AppleScript: The Definitive Guide, 2nd Edition

Result

At runtime, a line of AppleScript code that actually executes an expression—that is, it isn't blank, a comment, or mere flow control (looping and branching)—will usually generate a result . This result is some sort of value; the particular value depends upon what the line does.

The line need not be a command; any valid AppleScript expression constitutes a valid line, even if it does nothing. For example, this is a valid line of AppleScript code, and it has a value (can you guess what it is?):

5

A line's result may be captured in two ways: explicitly or implicitly. The next two sections describe them both. As you'll see, my view is that in general you should not make any use of the fact that a line of code has a result. However, the exception proves the rule, so I will also suggest that in just one situation (while developing your code) capturing a line's value implicitly is useful.

Explicit Result

The result of a line after it is executed may be captured explicitly by using the keyword result in the next line that is executed. For example:

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display dialog result  5

One sees this technique used typically after fetching a value in a context of interapplication communication. For example, this is a fairly common style of coding:

tell application "Finder"
    get the name of every folder
end tell
set L to the result

Here's another example:

tell application "Finder"
    count folders
end tell
set c to the result

Why is this technique so common? It may be a habit derived from HyperTalk , where ...