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AppleScript - the Definitive Guide
AppleScript as a language and development environment has some terrible problems, and I applaud Neuburg for not trying to hide them away. Personally I love the power the language can provide, while loathing it for it's "English-like" syntax and the problems inherent in having most of the language defined in differing ways in different applications.
One of Applescript's problems is that it is difficult to teach, as you almost have to understand everything before you can know anything. Unfortunately that problem is reflected in this book. Neuburg constantly finds himself having to resort to the "believe me for now, I'll explain later" strategy throughout the book.
The book is broken up into four sections: "AppleScript Overview," "The AppleScript Language," "AppleScript In Action," and several appendices.
"AppleScript Overview" is a well written look at what AppleScript is, what it is good for and how to use it. Chapter 3, "The AppleScript Experience" is an impressive warts-and-all walk-through of the author developing an AppleScript to solve the problem of renaming files to conform to a particular standard using FrameMaker and the Finder. It is here that the reader will first see the problems inherent with AppleScript as Neuburg battles with incomprehensible dictionaries, unknown object models and uncommunicative error messages to build his script.
Part II, "The Applescript Language," is the 200-page core of this book. Neuburg provides a detailed and comprehensive look at every detail of AppleScript's syntax and semantics. The first chapter of this section, "Introducing AppleScript" contains a marvelous section entitled 'The "English-likeness" Monster' that is a short, sharp (and entirely justified) attack on the problem of AppleScript's attempt to be English-like in syntax.
In the rest of this section Neuburg provides an exceptional survey of the language. I personally appreciated his examination of the intricacies of type coercion and the exotic scoping rules. He has also taken the time to write and elaborate a large number of small pieces of code to demonstrate gotchas and tricks throughout the language.
It is this section that truly separates this book from every other AppleScript book I have previously read -- it is a masterful guide to the language.
Part III is a concrete path towards writing your own scripts. Neuburg starts by examining application dictionaries in depth. The real power of AppleScript lies not in the language itself but in the ability to use language extensions built in to other applications. This also becomes a huge flaw when the only documentation you get is in the application dictionary. As Neuburg puts it "One purpose of the dictionary is to show the human user how to speak AppleScript to a scriptable application in order to drive that application. But a dictionary, by its very nature, is not completely adequate to this task." He then goes on to explain the flaws.
The first appendix is a dump of the AppleScript Suite from AppleScript's 'aeut' resource. This is the core of the language usable everywhere. The second Appendix is a good, useful guide to tools and resources for the AppleScript programmer.
Taken as whole, this is a great book for the AppleScript programmer, both beginner and expert. It has a good writing style, has been well edited and well constructed. Neuburg may be putting in too many forward references, though. Other reviewers, particularly those newer to AppleScript, have called the book frustrating and confusing. I think this may be due to both the high information density in this book and Neuburg's fast introduction to topics that are better explained later in the book. If you are a newcomer to programming and AppleScript then this may be daunting.
If you are new, however, this is still an excellent volume but you may have to force yourself to finish it and then go over at least Part I and II again to truly understand the language. It would probably be a good idea to start trying to build your own scripts after the first read through. I must say, that after taking a good hard look at the way the book has been constructed and ordered I couldn't really come up with a better way that wouldn't have doubled the size of the book.
Visit the O'Reilly web page for the book if you would like to see the Table of Contents or grab an example chapter.
Neuburg has said "My approach is not to rely on documentation, ... but to bang away at the language itself, testing and experimenting, trying to deduce the underlying rules" and this approach has certainly borne fruit in this volume. For all it's minor flaws you cannot say, as may be true of many other tech books, that it is a rewrite of the documentation. He has approached the problem from a different direction and given us a book that offers an excellent guide to the language.
I would recommend it to all Macintosh owners as the perfect way to unleash another powerful aspect of your system. For people who have no AppleScript or programming experience who want to be totally spoon fed this book is probably only a 5, for people with a little AppleScript experience, a fair amount of programming experience and a willingness to stick through to the end this book is probably a 9. It is certainly the best book on AppleScript I have seen.
You can purchase AppleScript - the Definitive Guide from bn.com. Slashdot welcomes readers' book reviews -- to see your own review here, read the book review guidelines, then visit the submission page.
A book on a language can be wonderful but that doesn't help when the language is flawed. Perhaps in the days of Mac OS =9 people would have use it. Now, with Mac so close to Unix (via BSD) I would have thought that it won't be long until a Glade or QT Designer style program with C or C++ will be the driving force in compiled programming and ports of Perl and Python in interpretted languages.
Is there a case for Applescript to answer?
I am not trying to start and argument, and I do not think OS evolution will irradicate a language, maybe just reduce it's use. After all a system (Mac) dependent language is not a useful as multiplatform code.
As one of the original designers of AppleScript, I feel compelled to mention that the syntax issue is a complete red herring. The language was originally designed to have replaceable syntax, and it could switch, in real time, between dialects with radically different syntax. The same routine would display in different language localizations, or different syntax forms, depending on user preference.
Apple had a Japanese dialect and a C-like dialect built during the development phase. These were never tested enough to release, primarily because of a management decision to shift a lot of the team over to work on OpenDoc after AppleScript's first release.
However, that said, it can be terribly frustrating to figure out the syntax of the current system. This is because a number of language extensions have been built through a mechanism known as OSAX extensions, over the years. The language elements which come from applications work pretty well, because there's a block structure which wraps them into easily detectable blocks. OSAXen, though, tend to interact globally with the syntax of everything, and a lot of the OSAXen have really gnarly syntax that causes all sorts of unforeseen interactions. Unfortunately, the core language was missing some important features, and OSAXen were the easy way to add some of that back, so it got completely out of hand rather early on.
The original team never imagined that the current syntax would be the only one. Quite the contrary, we viewed it as a syntax that HyperCard users would find familiar, but many other folks would find rather verbose.