[expr] [bool]ean negation operator

returns truth (1) if the argument is a falsehood, and falsity (0) of the argument is true

For bitwise "not" use the [~] operator.

[RS] 2008-12-04: To canonize a number into a boolean (0 for false, 1 for true) use !!.

----
!!!!!!
%| [Category Operator] |%
!!!!!!