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Discussion on: Thoughts on migrating to TypeScript and improving the overall quality of the frontend DEV codebase

john_papa profile image
John Papa • Edited

Thanks for replying! These are good questions to ask. They are not "stupid" in my opinion :)

You do write more code with TS, but you also get a stronger sense of finding issues while coding vs finding them while they code is in production. To me, one of the biggest values in TS is that many potential bugs surface themselves at dev time vs run time.

Is there value in only having new code in TS? There can be as this new code would make me feel more confident. You can also add the // @ts-check to existing JavaScript in VS Code ... give that a shot. That alone is quite amazing at what it can surface in existing JavaScript.

New thought --- Another option is to run the typescript compiler on javascript. No TypeScript at all. The compiler will examine the javascript and report any issues it finds (it's like adding ts-check to all of your files). I did this on a large codebase and it did indeed surface a lot of potential issues that were hiding. This is a super low (no) risk way of trying it.

Again, thanks for the great questions. Always good to ask - especially if something isn't quite feeling right.

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karataev profile image
Eugene Karataev

Oh, I didn't know that I can run typescript compiler on javascript code without modifying the existing code. Thanks, I'll give it a try.

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john_papa profile image
John Papa

Set allowJs to true in the tsconfig.json file to tell typescript to look at the js.

Good luck!

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amcsi profile image
Attila Szeremi⚡

Why didn't you just recommend this from the start? Seems a lot simpler than to add // @ts-check to every single JS file like you said in your original comment :P