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by azangru 127 days ago
RxJS has an intrinsic diamond problem (multiple events fired when several sources update simultaneously), which led to occasional glitches. Signals are guaranteed not to have that problem. This is a strong argument in their favor.

But yeah; I am amazed and amused by how, during the past couple of years, the interest to rxjs has plummeted. No more conference talks on this topic. And even though Observables have been released natively, there is no activity in the rxjs repo to update the library accordingly.
1 comments
WorldMaker 127 days ago
As with most RxJS problems the diamond dependency problem can often be fixed/solved with the right combination of even more advanced operators/combinators. Often the easiest solution is `combineLatest`, but as mention that will over-fire depending on your update patterns. Sometimes a simple `throttle` is all the backpressure fix you need on that to reduce diamond over-firing, especially in combination with a cool scheduler such as `animationFrameScheduler` [0]. However there are also other domain-specific replacement options for `combineLatest` if you know the general event firing pattern such as `withLatestFrom`, `zip` [1], `join` [2], or `and/thenDo/when` [3] (in increasing complexity). (ETA: Not to mention that many diamond dependency problems are just fan out problems that can be solved by refactoring computations to an earlier point in the pipeline before the fan out rather than trying to fan back in.)

> And even though Observables have been released natively, there is no activity in the rxjs repo to update the library accordingly.

I believe this is still reversed: "native" Observables, the WICG Observables Proposal [4] is still marked as a Draft Group Report (not even officially a Proposal, still, ouch). The Issues of the RxJS repo still seem to indicate that everything is still in a holding pattern waiting for that to move.

I still cynically think this is yet another case of WICG holding the football in front of RxJS and just as likely as Lucy would do to Charlie Brown, will pull that football again right as they try to kick it, again. The WICG has acted like there is renewed interest in Native Observables but my cynicism thinks they are just rehearing drafts on it to appease the Observables crowd just long enough to claim more interest/easier implementation in Native Signals and try to get a Native Signals Proposal passed without good Observables interop. (But again, I'm a cynic here.)

[0] https://rxjs.dev/api/index/const/animationFrameScheduler

[1] https://reactivex.io/documentation/operators/zip.html

[2] https://reactivex.io/documentation/operators/join.html

[3] https://reactivex.io/documentation/operators/and-then-when.h...

[4] https://wicg.github.io/observable/

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