TypeScript's [number] Index Signature: Extract Union Types from Arrays
Ever needed to create a union type from an array of objects in TypeScript? There's an elegant solution using the [number] index signature notation that can save you from maintaining duplicate type definitions. The Problem Let's say you have an array ...
Jul 19, 20253 min read42
![TypeScript's [number] Index Signature: Extract Union Types from Arrays](/_next/image?url=https%3A%2F%2Fcdn.hashnode.com%2Fres%2Fhashnode%2Fimage%2Fupload%2Fv1752960594694%2Fe2be9492-869f-4169-bb1a-950ee81a3887.png&w=3840&q=75)