Hello, I've got Swift 5.0 running on Linux (Raspberry Pi) - Thanks @futurejones and @uraimo ! And also Swift 5.0 via Xcode 10.2 on macOS.
There seems to be a disparity in the types of RunLoop Modes. To keep both versions of the compiler happy I must do this:
func run() {
#if os(macOS)
while shouldKeepRunning == true &&
runLoop.run(mode:RunLoopMode.defaultRunLoopMode, before: distantFuture) {}
#endif
#if os(Linux)
while shouldKeepRunning == true &&
runLoop.run(mode:.default, before: distantFuture) {}
#endif
}