uncaughtExceptionPreHandler does not exist

[NWuensche]

I tried to implement a global coroutine exception handler. However, the uncaughtExceptionPreHandler from the wiki does not exist. I also added the kotlinx-coroutines-android lib in version 1.6, but I still don't get this. Is the wiki outdated, as the readme also does not say anything about uncaughtExceptionPreHandler nor Thread.uncaughtExceptionPreHandler?

[dkhalanskyjb]

The docs should be updated, as the implementation changed since then.

In any case, you shouldn't have to do anything, the docs only describe what our library does on its own. Adding kotlinx-coroutines-android as a dependency should be sufficient for uncaught exceptions in coroutines to be propagated to the Android runtime, one way or another.

[NWuensche]

Thank you for the reply. However, I would expect that I can somehow install my own global CoroutineExceptionHandler, where I can say "write to this log" or something like that. Something like `RxJavaPlugins.setErrorHandler` in RxJava. Is there no option for that?

[qwwdfsad]

We do not have option for that and we do not intend to provide one. Reactive frameworks experience showed us that having a global mutable state for dispatchers, error handlers, various on* hooks and shutdown hook is the very common source of non-deterministic bugs as the behaviour depends only on who is invoked first/last and has its Rx*Plugins.set* won.

The suggested solution is to have your own CEH in application-specific top-level scope.

[NWuensche]

Thank you. However, maybe you shouldn't write "...it is possible to redefine global exception handler for all coroutines" in the documentation then, but maybe write that this is indeed not possible/recomended :) . I would also like it if you could give an example in the documentation on how to define a CEH on top-level scope. I work on Android, and I'm not 100% how to do this considering using the provided lifecycleScope and viewModelScope. It would be really annoying to add (and maybe forget) a CEH to each scope separately.