Using ocaml-lsp with Reason syntax

README.md

Configure VSCode with ocaml-lsp, esy and Reason syntax with ReScript/bs-platform.

It's a non-common setup

• If you want to target the browser and use ReScript syntax you can directly use https://github.com/rescript-lang/rescript-vscode and have similar support.
• If you do Reason these days (at the time I'm writting, arround September 2021) is commonly to target native development and you will use OCaml 4.12. In that case: follow the https://github.com/ocaml/ocaml-lsp installation.

but I find very useful, I keep liking more the Reason syntax and the ocaml-lsp experience it's much better than the rescript extension. Notably with the CodeLens support https://code.visualstudio.com/blogs/2017/02/12/code-lens-roundup with https://github.com/ocaml/ocaml-lsp.

So, If you want to keep using Reason syntax targeting the browser/node and have a good editor support, follow this:

Requirements

• https://esy.sh
• https://code.visualstudio.com

$ esy --version
0.6.11

Add dependencies (or devDependencies) in esy

$ cat esy.json

{
  "dependencies": {
    "@opam/ocaml-lsp-server": "1.4.1",
    "@opam/dune": "2.5.1",
    "@opam/ocamlfind-secondary": "1.8.1",
    "@opam/reason": "3.6.0",
    "ocaml": "4.6.x"
  }
}

# Install them
$ esy 

Install the VSCode extension

https://marketplace.visualstudio.com/items?itemName=ocamllabs.ocaml-platform

Enable esy as sandbox

CMD + P > "OCaml: Select a Sandbox for this Workspace" > Choose "Esy"

Hope it helps, if you find any issue please go to the Discord: https://discord.gg/T6YxT5JCWX