Creating an array with varying types for the first element and remaining elements

Trying to properly define an array structure like this:

type HeadItem = { type: "Head" }
type RestItem = { type: "Rest" }

const myArray = [{ type: "Head" }, { type: "Rest" }, { type: "Rest" }]

The number of rest elements can vary, but the first element always must be a head element. One way to define the array is shown below, however, the ...rest ends up with an incorrect type of (HeadItem | RestItem)[].

type MyArr = [HeadItem] & RestItem[];
const [head, ...rest] = myArray as MyArr;

What would be the correct type for MyArr so that the ...rest is correctly deduced as just RestItem[]?

typescripttypes

Answer №1

You can try this method:

let array: [firstElement, ...restElements[]] = Arr

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