Over lunch I was discussing ES6 and ES7 features with some developers doing JavaScript crypto, and they mentioned an interest in not only weak references, but weak callbacks. That is, a notification when your object gets garbage collected, similar (I think) to what V8 has with its `MakeWeak`, and what C# has with its finalizers.
Such a feature would be non-deterministic, since it depends on when the garbage collector runs; the callback may never run at all. But it could be useful for performing cleanup tasks related to a given weak reference. I imagine it could even be emulated with polling plus weak references, so there should be nothing fundamentally new here. Personally I would find this feature somewhere between useful and an attractive nuisance. It would have to be carefully advertised as for last-ditch cleanup, not a substitute for deterministic disposal (via e.g. a `dispose()` method). C# has a similar dichotomy, with `IDisposable` for deterministic disposal, and a conventional pattern where you call `dispose()` in your finalizer if the consumer forgot to do so themselves. What do people think of this feature? _______________________________________________ es-discuss mailing list es-discuss@mozilla.org https://mail.mozilla.org/listinfo/es-discuss
