Condition
A condition is an expression which should
result in a Boolean value. If it does not, a
debugging environment should flag it as an error and stop the program.
In programs that may not stop, any value other than True will mean
False.
Compilers used to compile programs which may not stop on errors are
expected to produce warnings for every condition which might not result
in a Boolean value.
Herman Venter
This is Slim documentation as snarfed on 27 May 1999 by dB.