In BSShuffler isValidShuffle... add comment Swift switch cases do not "fall through". Delete default: to eliminate Xcode warning that it will never be executed.
In BSShuffler isValidShuffle... add comment Swift switch cases do not "fall through". Delete default: to eliminate Xcode warning that it will never be executed.

https://developer.apple.com/library/ios/documentation/Swift/Conceptual/Swift_Programming_Language/ControlFlow.html

beepscore/ShuffleSwift