t3x.org / sketchy / library / not.html
SketchyLISP
Reference
  Copyright (C) 2006
Nils M Holm

not

Conformance: R5RS

Purpose: Logical negation (NOT).

Arguments:
A - truth value

Implementation:

(define (not a)
  (eq? a #f))

Example:

(not #f) 
=> #t

See also:
neq?.