Mac OS X Leopard - ARCAism

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CHAPTER 23 MAC OS X AUTOMATION WITH AUTOMATOR AND APPLESCRIPT
All the operators have a long list of synonyms. Aside from is, you could say equals or use
the mathematical equals sign:
else if _waitInSeconds is _timeoutInSeconds then
error number -128
Error -128 means “User canceled.” This will basically press the Cancel button for you after
20 seconds. Although AppleScript errors in practice are often obtuse, the language actually has
decently robust error handling, including try blocks and targeted error handlers based on both
the type of error and the object that caused it. Errors can include numeric codes, text descriptions,
partial results, and more.
Since if statements and repeat statements are multiline, they require end statements.
end if
end repeat
We are, admittedly, no AppleScript gurus. JavaScript has access to things like links, but
there’s no way we know of to pass an array of links from JavaScript back to AppleScript without
writing some seriously funky JavaScript. Since that’s not what we’re going for, we’re going to
parse the links out manually in AppleScript. If it isn’t obvious, there are several different ways
to do this.
The Google image results page returns a massive string:
set _searchResults to source of document 1
Strings in AppleScript are basically lists. Aside from typical components such as paragraphs
and words, strings have an amorphous text items component, which is defined as the components
of a string as separated by the global text item delimiter.
NOTE Although there is technically a list of delimiters, it’s a list of one. Thus, we talk about the
text item delimiter, but the actual keyword is pluralized. We set the delimiter to a single string,
but behind the scenes, AppleScript will coerce our string into a single-item list.
If you examine the raw source of a Google image results page, it’s not plain HTML but a
bunch of JavaScript and other goings on. The URLs we want are quoted as part of a commaseparated
list of parameters, so the easiest way to get at them is to split the string by the token
",".
However, strings in AppleScript are also quoted, so we have to escape the quotes within the
string with backslashes, setting the delimiter to "\",\"":
set AppleScript's text item delimiters to "\",\""
This converts the string _searchResults into the explicit list _rawResults, which we’ll loop
through to filter out the URLs:
set _rawResults to text items in _searchResults
Although we declared _searchResults in a different try block, it’s still in scope.
Since the text item delimiter is global, it is considered good form to set it back to the default,
which is the empty string, "":
set AppleScript's text item delimiters to ""
This is a different loop construct, which enumerates the list, assigning each of its members
to the named variable in turn:
repeat with _text in _rawResults