A guide to utilizing the spread operator within a typescript tuple

Is it possible to set the structure of an array without knowing the exact number of elements it will contain? How can I achieve this flexibility in defining array configurations? (Check out a playground version here):

type numStrArr = [number, ...string];

let arr: numStrArr = [1, 'hi', 'other string'];

An error is thrown with the message Type expected. at the spread operator in the code above.

Although there was a proposal addressing this issue, what are the current methods to achieve similar behavior?

typescripttypestuplesspread-syntax

Answer №1

Although this query is from 3 years ago, the functionality has been updated and now works. Just adjust the data type to one that can be distributed across. For more information, check out this resource:


// Error-free zone...
type mixedArr = [number, ...string[]];

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