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A comment on TypeScript vs. ReasonML. Parent comment

Re:TypeScript vs. ReasonML by hajile on Wednesday September 04, 2019 @05:58PM (#20881830)
If you turn off `any` on a gradually-typed codebase, everything will blow up because of the untyped parts. Gradual typing CANNOT be sound unless you dynamically typecheck everything (at which point you are just doing what JS devs do anyway).
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Re:TypeScript vs. ReasonML by eatonphil on Wednesday September 04, 2019 @06:11PM (#20881921)
> If you turn off `any` on a gradually-typed codebase, everything will blow up because of the untyped parts.

Again, that's not true. A JavaScript file's exports don't have `any` type. Any types during interop are inferred (maybe?) or require bindings. The use of `any` in bindings is your (sometimes valid) choice.

> Gradual typing CANNOT be sound

TypeScript isn't sound [0].

[0] https://github.com/Microsoft/TypeScript/issues/9825

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