- From: KANZAKI Masahide <mkanzaki@gmail.com>
- Date: Tue, 7 May 2019 12:20:52 +0900
- To: Wouter Beek <wouter@triply.cc>
- Cc: SW-forum Web <semantic-web@w3.org>
- Message-ID: <CAHQ1n3Athijh9Ye+XX-EmmJ+quFXT1f4ZJCSpkWfhc+DYWnAbQ@mail.gmail.com>
Hello Wouter, Some XHTML codes could be parsed as RDF/XML while others cause parse errors, because RDF/XML has some constraints to be a "striping" (elements should represent node -- property -- node pattern). W3C RDF Validator can parse your example XHTML by rapping with <rdf:RDF..> and </rdf:RDF>. Actually, it had "Extended interface" (existed until 2013, but now missing), where an option "RDF is NOT enclosed in <RDF>...</RDF> tags (optional since 2004, eg. see many DOAP files)" was provided. Note the result shows a parse error claiming 'String data "some col 1" not allowed.' (Another popular parse errors include mixed content and unexpected attribute on property element) If the <td> element is something <td><span>some col 1</span><td> then the validator accepts it and returns triples as you expected. Ignoring some parse errors (good or bad), it would be possible to interpret arbitrary XHTML as RDF/XML. My RDF visualizer ignores them and seems to be able to handle most XHTML as RDF/XML [1] (check XML/RDF option, otherwise it would be interpreted as Microdata HTML). cheers, [1] https://www.kanzaki.com/works/2009/pub/graph-draw 2019年5月7日(火) 5:03 Wouter Beek <wouter@triply.cc>: > > Dear SW community, > > The RDF/XML 1.1 specification contains the following two phrases: > > When there is only one top-level node element inside rdf:RDF, the > rdf:RDFcan be omitted although any XML namespaces must still be > declared. > > The XML specification also permits an XML declaration at the top > of the document with the XML version and possibly the XML content > encoding. This is optional but recommended. > > Does this mean that many/all (X)HTML documents are also RDF/XML > documents? If so, there is much more RDF out there than I had > previously thought. In fact, RDF would be at least as popular as HTML > (contrary to common complaints from the SW community about RDF's > popularity). > > Specifically, does the above mean that the following document should > be parsed by a standards-compliant RDF/XML parser: > > ```xml > <?xml version="1.0" encoding="utf-8"?> > <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" > "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd"> > <html xmlns="http://www.w3.org/1999/xhtml"> > <head> > <title> > </title> > </head> > <body> > <table> > <tr> > <td>some col 1</td> > </tr> > </table> > </body> > </html> > ``` > > , resulting in the following RDF triples (serialized in N-Triples): > > ``` > _:genid1 <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> > <http://www.w3.org/1999/xhtmlhtml> . > _:genid2 <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> > <http://www.w3.org/1999/xhtmltitle> . > _:genid1 <http://www.w3.org/1999/xhtmlhead> _:genid2 . > _:genid3 <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> > <http://www.w3.org/1999/xhtmltable> . > _:genid4 <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> > <http://www.w3.org/1999/xhtmltd> . > _:genid3 <http://www.w3.org/1999/xhtmltr> _:genid4 . > _:genid1 <http://www.w3.org/1999/xhtmlbody> _:genid3 . > ``` > > --- > Best regards, > Wouter Beek. > > Email: wouter@triply.cc > WWW: https://triply.cc > Tel: +31647674624 > -- @prefix : <http://www.kanzaki.com/ns/sig#> . <> :from [:name "KANZAKI Masahide"; :nick "masaka"; :email "mkanzaki@gmail.com"].
Received on Tuesday, 7 May 2019 03:21:36 UTC