Exception handling

Handling exceptions in reactive programming with Rx is something odd. We're used to handling exceptions by writing code that executes when some other code hangs. More precisely, we write multiple execution flows that execute when the application runs properly or badly. The real meaning of exception handling means handling an exception in the usual way of doing something. Exception handling is not error handling.

Although, this being a philosophical definition, we're used to using exception handling to handle unpredictable behaviors.

In Rx, exception handling is identical with the difference that here we don't deal with code rows that execute one by one; we actually deal with the sequences of messages that must continue flowing regardless of whether an exception may invalidate one or multiple messages. In smarter words, the show must go on. Obviously, a single exception must prevent the whole sequence from running anymore.

In other (simpler) words, when we want to handle an...