not

Type:	-	predicate function (subr)
Source:	-	xlbfun.c

Syntax

(not expr)

expr - the expression to check
return -  T  if the value is NIL , NIL otherwise

Description

The 'not' predicate function checks to see if the 'expr' is false.  T  is returned if the expression is NIL , NIL is returned otherwise.

Examples

(not '())      ; returns T - empty list
(not ())       ; returns T - still empty
(setq a NIL)   ; set up a variable
(not a)        ; returns T - value = empty list

(not "a")      ; returns NIL - not a list
(not 'a)       ; returns NIL - not a list

Note: The 'not' predicate is the same function as the null predicate.

See the not predicate function in the XLISP 2.0 manual.

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