let (signal, sink) = Signal<[CLBeacon], BeaconManagerError>.pipe()
When I call this because the user disabled the Bluetooth:
sendError(self.sink, error)
the Signal
is interrupted and I don't receive more next
nor interrupted
events after enabling the Bluetooth back again. The Signal
is broken.
How can I send error
types to the observer
without interrupting / breaking the Signal
? I can't find in the RAC 4 documentation. Thanks!
By design, an error causes the signal to finish. The documentation says:
failures should only be used to represent “abnormal” termination. If
it is important to let operators (or consumers) finish their work, a
Next event describing the result might be more appropriate.
If you want to turn errors into Next
events, you can use flatMapError
operator as described here or use retry
if you want to allow only several occurances of the error.
If you want different semantics than Next* (Error|Completed)
I recommend encoding that in the type. You can use a Signal
that can't fail, but which values can be either success or failure, by using Result
:
Signal<Result<[CLBeacon], BeaconManagerError>, NoError>
That signal
will emit no errors, but its Next
events will be Result.Success<[CLBeacon]>
or Result.Failure<BeaconManagerError>
, **and the signal won't terminate when receiving a Result.Failure
.