An immutable type that may contain a value or reference. Each instance of this type either contains a non-null value or reference, or contains nothing (in which case we say that the reference is "absent"; it is never said to "contain null").
2 years ago
4 Answers
3 Answers
3 years ago
2 Answers
39 Questions - 0 Points
42 Questions - 0 Points
43 Questions - 0 Points
41 Questions - 0 Points
45 Questions - 0 Points