On: TypeScript 5.2's new keyword: 'Using'

[recursive]

How? WeakMap (and WeakSet, more directly) can detect if an object has been collected only if you have a reference to pass to it. If you have reference to the object in a variable or data structure, it won't have been eligible for collection in the first place.

[bakkoting → recursive]

You can't use a WeakMap or a WeakSet, but you can use a WeakRef or a FinalizationRegistry.

[recursive → bakkoting]

I did not know about these things. Looks cool!