flat Map Maybe
Calls the mapper for each element emitted by the Observable and subscribes to the returned inner Maybe. Emits elements from inner Maybes. The maximum number of concurrently subscribed inner Maybes is determined by the maxConcurrency argument.
By default, all inner Maybes are subscribed concurrently without any limits.
Please refer to the corresponding RxJava document.
Calls the mapper for each element emitted by the Observable and subscribes to the returned inner Maybe. For an element U emitted by an inner Maybe, calls resultSelector with the original source element T and the inner element U, and emits the result element R. The maximum number of concurrently subscribed inner Maybes is determined by the maxConcurrency argument.
By default, all inner Maybes are subscribed concurrently without any limits.
Please refer to the corresponding RxJava document.