Why? Because learning XML is like someone coming along and giving you a big manual on how to build a highway. They'd tell you how wide the roads should be, where the signs need to go, what color the lines down the middle have to be. But, eventually, you'd ask someone, "Say, what does this sign mean, anyway?", and your boss would tell you that he doesn't really know. "It all depends on how the driver interprets the sign," he'd say. "There really aren't any people with cars that can drive on this road yet, so we're pretty sure this sign here's gonna mean "Stop"--but that really depends on who winds up driving the car."
This is because there really aren't a lot of browsers that interpret XML--even for those that do, there are vast differences. If you've got a concrete set of tasks that you want XML to accomplish, and that you know HTML and company can't do, you've got solid, understandable examples with which to work. But, if you don't, you could be up the creek.
And this presents a lot of challenges for the XML book writer--how the heck do you explain a technology that, in many ways, isn't quite done yet?
Enter Just XML.
Unlike most programming-guide authors, John Simpson is extremely chatty and spends a lot of his time walking you through the concepts behind XML. Using a fictional B-movie database as an example of XML programming, Simpson walks you through the vagaries of XML with good, clean writing. He has a very good ear for solid metaphors, and he's also extremely good at anticipating the questions that a novice might have. His conversational tone even extends to discussing where XML's specifications fall through; to lighten things up, he even gives numerous plot summaries and reviews of B-movies.
But the book has some fairly annoying flaws. For one thing, the organization's a little backward--the code for the movie database is at the back of the book, instead of up front, and Simpson sometimes spends more time explaining why things work than what they're supposed to be doing. If you're not sure why you'd want to use a particular XML feature at this point in the document, you might get baffled. And the very informal nature of this book is sure to annoy serious programmers who just want the facts.
But, when it comes down to it, the XSLT chapter is golden--the explanations are as good as they're going to get for a kind of vague topic--and, frankly, I'd recommend it to anybody who needs an idea of what XML is for and what it can do. But, once you get that down, you'll probably need another set of XML tutorials to nail down your XML syntax knowledge. Recommended. --William Steinmetz