LISP Functions
(xunload)

(zerop)

(zerop number)

Determine whether this number is zero.

If number is a real number or an integer and it is a zero value, the zerop function returns a T. Otherwise, it returns a nil.

Examples

Code Returns
(zerop 0) T
(zerop 0.5) nil
(zerop 0.0000) T

Tell me about...

(atom item)

(boundp item)

(listp item)

(not item)

(null item)

(numberp item)

LISP Compatibility

Programming Overview of LISP (LISt Processing) Language