to digest, but there is a core deftype a little bit lower down

would this be a case of create a new deftype similar to PersistentVector? and then do a similar thing?

Yeah, you don’t have to impl all the protocols

These look really similar to the protocols I’ve been implementing

But the ones you do implement must comply with the protocols in spirit

AKA assoc can’t mutate same vector, must return new vector

Yep, that’s fair

I’m trying to work out how far down I need to go…

probably to line 6164 by the looks of it…

great, let’s give that a go =)… Thanks @U050ECB92

😇

There was a clojure library called hiphip that does operations on arrays

https://github.com/plumatic/hiphip

Ok, that’s interesting

I’ll try and get stuff on par with vector-of first =)…

Did you just try transients instead of array for performance?

I haven't no, not really familiar with how to use them...

I mean they'd only speed up inserts and updates to a vector. If what you want is to store primitive values in a vector that's different

Well I’m trying to do unboxed primitive math fast.

Ya, never mind then. I thought you were switching to arrays for faster inserts/updates. It won't help for primitive

No problem =)… Always glad for a helping hand ;)…