This past week the W3C announced the publication of a working draft of RDFa in XHTML: Syntax and Processing in their Semantic Web Activity News Weblog which includes an RSS feed. I include a Semantic Web/RDF Overview/Reference compilation via the link in my signature block. James
Thanks for posting this (particularly your signature). I've only had a skim-read so far but this is looking very helpful, particularly http://www.rdfabout.com/intro/ that was a few clicks into your signature. JR
Too bad it's going to be USELESS thanks to Microsoft not supporting REAL XHTML (as in XHTML served as an application of XML).
Internet Explorer doesn't support XHTML when served as an application of XML. Plain and simple. Try it for yourself. Create a proper XHTML page (with the XML encoding above the DOCTYPE, then use the application/xhtml+xml content META tag instead of text/html and see what happens (if you did it correctly, IE will not recognize the page and force a file download).
Not quite, Dan. The situation will be similar to the one that exists with present XHTML 1.0 as far as included XML content is concerned (served as application/xhtml+xml). However, associated rdf/xml content will be usable with XHTML+RDFa -- in fact I am doing that right now. The XHTML+RDFa Doctype is now cataloged and I have composed two Validated test pages (using my extant Home page as a template), one served as content type text/html and the other as content type application/xhtml+xml: both render associated rdf/xml files with no problem: XHTML+RDFa served as text/html XHTML+RDFa served as application/xhtml+xml Check RDF Validation results for the RDF/XML feed at the bottom of the pages and the RSS live feed. Note also the new XHTML/RDFa W3C Validation icon. I have also included the XML Stylesheet prolog element. James
Actually, Dan, specifying the content type in the Meta tag as application/xhtml+xml will not in itself result in the page being served as XML compliant XHTML -- the file association must be established in the server. The best way to check how any page is being served is to use the Web-Sniffer HTTP Request & Response Header Viewer -- specify Browser via the User agent window (Firefox 2 MAC is equal to Firefox 2 Windows) -- best to use the default settings. Do not rely on the content type notation in the W3C Validator -- previous results are held in cache for some time. You can also easily check serving information via the Firefox Tools drop-down. The entire process is depicted and explained in "Serving XHTML" in my signature block -- be sure to check http://jp29.org/testx.html. James
The XHTML 1.0 problem is depicted and explained in "Serving XHTML" in my signature block, juan-roman -- be sure to check http://jp29.org/testx.html. James
The Semantic Web is now on the fast-track at the W3C and we are being bombarded with a plethora of documents, position papers, recommendations, etc. XHTML+RDFa is obviously still experimental (RDFa in XHTML: Syntax and Processing is only a draft). I personally use RDF/XML online for producing my RSS feed and manipulating Dublin Core Metadata -- my major use of RDF is for categorizing, sorting, organizing, and micro-searching Roman coin collections, extracting metadata/data from my web pages. The vision of Tim Berners-Lee (inventor/creator of the WWW and Director of the W3C) is that the future direction of the Web lies with the Semantic Web as presently defined. I have my own opinions -- I may be completely wrong in my assessments and predictions, but here goes: At present I think the whole concept of the Semantic Web/RDF (and XHTML+RDFa?) is far too complex and hard to understand -- my experience has been that most people seem to roll their eyes in bewilderment when they even glance through a Semantic Web document -- sometimes their eyes glaze over. I think that the concept is going to be a hard sell to the Web Authoring Community anyway -- I also think all the documents are going to have to be extensively simplified before they are usable in a practical way. On the other hand, I think the Semantic Web will eventually become a powerful -- probably irresistable -- force, but not soon. Again, In my opinion, XHTML has been a mess from the start. As it stands in the draft of the Syntax and Processing document, RDFa in XHTML must be served as application/xhtml+xml -- there is not even an Appendix C (ala XHTML 1.0) to permit it being served as text/html. BTW that has not prevented the W3C from serving their Semantic Web (XHTML+RDFa) documents as text/html -- but I am sure they are just experimenting. Of course the big question is: When will Microsoft support Content (MIME) Type application/xhtml+xml in their IE Browsers? Until it does (doesn't seem likely soon) XHTML+RDFa (like "real" XHTML 1.0) will not be universally usable. Again, XML/RDF will render in XHTML+RDFa if it is externally linked (as it will in XHTML 1.0 served as text/html for that matter). James
I have now installed on my Home Page a depiction, with live hyperlinks, of how this content-negotiation page is being served: Content (MIME) Type depiction via HTTP Request and Response Header Viewer for a representative selection of User-Agents (Browsers) - included is source code display for page Header examination. James