Is it possible to build a vscode extension from a javascript transpiler ? For example, is it possible to build an extension with "js of ocaml" or purescript. Those transpilers compiles to javascript. From what I understand, vscode extensions have to be built in typescript.
VS Code is essentially a browser (driven by the V8 Chrome engine) and hence can execute JS code directly (like any JS enabled browser). How you create the JS code is up to you. You can manually write it or transpile it from other code like TypeScript, PureScript and so on.