elm-spa-example VS gc

About 7 years ago, in the midst of writing Elm in Action, Richard Feldman developed rtfeldman/elm-spa-example, wrote Tour of an Open-Source Elm SPA and graciously shared both of them with the Elm community. The community's response was overwhelmingly positive and it was clear that he had addressed a major need. If you were one of the many web application developers asking "Where can I find an open-source example of an Elm Single Page Application?", then, the Elm SPA Example instantly became the canonical example that everyone was going to point you towards. This was a landmark achievement in the history of Elm.

One accidentally nice thing about that book is the elm version is still the same, so everything is still relevant. As for the SPA, I think the book had to keep things simple, but you'd probably want to look into the author's elm-spa-example next, there's a talk on youtube that goes along with that and he also also a related course on frontend maters worth exploring.

I'm following along with the update behavior of https://github.com/rtfeldman/elm-spa-example/blob/master/src/Main.elm. But I'm not sure how I propagate a message from Main.elm to User.elm to Table.elm (or deeper). How do you manage Msg passing like this?

I am building my first Elm app just following the docs from the official web site. I don't see any direct mention of styling there. Looking around, I see the elm-ui project is one, elm-css is another approach, and the example SPA that Richard Feldman made just uses a stylesheet from Bootstrap, i.e., just plain CSS. If it exists, what's the canonical way of styling an app?

A good example of this is the Elm-SPA example from Feldman: the Main.elm file is basically just glue code for the rest of the project (https://github.com/rtfeldman/elm-spa-example/blob/master/src/Main.elm).

After all that I've managed to reach my goal of being able to run Richard Feldman's Elm SPA Example in my system! 😃 Here's a working implementation compiled to WebAssembly. And for comparison, you can also check out the same code compiled to JavaScript. (Unfortunately the publicly available APIs don't seem to be returning very much data at the moment but there's not much I can do about that!)

Looking at the Real World application I could see that there were better ways to structure my modules using nested TEAs and keeping the Main module as a hub for everything in the app.

If you want to see Elm code, you might look for example projects on GitHub. (https://github.com/rtfeldman/elm-spa-example comes to mind.)

https://github.com/rtfeldman/elm-spa-example is a good example app. I'd also recommend https://codebase.show/projects/realworld in general if you're looking for example apps in various frameworks and languages. I sadly can't share anything from work as it's all private.

- How to properly structure the project. I differentiate between my core utils and the actual gui. Iced states in the documentation that it's inspired by the Elm architecture. So naturally I've read a little bit about the proposed Elm project structure. So I basically end in a structure like this spa example directory recommended by the Elm communicty: Repo

It may take some time for WasmGC to be usable by .NET. Based on the discussions the first version of WasmGC does not have a good way to handle a few .NET specific scenarios, and said scenarios are "post-post-mvp". [0]

My concern, of course, is that there is not much incentive for those features to be added if .NET is the only platform that needs them... at that point having a form of 'include' (to where a specific GC version can just be cached and loaded by another WASM assembly) would be more useful, despite the pain it would create.

[0] - https://github.com/WebAssembly/gc/issues/77

Yes, that's definitely true: a single GC will not be optimal for everything, or even possible. Atm interior pointers are not supported at all, for example, but they are on the roadmap for later:

https://github.com/WebAssembly/gc/blob/main/proposals/gc/Pos...

What launched now is enough WasmGC to support a big and useful set of languages (Java, Kotlin, Dart, OCaml, Scheme), but a lot more work will be required here!

GC proposal is from 2018: https://github.com/WebAssembly/proposals/issues/16 and there’s code: https://github.com/WebAssembly/gc/blob/master/proposals/gc/O...

Seems like an awefully long time for progress to be made, given all the possibilities it would unlock.

First is the size. Writing a server-side and client-side program is possible with Rust, and the resulting WASM package will be small enough. At the same time, Microsoft Blazor converts C# code to WASM, but the client delivery has to include the reduced .NET runtime, taking several megabytes for a script. The same is true for GoLang, even with an attempt to reduce the runtime delivery in TinyGo WASM. Developers want to work with their favorite languages, whether it is Java, Kotlin, Dart, C#, F#, Swift, Ruby, Python, C, C++, GoLang, or Rust. These languages produce groups of runtimes. For example, JVM and .NET have many common parts, Ruby and Python are dynamically interpreted at runtime, and all mentioned depend on automatic garbage collection. For smaller WASM packages, browser vendors can include extended runtime implementations, for example, by delivering a general garbage collector as part of WASM. Garbage collection support by WASM is currently in progress: WASM GC, .NET WASM Notes.

My understanding is that the main limitation is technical. WASM doens't do GC or the host system calling conventions and cannot interact directly with object from Javascript because of this. However, this is being worked[0] on and will be solved eventually. Even without this the performance overhead of bridging to JS is low enough that WASM frameworks can beat out React.

0: https://github.com/WebAssembly/gc/blob/main/proposals/gc/Ove...

I’ve just watched a video on YouTube from Google I/O 2023 on Flutter for the web. Kevin Moore explains that Flutter can compile to Wasm, but now that GC support has been added to the standard and WasmGC is supported in Chromium and Firefox, I’m quite intrigued.

I have found the main thread about using WebAssembly GC in C#: https://github.com/WebAssembly/gc/issues/77. If I understand it correctly, it is not possible to use the current prototype version of GC in C#.

The .net team has given their notes on it, the concern is more on the memory layout from what I remember. Though it may be possible still. The runtime would likely still ship some gc code, but only a subset for cases not supported by the wasm gc itself and a few more for interfacing with the gc service, which overall should still result on smaller payloads compared to current sizes.

I assume that's one of the parts of the work done at https://github.com/WebAssembly/gc - not happening any soon yet, but it'll eventually be done.