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A comment on TypeScript types can run DOOM [video]. Parent comment

Re:TypeScript types can run DOOM [video] by matt_kantor on Wednesday February 26, 2025 @05:17PM (#43188889)
> it's just a set of all possible types

`unknown` is the set of all possible types (it's the top type[0]). `any` goes beyond that—it basically turns off the type checker[1][2].

[0]: https://en.wikipedia.org/wiki/Top_type

[1]: https://tsplay.dev/mA9vXm

[2]: https://www.typescriptlang.org/docs/handbook/2/everyday-type...

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Re:TypeScript types can run DOOM [video] by epolanski on Thursday February 27, 2025 @02:35AM (#43192178)
Your 1 isn't equivalent to my example, line 11 is not constraining the type.
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Re:TypeScript types can run DOOM [video] by matt_kantor on Thursday February 27, 2025 @07:05AM (#43193582)
I know it's not equivalent, it was just an example to show what `any` does (and that it's more than "just a set of all possible types").

The `T extends Record<any, any>` on line 11 is a type parameter constraint though. Are you referring to something else when you say "constraining the type"?

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Re:TypeScript types can run DOOM [video] by epolanski on Thursday February 27, 2025 @12:38PM (#43196564)
It works differently based on where those anys are and what that Record<any, any> refers to due to type variance.
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Re:TypeScript types can run DOOM [video] by undebuggable on Thursday February 27, 2025 @05:26AM (#43193024)
It's a "null" and "undefined" discussion all over, but now with transpiler.
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