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iOS Build a Blog Reader iPhone App Data Modeling Designated Initializers and Convenience Constructors

Posted by Pallavi Polisetty
Pallavi Polisetty
Courses Plus Student 1,423 Points

Hi there, could anyone of you please clarify the difference between nil, Nil, NULL, NSNull and when to use that

please clarify when to use nil, Nil, NULL and NSNull and what's the difference between that

1 Answer

Thomas Nilsen
Thomas Nilsen
14,957 Points
Thomas Nilsen
Thomas Nilsen
14,957 Points

Here is a nice answer I found from a post on SO (Stack Overflow).

All three of these values represent null, or zero pointer, values. The difference is that while NULL represents zero for any pointer, nil is specific to objects (e.g., id) and Nil is specific to class pointers. It should be considered a best practice of sorts to use the right null object in the right circumstance for documentation purposes, even though there is nothing stopping someone from mixing and matching as they go along.