Verifies that an item is bound to nil
Supported Platforms: Windows and Mac OS
(null item)
Type: Integer, Real, String, List, Ename (entity name), T, or nil
An AutoLISP expression.
Type: T or nil
T if item evaluates to nil; otherwise nil.
(setq a 123 b "string" c nil) nil (null a) nil (null b) nil (null c) T (null '()) T