aberdeen VS Elm

We've had great results from our custom built non-pure reactive system (which predates React by a couple of years).

The idea is to have an Observable object that can store arbitrary trees of data (each itself an Observable). UI drawing is generally split into a function call for each DOM element that has children. These functions are executed such that they track the use of observables and will be rerun when they change.

I've more recently, after having suffered React and friends, started creating an Open Source implementation of the pattern we used. Currently, it's mostly still lacking in documentation and marketing, and that's unlikely to change if I'm honest. But this should give you an impression if you're interested:

https://github.com/vanviegen/aberdeen/blob/master/examples/t...

Curious to know your thoughts about this being an effective non-pure reactive system.

Yes, that's possible and works really well.

I've written this library [1] as a clean reimplementation of a more complex beast we created for a (now dead) startup. Although the reimplementation has only seen very light use, we've used the concept extensively, and it's a joy to use. Take a look at the examples [2].

[1] https://github.com/vanviegen/aberdeen

Elm [1] is based on a similar idea. Build your app from pure functions that return HTML tags.

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

You also wouldn't really be creating your own new programing language. You would be creating something that can run JavaScript by following JavaScript standards and syntax. You might be able to add some non-standard features of your own on top of those standards, or include your own standard library of helpers or utilities, but you can't completely make a new or alternative language and then load it in the browser (or at least not by reimplementing ECMAScript standards... you actually can make your own language that runs within any Javascript enviroment, if you provide an interpreter or compiler that transforms it into valid JS. Some people have done something like this, eg Elm: https://elm-lang.org/).

You should at least have a look at https://elm-lang.org/ it is a pure functional language like Haskell (although with fewer fancy syntax/type classes) but it has some lovely libraries for visualisation and even with plain elm (+ elm-ui) doing string transformations can be easily done.

I get it. However, the whole point of using Unions to narrow your types, ensure only a set of possible scenarios can occur, and only access data of a particular union when it’s safe to do so. That’s some of what pattern matching can provide, and 100% of what using switch statements in TypeScript with their Discriminated Unions can provide. Yes, it’s not 100% exhaustive, but TypeScript is not soundly typed, and even Elm which is still has the same issue TypeScript does: You’re running in JavaScript where anything is possible. So it’s good enough to build with and much better than what you had.

The beauty of a language like Elm (and other lambda-calculus / functional programming inspired languages) is that there's very little transformation involved in going from an idea to code. And that seems to have a big impact on getting things done.

I think the most fun and approachable way for beginners to build games with functional programming is with Elm [1].

See a few (small, demo) games built by the community in [2] .

Notice Elm has abandoned the FRP approach in favor of Model-View-Update [3].

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