May 2018
Beginner
252 pages
6h 19m
English
Here is how if works:
;-- see Chapter04/conditions.red:account: -250if account < 0 [print "Your account is overdrawn."] ;== Your account is overdrawn.if now/time < 12:00 [print "before noon"] ;== before noon, if e.g. 10:53
The condition (here, account < 0 or now/time < 12:00) need not be enclosed in ( ), but the code following it must be in a block [].
Logical operations such as and, or, and not can be used to create composite conditions. For instance, here we use not to test whether a file is present, using the exists? function:
if not exists? %missing.txt [print "File missing.txt ...