- From: Axel Polleres <axel.polleres@deri.org>
- Date: Wed, 11 Feb 2009 11:57:20 +0000
- To: Jos de Bruijn <debruijn@inf.unibz.it>, "Public-Rif-Wg (E-mail)" <public-rif-wg@w3.org>
Jos de Bruijn wrote: >>> Re: the first editor's note in section 3.1.1 >>> >>> I believe the predicates should depend on a specific domain, and should >>> be undefined if it is not the case that both arguments are in the same >>> value space. >>> This only becomes an issue, of course, if we decide to adopt these >>> predicates, which is not something I support. >>> >>> <snip/> >>> >>>> 1) As noted in the editor's note, it seems to me that >>>> >>>> pred:literal-equal >>>> >>>> is redundant. If that is untrue, let me know. >>> this is not true (at least it should not be). Equality in XML schema is >>> not the same as identity. >>> >>>> Now here goes an example for the problem case, assuming disjoint >>>> datatypes decimal and double (please confirm),: >>>> pred:numeric-equals("1"^^xs:double , "1"^^xs:decimal) = t >>>> pred:literal-equals("1"^^xs:double , "1"^^xs:decimal) = f >>> literal-equals should behave the same as numeric-equals on numbers. It >>> seems to me that you made a mistake in the definition. >> I tried to write down what we discussed, to get a better understanding >> ofg what we want... it was/is not clear to me what you mean by "mistake" >> at this point. If you think that literal-equals should do promotion, >> that is one point of view, there might be others. > > Okay, then we have different ideas about the discussion was about. I > thought the discussion was about replacing the individual comparison > operators with one comparison operator for all datatypes. the discussion had two parts: i) defining generic comparison predicates ii) deciding whether these can replace the specific ones as for the latter, numeric-equals is an obstacle at the moment. > It seems that now that you are proposing to add new comparison operators > that are in fact quite different from the individual comparison > operators we currently have. Are you proposing to remove the individual > comparison operators or do you want to keep them? I personally am not decided yet on this issue, I think we need to discuss it. If we want replacement (which indeed I was hoping we could achieve). I see three options: - we keep both the generic and the specific equalities. - we remove the specific comparison predicates and accept that we don't cover the specific functionality of numeric-equal that includes promotion and enable this "feature" only via explicit casts. - we remove the specific comparison predicates and change the definition of literal-equals to comprise numeric-equal... I don't like this, because it may hamper extesibility of the definition of literal-equals to other datatypes. Axel -- Dr. Axel Polleres Digital Enterprise Research Institute, National University of Ireland, Galway email: axel.polleres@deri.org url: http://www.polleres.net/
Received on Wednesday, 11 February 2009 11:58:01 UTC