Thanks. I'll work on this a bit. Pretty sure the above is possible, and maybe I can call the TypeScript API directly to compile/load from nbb. I'll research it.

How about coming at this from the other direction, and launching a REPL server from the JS end?

perhaps make an issue for this, I don't think this is currently exposed

Ah there an issue for it here: https://github.com/babashka/nbb/issues/132

@dave.dixon Publishing 1.1.145 now which should have this: https://github.com/babashka/nbb#nrepl-api

crap, build failure on CI

retrying a new publish

OK, this worked, version 1.1.146

Thanks. I seem to be stuck in module incompatbility hell, Instead change the require of /Users/dave.dixon/Projects/de_flare/node_modules/nbb/index.mjs to a dynamic import() which is available in all CommonJS modules., so far haven't been able to try this out. I'll see if I can find a workaround.

Yes, you could do this as a dynamic import in an async function if you’re using cjs

@dave.dixon Here is how you do that:

async function nREPL() {
  const { loadString } = await import('nbb');
  await loadString(`
  (require '[nbb.nrepl-server :as nrepl])
  (nrepl/start-server! {:port 1337})
`);
}

nREPL();

Thanks, but there's some issue with how we have our TypeScript project set up where it doesn't work. I either need to sneak in a pure JS script that avoids the TS transpiler, or get the right set of TS config options that won't break compilation on the rest of our codebase.

https://2ality.com/2021/06/typescript-esm-nodejs.html

Found a possible workaround here. The core problem seems to be that we use ts-node, and that has issues with ESM imports. But if I make our server startup pure JS, and tell ts-node to not transpile files with the .js extension, it works: ts-node --ignore \.js src/server.js. That also explains the error, which I think occurred because ts-node was "helpfully" converting import to require behind the scenes.

aha!