Duplicate types are allowed (and ignored) if the first type is exported #36196

TypeScript Version: 3.7.2

Search Terms: duplicate type identifier export ignored allowed

Code

export type A = 1;
type A = 2;
const x1: A = 1;

Expected behavior: I think this should not be allowed: I'm defining a duplicate type, the first of which is exported. Still, it's a duplicate.

Actual behavior: This is actually allowed, and the second definition is completely ignored. (Note that any other arrangement of export keywords cannot make the program correct, only this works.)

Playground Link: http://www.typescriptlang.org/play/#code/KYDwDg9gTgLgBDAnmYcCCcC8cCMBuAKCRXSzgCZCBjCAOwGd4QcAuU7fAoA

Related Issues: I did not find any.

(Sorry if this is a duplicate. It feels too simple to not be one, but I didn't find it.)