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> Show me a Typescript codebase not using the type 'any'!

Show me a Java project without an unchecked cast... I’m not a CS person but my impression is that sometimes you need these types and they exist in the type system for a reason. No type system is conceptually “perfect” as in there are soundness/expressively tradeoffs. I don’t think using ‘any’ is always bad. Sometimes it’s even right?

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There are type systems that don't have anything like "any" - you find that in languages like OCaml or Haskell.

But in TS, the main reason for "any" is interop with JS.

Thanks. So in OCaml/Haskell you can write perfectly sound programs?

Well, I mean, you can write perfectly sound programs in Java as well, or in TS. It's rather a question of how hard/easy it is to do so. Technically, any language that has either direct memory manipulation or FFI has the potential to do unsound things about types, but it takes a lot more effort.

Haskell's type system still isn't sound. It just elimates that particular class of errors.

A lack of soundness is closely related to the Turing completeness, especially in languages based on HM. In an ideal world you would want a sound type system and not want Turing completeness, but the tooling doesn't exist to make those choices the most pragmatic right now.

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