luajit VS Laminar

> No offence, but have you written any compilers or interpreters?

I have, but nothing sophisticated.

> The points that you discuss [...] may be performance concerns for application developers [...] but they have very little to do with the optimisations you can make as a compiler/interpreter writer. [...] The only one that's somewhat relevant is 'global scope by default'

I didn't mean to imply that these where the three common traits that make both Javascript and Lua particularly hard to optimize, I just picked them as examples for how Javascript and Lua are closer to each other than most other dynamic languages.

But let's dig in a bit on your claim that things like all numbers being doubles or having a array cum map cum record type has very little to do with the optimizations you can make as a compiler/interpreter writer, because it sure seems to me that LuaJIT and V8 do a bunch of optimizations around these things. Both have dual number representations under the hood and will try to avoid representing numbers that remain in the domain of 32 bit integers as double values internally when that gives performance gains. The logic for figuring out if that's the case doesn't seem to be super-straightforward or target architecture independent from looking at the comments in <https://github.com/LuaDist/luajit/blob/master/src/lj_opt_nar...>.

LuaJIT furthermore uses NaN tagging (as do some JS engines, although not V8), which looks less attractive to me as a representation strategy if your numbers are not all/mostly notional doubles (as is indeed the case in newer version of Lua where 64bit integers are the dominant number type)

Also, as far as the super-flexible lua tables are concerned, I'm pretty sure LuaJIT goes through some amount of trouble to specialize various common use cases of tables, e.g. as arrays without holes, and surprise, so does V8 (https://v8.dev/blog/fast-properties#elements-or-array-indexe...). I don't think you'd find something equivalent in a high performance scheme implementation.

> but this doesn't touch the surface of the issues that make JS hard to optimise, such as the fact that your, say, memoisation of an object property or method may be broken by an `eval` call of an arbitrary runtime value somewhere else in the code (which, due to asynchronicity, could take place at more or less any time from the point of view of your given 'peephole').

Eval belongs to a core set of features that basically all popular dynamic languages share that presents headaches for high performance implementations. How is Javascript's eval particularly problematic in this regard, and specifically much more so than Lua's loadstring/load?

More generally what do you think makes (pre-ES6) javascript significantly harder to optimize than lua 5.0?

My quite niche open source project broke this threshold last year, via Github sponsorships. Of course, I put a lot of time into it, so it's not "passive income" or even "market rate income", but still, without these sponsorships I wouldn't be able to work on it so much.

The project is Laminar, a UI library for Scala.js https://laminar.dev

I've noticed that Laminar and the newly released Kyo point that they don't use a lot of macros as a feature. Laminar says "Easy to understand: no macros", while Kyo emphasizes "Note: defer is currently the only macro in Kyo. All other features use regular language constructs." It seems that using less macros is something library users will like.

https://laminar.dev/ might be what you need. Though I wish there was a more beginner friendly (I'm not from front-end world) tutorial for me to follow along.

Have you looked at Laminar and Tyrian? Especially Tyrian seems to be close to what you're looking for.

For Scala there is Laminar, which has an even flashier website with nice docs. I haven't tested it out though, as I have never used Scala.

I found this scala library called Laminar which looks super similar to solid. They use signals and has no virtual dom. State changes are represented by signals and events by event streams. Thus they seems to have feature parity with RXJS as they can model all sorts of async stuff. Best part is they get to keep writing their markup in C-style syntax than XML based JSX. It looks super elegant,minimalist and has type safety.

This is very true. I really hate svelte single file components. But then I tried JSX for breaking things down. I love solid but I don't feel really good about angle brackets within C style syntax. I saw this Scala library that stick with simple statically typed function syntax than html tags. I don't understand why people still wants to stick with xml like tags. In laminar markup is written like this scala div( h1("Hello world", color := "red"), inputCaption, input(inputMods, name := "fullName"), div( ">>", button("Submit"), "<<" ) ) I wish solid team makes their HyperScript syntax as performant as JSX.

Laminar (Scala framework) hasn't been mentioned yet so dropping it here as an awesome framework that support HTML-over-the-wire. It can be used together with React, HTMX, and many other frontend frameworks -- but doesn't have to be.

https://laminar.dev/

Scala.js core itself, which I maintain, does not need much innovation. We support all of Scala, and interact with any JavaScript library. That's what the core promises.

If you want to compare to Scala 3, it's worth pointing out that you can use Scala.js with any Scala version >= 2.12.2. In particular, you can use it with Scala 3 and benefit from all its innovations. ;)

Innovation comes mainly from libraries, notably UI libraries. Laminar (https://laminar.dev/) is a great example.

In terms of roadmap, we are mostly working on "boring" stuff: improving performance (of the generated code, and of the linker), fixing bugs when they get reported, etc.

Perhaps, when Wasm gets more features for deeper interoperability with JavaScript (manipulating objects notably), we will take another look at targeting Wasm. People usually expect all languages to target Wasm now, "because it's fast". Truth is, it's fast for languages with linear memory. There is no evidence yet that it will be fast for memory-managed languages with objects and virtual dispatch.