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0 pointsMrJohz3y ago0 comments

> I think maybe the underlying problem here is that some people somehow manage to write javascript inside .ts files[...]

I don't think that's it. I write pretty much exclusively typed code, except in places where I've not managed to get everything set up properly (mainly old Vue2 code). And even then, imports are unidirectional: JS can import TS, but TS can only import other TS files.

As to the "world of uncertainty", this lasts surely less than 100ms for me, certainly little enough time that it feels instantaneous. Usually I get feedback as I'm typing, sometimes if I'm doing things in new files I need to save the file first, but either way, my IDE is consistently fast enough that I know immediately if my code type checks or not. There is no downtime here at all.

As for seeing the code change, I usually have the page open on a second monitor, so I press "save", and glance over to my second monitor, and with live reload and a good configuration (that's harder to achieve on some projects, I grant you), I'm usually already looking at the results of my changes.

In practice, I very rarely have any uncertainty about what typescript thinks my types are - this information is always immediately at my fingertips. Where I do have uncertainty sometimes is whether the javascript types match the expected typescript ones - this often happens when I'm dealing with third-party libraries, particularly when `any` types start popping up. In that case, it's occasionally useful to ignore the type checker altogether, play around with some different cases, and then come back to ensuring that the types match later. That's just not really possible if you're treating the type checker and the compiler as an all-in-one unit.

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Nathanba3y ago· 1 in thread

>with live reload and a good configuration (that's harder to achieve on some projects, I grant you),

right but livereload has the same problem as you: The build is already done so it reloads but lets say the typecheck will error out because surely you save a file more often than you want to recompile. So your page just reloaded which you didn't intend, in fact, it might actively have destroyed a debugging session which you didnt want to reload yet. How do you configure that away to make it work sensibly? And here is the kicker: I know you can configure your livereload build so it only reloads after the build and the typecheck are done. But this is precisely how we ended up discussing this.. now you always depend on both the typecheck and the build to end before you can test your change anyway.

MrJohzOP3y ago

I don't think I really understand your objection. Live reload, at least as I've got it set up, doesn't really work that way: it won't interrupt an in-progress debugging session, and the application state is retained (at least if one sets everything up correctly). Besides, type checking in my editor doesn't normally require me to save the file, so I usually know whether the code is valid or not before the build starts. So I don't have the problem you describe in the first place. Moreover, as I pointed out, I find it useful to be able to occasionally run code that doesn't type check, so there's a very real downside to waiting for the type checker to finish before building.

I suspect we're just used to building code in very different ways. If you've not tried approaching typescript as a linter rather than "just" a compiler, I really recommend giving it a proper go - it feels very freeing, and I think is one of the biggest advantages of typescript as a tool/concept. (It obviously has its own disadvantages compared to how, say, a traditional AOT compiler would work, namely that tsc can never really take advantage of types at all during the compilation, but it gives you a lot of flexibility during development - essentially the best of both worlds for dynamic and static type systems.)

That said, if you've already tried it and know it's not for you, then fair enough - ultimately all of these tools are just ways for us to write code, so if you write code best in this way, then I don't want to try and force you to do it some other way!