XSLT, 2nd Edition

XML Standards

When we talk about writing stylesheets, we’ll work with two standards: XSLT and XPath. XSLT defines a set of primitives used to describe a document transformation, while XPath defines a syntax for describing locations in XML documents. When we write stylesheets, we’ll use XSLT to tell the processor what to do, and we’ll use XPath to tell the processor what document to do it to. Both standards are available at the W3C’s web site; see http://www.w3.org/TR/xslt and http://www.w3.org/TR/xpath for more information.

There are other XML-related standards, of course. We’ll discuss them here briefly, with a short mention of how (or whether) they relate to our work with XSLT and XPath.

XML 1.0

The foundation upon which everything else is built. See http://www.w3.org/TR/REC-xml.

XML 1.1

You can find the XML 1.1 standard at http://www.w3.org/TR/xml11/.

The Extensible Stylesheet Language (XSL)

Also called the Formatting Objects specification or XSL-FO, this standard deals with rendering XML elements. Although most people think of rendering as formatting for a browser or a printed page, researchers use the specification to render XML elements as Braille or as audio files. (That being said, the main market for this technology is in producing high-quality printed output.) As of this writing, the latest version of XSL is 1.1. A couple of the examples in this book use formatting objects and the Apache XML Project’s Formatting Object to PDF translator (FOP) tool; see http://xml.apache.org/fop ...