reflex VS Elm

FRP solutions sound very attractive. But reflex seems to be stuck on the outdated GHCJS, and I haven't been able to get it to build. The newer JS output in GHC doesn't yet have DOM support. And even if I used one of those, figuring out how to interact with a LaTeX renderer might be tricky.

I only have experience using Reflex, which I regard as the main contender for FRP UI libraries in the Haskell sphere. It's got a flashy website, but I think the documentation is a bit disorganized -- it took a long time for me to figure out how to get going with the library (you find some pieces of knowledge scattered here and there, if you look hard enough). My plan was to learn it well enough to onboard other people, but I don't think I could convince anyone who hasn't already decided that they're gonna make UIs in Haskell no matter the required effort.

Once someone has spent a bunch of time with Haskell and sees the value, they will find Nix if it makes sense. Maybe they'll want to play with https://reflex-frp.org, or they'll discover they want a better way to package 3rd-party dependencies, or they start using NixOS and want to nix all the things, etc. etc. Or, maybe they'll never find a use for it, and that's okay.

Now, I've been convinced to take another look at reflex. This quick reference seems very useful, most other resources seem to always discuss reflex-dom specifically. I'm not really interested in that.

Have a look at https://reflex-frp.org/, or https://owickstrom.github.io/gi-gtk-declarative/, they are an interesting and different way of working with UI in a non imperative way.

At present, here at Typeable we develop frontend in Haskell and use the web framework Reflex and the functional reactive programming (FRP). The source code in Haskell is transpiled into the JavaScript code using GHCJS.

Reflex is the framework that allows creating reactive web applications in Haskell.

Also you’re the Haskell guy no? Found this while reading a Wikipedia article

Hi there! My name is Nikita. At Typeable, we develop frontend for some of our projects using the FRP approach, specifically, its Haskell implementation – reflex web-framework. The resources that offer guidelines for this framework are quite limited, so we decided to fill this gap more or less.

Looking at the number of opened bugs and lack of releases, I wouldn't call it rock solid.

https://github.com/elm/compiler/issues

my favorite frontend lang is elm-lang.org, you should try it out.

> How would a user interface written in a functional language look?

Maybe you're not aware of Elm?

https://elm-lang.org

Elm is really functional, unlike the likes of React that are just partially, kind of functional.

There's an attempt at bringing Elm to the desktop, the Roc language... here's an UI example written in Roc:

https://github.com/roc-lang/roc/blob/main/examples/gui/hello...

If you want to write functional web applications running in the browser the library fmlib_browser might interest you. It allows web applications in the elm style using the much more powerful language ocaml.

Elm (parser source code)

It's more than lack of publicity, stuff like this https://github.com/elm/compiler/issues/1773 adds up. The project looks unmaintained, because it is unmaintained. I guess deliberately so.

When I was first learning Elm, it was helpful for me to see side-by-side examples alongside ones from the JavaScript frameworks I was already familiar with.

In parallel I decided to learn a functional-first programming language instead of trying to partially apply the functional paradigm in an object-oriented language. After doing a lot of research, I chose to learn Elm. The fact that it is a pure and immutable functional language caught my attention. Also, it is focused on webapps development and, until then, I hadn't found any solution for developing web pages that I liked.

I'd like to report on a little weekend project, namely to implement an interpreter for a small subset of Scheme using Elm. Here is a screenshot of the command-line interface:

One alternative is the Model-View-Update framework developed in the Elm language [1]. A few years ago, it influenced Redux [2], but JS doesn't have good ergonomics to support it, so people complained it was too verbose. Anyway, I brought Elm to the company I worked at two jobs ago, and it worked very well, since it is conceptually very simple. The experienced developers loved its explicitness, which made it possible to build a very intricate app from just a few dependencies, which in turn allowed the company to have a very fine-grained control of the UI, and the customers loved the result.

On the other hand, other less experienced developers didn't like Elm so much because React allows you to write your app with fewer lines of code. The article from this discussion explains well that React (especially with hooks) hides complexity, which bites people later. At that time, it is perhaps too late to switch to something else.

Needless to say, I haven't been able to convince any other employer to use Elm, and then I see issues popping out all the time that would never happen with it. Such a waste, just because people like shiny toys and just follow what others around them are doing without thinking too much.

[1] https://elm-lang.org/