WeakMap entries with tuple keys might get lost after GC

[0f-0b]

Run the code below with node --expose-gc. One might expect the output to be value, but it actually prints undefined.

import { Tuple } from "libtuple";
import { setTimeout } from "node:timers/promises";

const data = new WeakMap();
data.set(Tuple("key"), "value");
await setTimeout();
gc();
console.log(data.get(Tuple("key")));

I think this should be documented under the “Limitations” section of the readme, because I don't see a way to fix this without causing memory leaks.

[seanmorris]

hmmm, I'll need to really think about this one.

[seanmorris]

I wonder if a comparison to registered symbols would be helpful in deciding on the correct behavior would be helpful here.

If I recall correctly, registered symbols can't participate in WeakMaps or WeakSets, but I wonder how the memory is handled under the hood for those.

If you call Symbol.for('foo'), and then the resulting value is gc'ed, and then you call Symbol.for('foo') again, do you get back the "same" value, or is it just the "same" for "all" intents and purposes?