TutorialState PreviousTutorialState(TutorialState state) => Enum.GetValues(state.GetType())
.Cast <TutorialState>()
.Concat(new[] { default(TutorialState) })
.Reverse().SkipWhile(e => !state.Equals(e))
.Skip(1).First();
TutorialState PreviousTutorialState(TutorialState state) => Enum.GetValues(state.GetType())
.Cast <TutorialState>()
.Concat(new[] { default(TutorialState) })
.Reverse().SkipWhile(e => !state.Equals(e))
.Skip(1).First();