- From: Polleres, Axel <axel.polleres@siemens.com>
- Date: Thu, 12 Apr 2012 13:46:47 +0200
- To: Andy Seaborne <andy.seaborne@epimorphics.com>, "public-rdf-dawg@w3.org" <public-rdf-dawg@w3.org>
Thanks, Andy, For the moment, we can live without it for our use case, would anybody support to put propagating all op:... operator delegations for basic arithmetics from Xpath/Xquery operators on the future work items list? > > It's probably too much of a burden to add it now, but > "nice-to have" > > for my use case would be > > Slippery slope! > > We would have to add required support for xsd duration > hierarchy (xs:dayTimeDuration, xs:yearMonthDuration). Yeah, understood. I agree that adding some, but not all op:... delegations would seem arbitrary, and adding all at this stage looks like a potential source for trouble and as you said, additional impl. Burden for compliance... > (Disclosure: ARQ does g* and some of durations but not all > arithmetic on datetimes - someone contributed the duration support) ... Great, that might solve my use case for the moment, will look into that. > > op:add-dayTimeDuration-to-dateTime > > FYI: Only applies to DT+dayTimeDuration, not the other way round. Understood, that's why I thought is might be convenient for either xsd:dateTime + xsd:dayTimeDuration or xsd:dayTimeDuration + xsd:dateTime Both to op:add-dayTimeDuration-to-dateTime() but switching operators for the latter. Anyways, as said above, can live without it being in the current standard. Cheers, Axel > -----Original Message----- > From: Andy Seaborne [mailto:andy.seaborne@epimorphics.com] > Sent: Thursday, 12 April 2012 12:09 PM > To: public-rdf-dawg@w3.org > Subject: Re: datetime-difference > > > On 12/04/12 10:50, Polleres, Axel wrote: > > Hi, > > > > </chair-hat> > > > > > > just as I was stumbling over it something for the wish-list... > > > > We need datetime-difference for some use case. > > > Was that ever considered in previous discussions in the > functions-library? > > Yes. > > 1/ You can do it by operator extension. > 2/ The decision was not to require all of XSD (datatypes, > functions) in core SPARQL. > > See also charter for LDP-WG. > > > I am looking at the XPath arithmetics delegation in Table "SPARQL > > Binary Operators" in Section 17.3 of the query doc, cf. > > www.w3.org/TR/sparql11-query/ > > > > > > It's probably too much of a burden to add it now, but > "nice-to have" > > for my use case would be > > Slippery slope! > > We would have to add required support for xsd duration > hierarchy (xs:dayTimeDuration, xs:yearMonthDuration). > > And xs:g*? -- probably more generally useful. > > Next step is xsd:time ... > > (Disclosure: ARQ does g* and some of durations but not all > arithmetic on datetimes - someone contributed the duration support) > > > > > 1) delegating "-" > > to > > > > op:subtract-dateTimes ( > > http://www.w3.org/TR/xpath-functions/#func-subtract-dateTimes ) > > > > For > > > > xsd:dateTime - xsd:dateTime > > > > > > 2) delegating "+" > > > > to > > > > op:add-dayTimeDuration-to-dateTime > > FYI: Only applies to DT+dayTimeDuration, not the other way round. > > > > > for either > > > > xsd:dateTime + xsd:dayTimeDuration > > or > > xsd:dayTimeDuration + xsd:dateTime > > > > > > Best, > > Axel > > Implementation burden for compliance. > > Personally, don't care - I'll add as much as users want. > > Andy > >
Received on Thursday, 12 April 2012 11:47:29 UTC