Safari Books Online is a digital library providing on-demand subscription access to thousands of learning resources.
If you've programmed before, you may have noticed that when you define your handler in AppleScript, you don't declare the types of the arguments it takes. Nor does AppleScript do any checking on the types of arguments you supply when you call the handler. AppleScript just makes sure that you supply the correct number of arguments to the handler. That means if you write this call
sum(100)