- From: Axel Polleres <axel.polleres@deri.org>
- Date: Tue, 06 May 2008 14:41:00 +0100
- To: Michael Kifer <kifer@cs.sunysb.edu>
- CC: "Public-Rif-Wg (E-mail)" <public-rif-wg@w3.org>
Michael Kifer wrote: >> Michael Kifer wrote: >>> 1. Curie, <...> >>> My main concern with context sensitivity is that it will confuse people >>> (like it did several members of this group) to think that the stuff after >>> ^^ are constants by themselves. This requires that we explain things >>> carefully and, possibly, will cause more confusion. The more context >>> sensitivity we have, the more explaining we have to do, and no amount of >>> explanation might be enough. >>> >>> My strong preference is to limit context sensitivity or completely >>> eliminate it, but in the spirit of reconciliation I am also willing to go >>> with majority :-) >>> >>> By the way, I did not understand what PNAME_LN and PNAME_NS are. I guessed >>> that the latter is the foo:bar thingie, but what is LN? >> see the resepctive productions at >> http://www.w3.org/TR/rdf-sparql-query/#rPrefixedName >> http://www.w3.org/TR/rdf-sparql-query/#rPNAME_LN >> http://www.w3.org/TR/rdf-sparql-query/#rPNAME_NS > > OK. Perhaps somebody can explain this a bit more? It looks like that syntax > allows things like prefix: and abc...de. > > >>> 2. PREFIX. >>> I do not like the syntax PREFIX(...), since it suggests that this is a >>> fact-formula. >> If it causes ambiguity then we need to change it, indeed. >> >>> However, I am ok with it as a directive (with the same syntax >>> as you suggest) in the preamble of the document, along with Import and >>> whatever else we'll end up having there. >> fine for me. > > ok > >>> 3. Regarding your response to Hassan suggesting " instead of \", I do >>> not understand your reasoning. You were so gang-ho on brevity and now >>> suddenly 6 characters instead of two? >>> >>> If you want to use entities, like ", then why not use them >>> throughout? That is, instead of rif:iri use &rif;iri, and we are done away >>> with context-sensitive curies and all that. (This is what I was proposing >>> from the very beginning except that I was suggesting to use : instead of >>> &...;.) >> Probably, you, Sandro, and Hassan are right that XML entities in the >> presentation syntax are confusing. Alternatively, escape sequences like >> defined in SPARQL seem to be better: >> http://www.w3.org/TR/rdf-sparql-query/#grammarEscapes >> http://www.w3.org/TR/rdf-sparql-query/#codepointEscape >> >> Does that look more reasonable to you? > > SPARQL escapes? These look to me like good old C language escapes. > These are fine, but do not assume that the world began with Sparql. ??? of course not. >> I agree that we should focus on the XML syntax issues now as suggested >> in Sandro's mail. But I guess the SPARQL escaping mechanism should do >> for the moment... I assume hey spent some thinking on it and in case >> there are problems, we can revisit this point upon feedback. >> >> best, >> Axel >> >>> --michael >>> >>>> Sorry, this might be unconvenient, but due to an urgent meeting whch I >>>> cannot shift, I have to pass on tomorrow's telephone conference. >>>> >>>> So, in order not to hamper progress for DTB, I suggested several options >>>> to vote over concerning the points in my mail at [1]. >>>> >>>> http://lists.w3.org/Archives/Public/public-rif-wg/2008Apr/0194.html >>>> >>>> 1) CURIEs: As for 1) there were extensive discussions on the >>>> mailinglists, it seems that [2] is kind of a minimalistic proposal >>>> whereas [3] is richer. I haven't seen a grammar for [2] yet, so let me >>>> put both options on the table again. >>>> >>>> a), cf. [3] >>>> >>>> ANGLEBRACKIRI ::= '<' IRIRef '>' >>>> >>>> STRING ::= '"' ANYSTRINGWITHOUTQUOTES '"' >>>> >>>> CURIE ::= PNAME_LN | PNAME_NS >>>> >>>> Const ::= ANGLEBRACKIRI >>>> | CURIE >>>> | STRING^^ANGLEBRACKIRI >>>> | STRING^^CURIE >>>> >>>> b), cf. [2] >>>> >>>> ANGLEBRACKIRI ::= '<' IRIRef '>' >>>> >>>> STRING ::= '"' ANYSTRINGWITHOUTQUOTES '"' >>>> >>>> CURIE ::= PNAME_LN | PNAME_NS >>>> >>>> Const ::= CURIE >>>> | STRING^^ANGLEBRACKIRI >>>> | STRING^^CURIE >>>> >>>> >>>> Comparison between a) and b): The only difference is that b) doesn't >>>> allow ANGLEBRACKIRIs as Consts, thus making it N3 incompatible, but >>>> well. Both are context-sensitive. There were some other discussions >>>> introducing some form of "aliasing" [2,4], but since I didn't see a >>>> grammar for this and thus it is unclear whether these would introduce >>>> ambiguity, I suggest to keep it out. >>>> >>>> I suggest to vote between these two, my own vote is for a), though I am >>>> willing to obey a majority vote for b). I personally would be unhappy >>>> with N3 incompatibility [5,6] when voted for b), since none of the >>>> arguments given so far were technical in the sense of that there would >>>> be any problem with the grammar for a). For an additional argument, see >>>> also 4) below. >>>> >>>> 2) FULL URIs for RIF (see also [7]) >>>> >>>> From the original proposals, the following 2 seem to have "survived" >>>> the discussions so far: >>>> >>>> a) define own prefixes (separate for functions and predicates): >>>> >>>> http://www.w3.org/2007/rif-builtin-predicates#numeric-equal >>>> >>>> http://www.w3.org/2007/rif-builtin-functions#concat >>>> >>>> c) reuse XPath/Xquery fn: prefix (problem: not prefix defined for op: we >>>> still would need to invent one): >>>> >>>> http://www.w3.org/2005/xpath-??????#numeric-equal >>>> >>>> http://www.w3.org/2005/xpath-functions#concat >>>> >>>> I personally prefer a) and suggest to >>>> >>>> PROPOSE: We define own namespace prefixes >>>> PREFIX("pred", "http://www.w3.org/2007/rif-builtin-predicates#"). >>>> PREFIX("func", "http://www.w3.org/2007/rif-builtin-functions#"). >>>> for RIF builtin functions and predicates >>>> >>>> >>>> 3) The handling of errors seems not to be anything we need to discuss >>>> over again. >>>> >>>> 4) Additionally, I suggest to introduce: >>>> >>>> PREFIXDef ::= ' PREFIX(' PNAME_LN , STRING ') .' >>>> >>>> for the prefix definition in the presentation syntax. >>>> Whether this expands to Qnames or entitties in the actual XMLificaiton >>>> is a separate issues [8,9] and not important for stabilitzing DTB, it >>>> seems. In doubt, I am with Michael here [9] and suggest that in a >>>> translator to XML PREFIXDef translates to an ENTITY definition... but >>>> that's an implementation detail anyways, one could likewise simply >>>> expand all CURIEs in the XML.... The only problem with that is that if >>>> you want to translate *BACK* to presentation syntax again, you will end >>>> up with something ugly, if we go for option b) on 1) above. >>>> >>>> >>>> Axel >>>> >>>> >>>> >>>> [1] http://lists.w3.org/Archives/Public/public-rif-wg/2008Apr/0194.html >>>> >>>> [2] http://lists.w3.org/Archives/Public/public-rif-wg/2008May/0015.html >>>> >>>> [3] http://lists.w3.org/Archives/Public/public-rif-wg/2008Apr/0203.html >>>> >>>> [4] http://lists.w3.org/Archives/Public/public-rif-wg/2008May/0019.html >>>> >>>> [5] http://lists.w3.org/Archives/Public/public-rif-wg/2008May/0005.html >>>> >>>> [6] http://lists.w3.org/Archives/Public/public-rif-wg/2008May/0008.html >>>> >>>> [7] http://lists.w3.org/Archives/Public/public-rif-wg/2008Apr/0196.html >>>> >>>> [8] http://lists.w3.org/Archives/Public/public-rif-wg/2008May/0011.html >>>> and following thread. >>>> >>>> [9] http://lists.w3.org/Archives/Public/public-rif-wg/2008May/0027.html >>>> >>>> >> >> -- >> Dr. Axel Polleres, Digital Enterprise Research Institute (DERI) >> email: axel.polleres@deri.org url: http://www.polleres.net/ >> >> rdfs:Resource owl:differentFrom xsd:anyURI . >> > -- Dr. Axel Polleres, Digital Enterprise Research Institute (DERI) email: axel.polleres@deri.org url: http://www.polleres.net/ rdfs:Resource owl:differentFrom xsd:anyURI .
Received on Tuesday, 6 May 2008 13:41:35 UTC