Closed
Description
TypeScript Version: master at bd40583
Search Terms: array index union error
Code
declare const arr1: (string | string[])[];
declare const arr2: number[];
const j = arr2[arr1[0]];
Expected behavior: Error - Type string[]
cannot be used as an index type
Actual behavior: No error
Playground Link: Link
Related Issues: Regressed during fix of #26409 (edit: #26281 ?)