public static void OneToOneRelationTest(bool useTuples) { var arr = Array.Empty <(int, double)>(); var r = useTuples ? Relations.AsBijective(arr) : Relations.AsBijective(arr.Select(t => KeyValuePair.Create(t.Item1, t.Item2))); Assert.Empty(r.Elements); Assert.False(r.MaybeResult(3).HasValue); Assert.False(r.Contains(1, 3D)); Assert.False(r.Contains(2, 2D)); Assert.False(r.GetMaybeLeft(3D).HasValue); Assert.False(r.GetMaybeRight(3).HasValue); arr = new[] { (1, 2D) };