Convert gluegun source to TypeScript

I’m about 80% through a major refactor, which includes converting over to TypeScript. So I’m filing this issue to track some of the items.

1. I’m using ts-node right now, and it works pretty well. However, my assumption is that we should keep this as a devDependency and compile a JS bundle … when other CLIs import gluegun, they get the JS bundle. Is that right, or can we assume ts-node as a full dependency and call it good?
2. If we do compile a JS bundle, we lose some of the debugging capability in the wild, because we won’t get reasonable line numbers.
3. If we do compile, we could conceivably target/support older versions of node. Should we?

[skellock]

1. Yes, you are right.

ts-node is great for dev but not for shipping. TypeScript isn’t really a bundler so it won’t pack up dependencies. It just turns our source into a different source. There will be a build step required for shipping. Add outDir: dist to the tsconfig.json (for example) then run tsc -p . and we’re done.

1. Source maps is how you fix this.

sourceMaps: true in our config will emit these. With the right target setting, the output of ts is remarkably human. Not like Babel. In practice this isn’t a big deal. Being a superset of js is an advantage here. 🥇

1. Yes and yes! Allowing people to opt-in to dependencies is the right way (albeit a little more work).

I also recommend going the bundle route on top of all this. Multi-format would be great to give more flexibility to our downstream. rollup can do all of this. And providing instructions to clis on how to do this too would be way above & beyond. 🏆

[GantMan]

Supporting older versions of NODE!? Woah! epic!