Run the first Automaton until the second value in the output
tuple is Just c, then start the second automaton, discarding
the current output b.
This is analogous to Yampa's switch, with Maybe
instead of Event.
Run the first Automaton until the second value in the output
tuple is Just c, then start the second automaton one step
later (after the current b has been output).
Analog to Yampa's dswitch, with Maybe instead
of Event.