SimEvent type has three constructors, SimEvent, SimPOREvent and SimRacesFound. SimRacesFound is only internal, and one shouldn't need to pattern-match on it when using io-sim. SimEvent should be redesigned so the compiler does not require pattern matching on SimRacesFound.
SimEventtype has three constructors,SimEvent,SimPOREventandSimRacesFound.SimRacesFoundis only internal, and one shouldn't need to pattern-match on it when usingio-sim.SimEventshould be redesigned so the compiler does not require pattern matching onSimRacesFound.