AppleScript: The Definitive Guide

Calculation and Repetition

Computers are good at calculation and repetition—which happen to be exactly the things humans are not good at. Humans are liable to calculate inaccurately, and repetitive activity can make them careless and bored. The whole idea of having a computer is to have it take over in these situations.

Here’s an example. Someone on the Internet writes: “I want to rename a whole lot of image files based on the names of the folders they’re in.” One can just picture this user’s eyes glazing over at the thought of doing this by hand. This is just the sort of thing a computer is for.

The task would make a good droplet. A droplet is a kind of applet, which is a little application you write with AppleScript, such that you can drop the icons of files and folders onto the droplet’s icon in order to process those files and folders in some way. (See Section 4.6 and Section 24.1.) So here’s the AppleScript code for a droplet where you drop a folder onto its icon and it renames all the files in that folder as the name of the folder followed by a number:

on open folderList repeat with aFolder in folderList tell application "Finder" if kind of aFolder is "Folder" then my renameStuffIn(aFolder) end if end tell end repeat end open on renameStuffIn(theFolder) set ix to 0 tell application "Finder" set folderName to name of theFolder set allNames to name of every item of theFolder repeat with aName in allNames set thisItem to item aName of theFolder set ix to ix + 1 set newName ...