Hi David It just reflects two different styles of URIs. Both are valid and both are in common use.
There is no difference in the role or meaning of the two different types of URI in terms of their use in RDF - but there are functional differences in how 'hash' and 'slash' URIs are dereferenced in Linked Data, because of the fact that browsers do not send the section of a URI after the hash to the server. See http://www.w3.org/wiki/HashVsSlash for a discussion. Cheers Bill On 10 Oct 2011, at 21:07, David Jordan wrote: > I have a related question. You see uses like the following: > @prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> . > @prefix dc: <http://purl.org/dc/elements/1.1/> . > > Some end in /, others end in #. What is the functional difference? > Or is one an older convention? > > > -----Original Message----- > From: Paolo Castagna [mailto:[email protected]] > Sent: Monday, October 10, 2011 2:57 PM > To: [email protected] > Subject: Re: Is this 'legal' Turtle? > > Hi Vadim, > thanks. > > But, is '#' a valid character in a qname? > http://www.w3.org/TeamSubmission/turtle/#qname > > Paolo > > Vadim Eisenberg wrote: >> Hi Paolo, >> >> The hash sign '#' starts a comment in Turtle - so the content after it >> is ignored by Turtle parsers. >> BTW, you can validate Turtle here - http://www.rdfabout.com/demo/validator/. >> >> Regards, >> Vadim >> >> On Mon, Oct 10, 2011 at 7:25 PM, Paolo Castagna < >> [email protected]> wrote: >> >>> Hi, >>> I am not sure whether this is legal Turtle or not: >>> >>> ------ >>> @prefix : <http://example.org/> . >>> @prefix foaf: <http://xmlns.com/foaf/0.1/> . >>> >>> :alice#me >>> a foaf:Person ; >>> foaf:name "Alice" ; >>> foaf:mbox <mailto:[email protected]> ; >>> foaf:knows :bob#me ; >>> foaf:knows :charlie#me ; >>> foaf:knows :snoopy#me ; >>> . >>> ------ >>> >>> When I try to parse it using Jena: >>> >>> Model model = ModelFactory.createDefaultModel(); >>> model.read(in, null, "TURTLE"); >>> >>> I get this exception: >>> >>> Exception in thread "main" com.hp.hpl.jena.n3.turtle.TurtleParseException: >>> Encountered " <PNAME_LN> "foaf:knows "" at line 9, column 5. >>> Was expecting one of: >>> ";" ... >>> "," ... >>> "." ... >>> >>> at >>> com.hp.hpl.jena.n3.turtle.ParserTurtle.parse(ParserTurtle.java:41) >>> at >>> com.hp.hpl.jena.n3.turtle.TurtleReader.readWorker(TurtleReader.java:21) >>> at >>> com.hp.hpl.jena.n3.JenaReaderBase.readImpl(JenaReaderBase.java:101) >>> at com.hp.hpl.jena.n3.JenaReaderBase.read(JenaReaderBase.java:68) >>> at com.hp.hpl.jena.rdf.model.impl.ModelCom.read(ModelCom.java:226) >>> [...] >>> >>> If I try to parse it using RIOT: >>> >>> RIOT.init() ; >>> Model model = ModelFactory.createDefaultModel(); >>> model.read(in, null, "TURTLE"); >>> >>> I get this exception: >>> >>> ERROR [main] (ErrorHandlerFactory.java:62) - [line: 9, col: 5 ] >>> Triples not terminated by DOT Exception in thread "main" >>> com.hp.hpl.jena.shared.JenaException: >>> org.openjena.riot.RiotException: [line: 9, col: 5 ] Triples not >>> terminated by DOT >>> at >>> org.openjena.riot.system.JenaReaderRIOT.readImpl(JenaReaderRIOT.java:132) >>> at >>> org.openjena.riot.system.JenaReaderRIOT.read(JenaReaderRIOT.java:79) >>> at com.hp.hpl.jena.rdf.model.impl.ModelCom.read(ModelCom.java:226) >>> [...] >>> Caused by: org.openjena.riot.RiotException: [line: 9, col: 5 ] >>> Triples not terminated by DOT >>> at >>> org.openjena.riot.ErrorHandlerFactory$ErrorHandlerStd.fatal(ErrorHandlerFactory.java:110) >>> at org.openjena.riot.lang.LangBase.raiseException(LangBase.java:201) >>> at >>> org.openjena.riot.lang.LangBase.exceptionDirect(LangBase.java:194) >>> at org.openjena.riot.lang.LangBase.exception(LangBase.java:187) >>> at org.openjena.riot.lang.LangBase.expect(LangBase.java:179) >>> at org.openjena.riot.lang.LangBase.expectOrEOF(LangBase.java:170) >>> at >>> org.openjena.riot.lang.LangTurtle.expectEndOfTriples(LangTurtle.java:45) >>> at >>> org.openjena.riot.lang.LangTurtleBase.triples(LangTurtleBase.java:246) >>> at >>> org.openjena.riot.lang.LangTurtleBase.triplesSameSubject(LangTurtleBase.java:206) >>> at >>> org.openjena.riot.lang.LangTurtle.oneTopLevelElement(LangTurtle.java:34) >>> at >>> org.openjena.riot.lang.LangTurtleBase.runParser(LangTurtleBase.java:132) >>> at org.openjena.riot.lang.LangBase.parse(LangBase.java:71) >>> at >>> org.openjena.riot.system.JenaReaderTurtle2.readWorker(JenaReaderTurtle2.java:34) >>> at >>> org.openjena.riot.system.JenaReaderRIOT.readImpl(JenaReaderRIOT.java:120) >>> ... 3 more >>> >>> I would be tempted to say that it should be treated as legal Turtle: >>> http://www.w3.org/TeamSubmission/turtle/#qname >>> >>> But it seems that '#' in the qname is treated a comment: >>> http://www.w3.org/TeamSubmission/turtle/#comment >>> >>> I tried to use the directive @base instead of @prefix : < >>> http://example.org/> . >>> I have the same exceptions in both cases. >>> >>> Perhaps the Turtle above is 'unusual' and I do not necessarily need >>> to use that. >>> But, since it occurred, I would like to understand if it's legal (and >>> we have a small bug) or not. >>> >>> Thanks in advance, >>> Paolo >>> >> > >
