AppleScript: The Definitive Guide, 2nd Edition

Is This Application Scriptable?

AppleScript isn't just a language; it's an underlying technology supporting that language. Because this technology is present as part of the system, you get it for free—so you may as well take advantage of it. And because you know this technology will be present on any Mac OS computer, you can share with others any useful AppleScript program you happen to write.

So AppleScript is omnipresent. But it's not omnipotent. AppleScript, remember, is all about telling an application to do automatically things of the sort you might make it do manually. But AppleScript does not let you tell every application to do everything it is capable of. AppleScript works by sending messages to the applications you are automating; these messages are called Apple events. You cannot send just any old Apple event to any old application. (Well, you can, but it might not have any effect.) The application to which you're sending an Apple event must recognize and respond to that Apple event. The ability to recognize and respond to a set of Apple events is a feature of the application. Giving the application this ability is up to the developers of the application—it isn't something that's within your power (unless you are also the developer of the application). An application that has this ability is said to be scriptable . If an application isn't scriptable, you're probably not going to be able to use AppleScript to automate it. (As you'll see in Chapter 24, there is sometimes ...