The special value, nil, is a zero-length list. It is the only logically false value in Gamma. All other Gamma values are considered to be logically true. A common mistake for first-time Gamma programmers is to treat the number zero as logically false.
Gamma> x = 5; 5 Gamma> x > 10; nil Gamma> int_p(x); t Gamma> real_p(x); nil Gamma> !3; nil Gamma> !t; nil Gamma>
Copyright © 1995-2006 by Cogent Real-Time Systems, Inc. All rights reserved.