TypeScript Without Transpilation (2021)

Post by Tade0 » Fri, Aug 11, 2023, 3:41 PM UTC

fenomas wrote: post #22

bandergirl wrote: post #9

Earlier quoted context omitted.

Not TypeScript the language, but TypeScript the typechecker program. “Typescript without transpilation” is still perfectly accurate.

Vouched. This is the point of the thing - the typechecking benefits come from running `tsc` on your code (or VSCode will do it for you in the background and show you linter errors if you have typescript installed somewhere it knows about). Incidentally I've been doing my JS projects this way for 2-3 years and I really dig it.

Post by fenomas » Fri, Aug 11, 2023, 4:12 PM UTC

Tade0 wrote: post #31

fenomas wrote: post #22

Earlier quoted context omitted.

Vouched. This is the point of the thing - the typechecking benefits come from running `tsc` on your code (or VSCode will do it for you in the background and show you linter errors if you have typescript installed somewhere it knows about). Incidentally I've been doing my JS projects this way for 2-3 years and I really dig it.

I started one side project like this recently and it's been great so far.

    var modeNames = { FOO: 1, BAR: 2 }

    /** @param {keyof modeNames} mode */
    export function doThing(mode) {
        // the jsdoc type above is equivalent to {'FOO'|'BAR'}
    }

Post by gsuuon » Fri, Aug 11, 2023, 4:48 PM UTC

jchanimal wrote: post #4

Does anyone know if I have a TypeScript project, is there an automated process to turn it into this format this article describes? Eject for TS, I guess.

Post by graftak » Fri, Aug 11, 2023, 5:07 PM UTC

stevebmark wrote: post #30

JSDoc comments are definitely not the “best of both worlds,” they are a limited and verbose subset of typing. I would only use them for specific reasons, like I’m in a hostile ecosystem that dogmatically doesn’t want any build steps (like WebGL/WebGPU engines).

Post by syspec » Fri, Aug 11, 2023, 5:17 PM UTC

afavour wrote: post #10

I've found a happy medium to be annotating functions etc with JSDoc style comments but keeping interfaces etc. in a .d.ts file. The Typescript compiler is able to import it from a .js file just fine.

  /// Top of file usually
  /**
   * @typedef {import('./typedefs/MyThing')} MyThing
   */
  
  /// Later
  
  /**
   * @param {MyThing} x
   */
  function(x) {
    //
  }