There have been a few posts in the BBS recently about creating pre-defined folder hierarchies. The most obvious method, for an AppleScripter, would be a recursive process involving the Finder. But the same thing can be achieved with a single Unix ‘mkdir’ command. This is incredibly fast and is (for a Unix command) quite easy to understand.
If you have a folder “a” on your desktop, the following will create a folder “b” inside it:
set desktopPath to POSIX path of (path to desktop)
set mkdirStr to "mkdir " & desktopPath & "a/b/"
--> "mkdir /Users/username/Desktop/a/b/"
do shell script mkdirStr
If there’s no folder “a” then the script will error. But with the addition of a parameter ‘-p’, the script will create both “a” and “b” if necessary. In fact, it will create any folder in the supplied path that doesn’t already exist.
set desktopPath to POSIX path of (path to desktop)
set mkdirStr to "mkdir -p " & desktopPath & "a/b/c/d/e/"
--> "mkdir -p /Users/username/Desktop/a/b/c/d/e/"
do shell script mkdirStr
The ‘man’ page for ‘mkdir’ doesn’t reveal that, besides being able to create folders to any reasonable depth, the command can also handle width, and can create multiple sibling folders in the same directory. The following creates folders “b”, “c”, “d”, and “e” in the top level of folder “a” (and creates “a” too if necessary).
set desktopPath to POSIX path of (path to desktop)
set mkdirStr to "mkdir -p " & desktopPath & "a/{b,c,d,e}/"
--> "mkdir -p /Users/username/Desktop/a/{b,c,d,e}/"
do shell script mkdirStr
Although the brace syntax looks like an AppleScript list, there should be no spaces after the commas. There’s another trick you can do with braces here. If the left brace comes immediately after a slash or a comma, as above, then the text between the commas represents the names of the subfolders to be created at that level. But if the left brace comes immediately after some text, then the stuff between the commas is suffixed to that text in the names of all the created folders. (Or, if you prefer, the text is prefixed to the stuff between the commas.) This can save some typing if you want siblings’ names to begin with the same text:
set desktopPath to POSIX path of (path to desktop)
-- (Note the single quotes round the space to mark it as part of the name.)
set mkdirStr to "mkdir -p " & desktopPath & "a/Chapter' '{1,2,3,4}/"
--> "mkdir -p /Users/username/Desktop/a/Chapter' '{1,2,3,4}/"
do shell script mkdirStr
--> Folders "Chapter 1", "Chapter 2", "Chapter 3", and "Chapter 4" are created in folder "a"
Similarly, if the right brace is followed immediately by text, that text is suffixed to the stuff between the commas. All this cleverness is very versatile. It can be nested and combined in several ways to define an entire hierarchy, and can provide hours of experimental fun:
-- (Other lines omitted for brevity.)
set mkdirStr to "mkdir -p " & desktopPath & "a/Chapter' '{1,2,3,4}c/"
--> In folder "a": folders "Chapter 1c", "Chapter 2c", "Chapter 3c", and "Chapter 4c".
set mkdirStr to "mkdir -p " & desktopPath & "a/Chapter' '{1,2,3,4}/c/"
--> In folder "a": folders "Chapter 1", "Chapter 2", etc., each containing a folder "c".
set mkdirStr to "mkdir -p " & desktopPath & "a/Chapter' '{1,2/c,3,4}/"
--> In folder "a": folders "Chapter 1", "Chapter 2", etc., only "Chapter 2" containing a folder "c".
set mkdirStr to "mkdir -p " & desktopPath & "a/{Chapter' '{1,2/c,3,4},Index}/"
--> In folder "a": four "Chapter" folders and an "Index" folder. "Chapter 2" contains a folder "c".
There’s an upper limit to the length of the mkdir string, but you’re unlikely to hit it. A hierarchy-duplication script I wrote last year can happily recreate the 895 folders in my Library folder with one ‘mkdir’ call. It takes a few seconds for the script to collect the information and think about the string, but once that’s done, the entire duplicate hierarchy is created almost instantaneously. If I were more au fait with Unix, the infomation gathering might be quicker too. 
