XSL Considered Harmful
Declaration of War
Two weeks ago XML.com published an article by G. Ken Holman, What's the Big Deal With XSL?, in which the author expressed his "perplexity about the perceived controversy over XSL." I expressed my surprise and disappointment to XML.com that one point of view in this "perceived controversy" had been given such a full airing while nothing had been heard from the other side. I asked for equal time and I was given it.
I am going to start out with a brief and perhaps stark statement on the subject, my "declaration of war". It is high time we get to the heart of the matter.
XSL, a "sometime in the future" technology, full of beautiful (if vague) prognostications about its "power" and "richness", offers no useful improvement in capability over current and implemented full W3C Recommendations for stylesheets and transformation.
XSL has no role to play in the evolution of web technology into the "new desktop" as it does not support interactive documents.
XSL is a great danger to a major objective of XML, the inclusion of semantic information in Web pages, as it replaces XML elements annotated with formatting information by XSL formatting objects.
XSL is the most hideous and unwieldy language imaginable and stands absolutely no chance of acceptance by the web community.
XSL advocacy has blurred the focus of the W3C, by introducing competing standards for styling and transformation, and set back by at least two years the goal of vendor-independent, semantically rich "open information highway", by undermining support for existing standards such as CSS and the DOM.
This is really all I have to say, but if any one of these points is true, that is a damning case against XSL. I have invited and continue to invite, in good faith and with an open mind, XSL advocates to counter these arguments.
In the remainder of this article I will elaborate on these five fatal flaws of XSL and present an application which will give you the chance to directly compare XSL to the transformation and styling technologies supported by current W3C Recommendations. But first, The Challenge:
Anything XSL can do in the Web environment, I can do better using technologies supported by current W3C Recommendations.
Of course, what is "meaningful" in the Web environment is open to a variety of interpretations. Therefore, the subject of the challenge should be one that the XSL camp and I agree is meaningful.
I am also ready to make this bet a little bit more than an academic exercise. If I lose, I will pledge that I, and my crack mozilla development team, will assist in implementing XSL in the mozilla open source project. If my opponents lose they will agree to desist from XSL advocacy, vote against an XSL Recommendation if they are members of the W3C, and will join me in calling for full, flawless, and unequivocal vendor support of CSS1 and CSS2, DOM Level 1, and XML 1.0 as the very first and top priority of the web community.
Next we explore the five fatal flaws of XSL.