XML documents merger ahead

The World Wide Web Consortium (W3C) on Monday recommended XML Inclusions (XInclude) Version 1.0, a specification designed to replace awkward work-arounds for combining XML documents.

"Inclusion is the ability to reuse content, which lets me take something like a copyright statement and include it on all my company's XML documents," said Philippe Le Hegaret, the W3C's architecture domain leader. "Without an inclusion mechanism, you have to copy and paste, and this lets you just reference it."

XML authors have other, more cumbersome ways of merging documents without the new specification. The most widely used relies on the document type definition (DTD), a server-based set of instructions that helps computers interpret XML documents and determine how their elements interact.

But the W3C is trying to move XML away from DTDs. The group since 2001 has recommended the use of XML Schema instead. It has mandated the use of XML Schema in other recommendations such as SOAP (Simple Object Access Protocol) 1.2 and WSDL (Web Services Description Language).

If widely adopted, XInclude could prove another nail in the DTD's coffin.

"XML Schema will ultimately replace DTDs," Le Hegaret said. "By adding this inclusion mechanism, we will rely less and less on it."

The W3C's XML Core Working Group, part of the XML Activity, published Monday's recommendation. XInclude's editors are Jonathan Marsh of Microsoft and David Orchard of BEA Systems.