UdpClient (Reactive) does not work with Merge (Observable)

The same behavior on Preview and Stable:
Freezes, lags, pop-up tips on nodes disappear and at the end the connection does not work
This behavior, as I understand it, occurs only after merge node

merge_obesrvable_udpclient.vl (19.1 KB)

Its a small small things, but try

  • putting the create and ToObservable nodes inside a cache,

  • and connect the IPEndpoint directly to the create and Port nodes.

Does that improve anything?

@Hadasi There are fewer lags. But the popups did not appear. UDP still doesn’t work

merge_obesrvable_udpclient3.vl (21.8 KB)


two things:

  • instead of Merge [Observable] use Merge [Reactive]
  • on my machine port 4500 is used by another process. so make sure the port you’re using is free. e.g. on a commandline type: netstat -anop udp

and no need to put the ToObservable nodes in a cache region, they only operate when you enable the Send input.

@joreg thank you


The port is also busy, but it was “merge (reactive)” that helped

Ninja-ed - Merging Observables.vl (23.2 KB)

I also found that the port was the main issue.

@Hadasi Did you try with latest gamma?


Yep. Check with .4.10 .4.11 and .5.0
Give my patch a try

Nice! Now I get it. Thank you, it really works.

Is it a construction that provides stable functionality?
Weird one, Merge (Reactive) works perfect btw


Any time! The toggle was just for me to check that the merge was setup okay, you can ignore it.

The merge in the cache means that it creates just one pipeline so to speak, that’s also what the changed node connected to the Toobservable demonstrates: once the pipeline is setup, the data triggers the action internally but on the outside nothing changes.

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@Hadasi anyway, merge in this case really doesn’t work without the cache region, but cause some not obvious and serious bugs. It’s amazing that we figured out how it works. Although some error is present.