Are there any plans for an online REPL for Rescript?

I think the playground is amazing, I love the new additions like types on hover! I was wondering if there are any plans in the works for a playground that executes the code, and not just shows the compiled output? Something along the lines of that renders the components would be awesome for sharing snippets or creating examples!



We’re (me and my friends from the ReScript Brazil community) planning to develop a very similar project. We call it “ReScript Learning Lab”. It will be more than a simple tutorial, we want to help the newcomers to learn the language from the beginning to the intermediate. Probably we’ll develop a REPL / Playground that not just shows the output, but executes and renders the components.

If there are any plans for the official playground to implement a feature that executes the code and show a preview, we would be happy to help :slight_smile:


Yeah, we want to eval the code at some point (that’s what you mean by REPL I believe?).

The current playground handles multiple versions of the playground bundle, which means you have different versions of runtime libraries (stdlib, rescript-react). Unload / reload JS files is a little tricky; it’s important to make sure you are not mixing runtimes (playground / cmijs).

So if you figure out a way to load the playground bundle / runtime libs (wüespecially in a web worker), we can integrate it in the playground.

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Just remembered that I talked about the problems in one of my stream recordings:

I would be interested to see codepen enhanced for this use case as well.

Maybe it’d be valuable to get a first-class template on — they’ve had first-class reason lol support for some time.

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I went ahead and got a functional codesandbox template working:

Obviously the big issue is no syntax support.


I realise this thread is a year old, but I found out recently that its easy to use to run rescript online in an online vscode with the rescript extension installed.

I created a repo here with the required .gitpod.yml file:

To run, all you need to do is click on: and it will ask you to login with github and then you will have vscode with rescript running in the browser.

I’m not affiliated with them btw, i just thought this was cool.