Tim Bray (Textuality) provided a report from the front lines of the XML specification development. The first XML specification was printed in November and announced at the GCA's SGML '96 to an enthusiastic audience. The SGML Working Group rallied around the effort and the two groups have worked to ensure that there is no daylight between them.
A draft corrigendum from WG8 is now available, clarifying various points in ISO 8879. The XML WG is officially organized under the W3C. W3C did not talk much about the XML effort, even when asked if HTML would become self-extending. As interesting as XML is, if things are going to happen it will be because a big vendor gets involved -- and Microsoft did. They have already announced use of XML in their support for Channel Definition Format (CDF). They have also stated publicly that they have programmers working on XML. In PC Week it was stated that Internet Explorer 4 preview 3 will have XML support. In March 1997, Netscape said never go near XML. Netscape have now announced that they are considering it, and will have representation on committee.
Bray talked about what it means to do XML on the Web. First, take an existing HTML browser, which currently ignores tags it doesn't recognise, and apply style to those tags it doesn't know. This is very difficult, non-trivial to add. A second way would be to imbed fragments of XML in an HTML document. A third possibility would be to bypass HTML legacy completely and create lightweight version of the browser that does some stylesheeting and a way to say how to treat XML elements as relative to HTML elements.
Bray's prediction for the probability of using any of these three methods: 25-50% for use of existing browsers to handle other stuff; small chunks 100%; lightweight model - very high. Bray also noted that the hyperlinking specification has been getting rave reviews, even though there are still some problems. The W3C is pushing extensions. The machinery defined by the specification would work with SGML and HTML; it is not tied to XML. As for the XML specification's official status, while he thinks the specification will proceed through the various approval levels, the specification approval process within W3C is being revamped. He summarized the status of the three parts of the specification:
There is less consensus in this area. Some subsetting of DSSSL has been done, but cascading style sheets (CSS) is already here and is supported in some browsers already. Whilst it is assumed that CSS will be supported at a minimum, CSS is already showing signs of stress. Bray also talked about Lark, his XML processor, and of some of the issues in writing it. The tutorial the next day talked about the details of building an XML processor.
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