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Comment by chfritz | Hacker News Reader

Doesn't your counter-argument beg the question whether it is indeed 20% BS vs. 80% value? I think the OP is asking about pretty much that percentage. Personally I feel it's more like 70% BS vs. 30% value. Types, after all, are a very weak ontology, i.e., you still cannot know for sure that just because your code compiles it interprets the values it's getting from other party's code correctly. I would even argue that it may create a false sense of safety -- just think of the Mars satellite that crashed because some developer thought a number was in imperial units when, of course, it was in SI.

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You need to parse and/or validate any external input before you declare that a variable or field is a certain type, as you probably should be doing without Typescript anyway. Being strict in what you accept and ensuring that you're not lying to the type checker solves the vast majority of these types of issues.

It's been a few years since I worked with TS professionally, but at least at the time, I saw it as 95% value, 5% BS. It provides such plainly obvious value in my eyes that I've decided I'll never write JS again unless it's a single file script or a small throwaway project/PoC.

In my experience, even the one file scripts eventually get converted to Typescript when I realize I cannot specify my types :)

Come on, the OP literally said:

> I want to skip over the static typing benefits argument, because I think it is well understood that static typing is a good thing

The OP is interesting in talking about how much of a pain in the ass TS tooling is, and... it's fair to say it's annoying.

If you accept that static types are good (and the OP explicitly said they do), then what are going to do? Basically the OP is saying, "I want static types but not the TSC compiler or ecosystem"; well... it sucks, but you're never going to get that.

The comment you're replying to is just saying: "Well, if you want static types, you gotta live with the bad stuff".

> Doesn't your counter-argument beg the question whether it is indeed 20% BS vs. 80% value?

Nope.

Let me clarify - I pretty much agree with what the parent says - "it's more like 70% BS vs. 30% value".

I do still want that value i.e. static typing, but as you point out I can't get that without the BS. And so I would rather have no typing which is the only other option (except using a different language).

> And so I would rather have no typing which is the only other option (except using a different language).

This part is what is so wild to me. I simply cannot imagine throwing the baby out with the bathwater, so to speak, to throw out the entirety of static typing just because of the BS around it. In my experience, static typing is superlative, it would have to be some extremely rare situation for me to give it up.

I spent 6 years programming production JS delivered to millions of people before I went to TS and it just wasn't that bad. The code was clean, and the team didn't ship many bugs - this was for a big frontend and ~12 microservices.

Webpack added a lot of overhead - but if you know what came before it, it was a godsend. React added a super complex library, vs Backbone which was only a few hundred lines of code but React is totally worth it.

I'm not just trying to hark back to "the good old days", I think the ecosystem is a big improvement from where it came from but I just haven't seen enough benefit from TS for all the work you need to put in.

We have that in the form of ReScript.

Types help prevent a narrow class of errors. They also help with refactoring. They help avoid messy checks getting in the middle of your business logic. All of this is more than enough to justify using them.

Types do not replace other checks and tests.

I don't think the Mars satellite crashed because they trusted the type system.

> Types, after all, are a very weak ontology, i.e., you still cannot know for sure that just because your code compiles it interprets the values it's getting from other party's code correctly.

This again seems to be throwing the baby out with the bath water. Just because in some cases types can't be verified does not mean we should fully be without types at all. There are a myriad of ways to mitigate even this, Parse, Don't Validate comes to mind [0]. Type Driven Development is another way [1], as well as using runtime type checkers like Zod. This article by Kent C Dodds is a really good example of the latter, it covers everything you're talking about regarding unknown types [2].

> I would even argue that it may create a false sense of safety -- just think of the Mars satellite that crashed because some developer thought a number was in imperial units when, of course, it was in SI.

Actually, that sounds to me like just the opposite case. The dev thought it was in imperial units because they might not have known the type of said number. If the number was instead typed with `ImperialUnit unit = ...`, that issue might not have occurred. Now, if the unit value was inputted incorrectly by the programmer, that's a different issue, no amount of typing will fix a business logic typo. As well, if the satellite was fully untyped, issues like these would have occurred far more often, so taking a singular example as a damnation of an entire paradigm doesn't really work.

[0] https://news.ycombinator.com/item?id=27639890

[1] https://blog.ploeh.dk/2015/08/10/type-driven-development/

[2] https://www.epicweb.dev/fully-typed-web-apps

I like TS for the completions and the documentation. I know OP was complaining lack of documentation but knowing what properties a giant object takes, even if those props don't have doc-comments, is still wonderful.

What I've been doing is, whenever I'm handed a random JSON blob, I throw it into a JSON->TS interface converter, paste that back into my project, and I never have to question what the heck the server is returning to me again.

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