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A comment on TypeScript 5.0. Parent comment

Re:TypeScript 5.0 by triyambakam on Friday March 17, 2023 @01:59PM (#35200531)
Or better:

    type NonEmptyArray = [unknown, ...unknown[]];
    const nea: NonEmptyArray = [];
    //    ^^^ Type '[]' is not assignable to type 'NonEmptyArray'.
    //        Source has 0 element(s) but target requires 1.
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Re:TypeScript 5.0 by throwaway09432 on Saturday March 18, 2023 @01:30AM (#35206420)
Can you map over this and preserve the NonEmptyArray type?
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Re:TypeScript 5.0 by triyambakam on Sunday March 19, 2023 @03:00AM (#35216711)
Do you mean pass in a type?

    type NonEmptyArray<T> = [T, ...T[]];
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Re:TypeScript 5.0 by throwaway09432 on Sunday March 19, 2023 @09:00AM (#35218504)
I mean if I have a NonEmptyArray say xs, and I then xs.map(x=>2*x), will the result of this expression be a NonEmptyArray ?
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Re:TypeScript 5.0 by triyambakam on Tuesday March 21, 2023 @08:28PM (#35254947)
No, unfortunately it will just be number[] as the return type.
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