Typescript how to define array type with nested and predict

Question

How to set the type for an array like

["string", [”string", ["other string"],["any"]], [”string", ["string”, ["something string"]]], ....]

That is, the depth can be any. Number of arrays after index '0' is also. The main condition, the type under the index '0' must be 'string'.

coravacav · Accepted Answer · 2021-01-28 23:06:42Z

1

This works:

type ValueOrArray<T> = T | ValueOrArray<T>[];
type NestedStringArray = ValueOrArray<string>;

Or, more directly for your answer:

type StringOrArray = string | StringOrArray[];
type NestedArray = StringOrArray;

Then just type your array with NestedStringArray

answered Jan 28, 2021 at 23:06

coravacav

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1 Comment

I found almost the same thing on your link.type NestedArray = string | [ string, ...NestedArray[] ]; its work.thanks