- From: Pat Hayes <phayes@ai.uwf.edu>
- Date: Mon, 5 Nov 2001 18:45:29 -0600
- To: jos.deroo.jd@belgium.agfa.com
- Cc: w3c-rdfcore-wg@w3.org
>Brian McBride wrote: >> >> Dan Connolly wrote: >> > >> > [...] >> > >> > <rdf:Description rdf:about="#me"> >> > <shoeSize> >> > <integer decimalRep="10"/> >> > </shoeSize> >> > </rdf:Description> >> > >> > To fill in the details... let dt: >> > be the namespace of XML Schema primitive datatypes, >> > and let rdfs:str be a new property >> > that relates XML Schema datatype to strings; >> > it's unambiguous over each of the primitive datatypes; >> > in the case of dt:string, it's the identity relation. >> > >> > <rdf:Description rdf:about="#me"> >> > <shoeSize> >> > <dt:decimal rdfs:str="10"/> >> > </shoeSize> >> > </rdf:Description> >> >> >> This isn't the same as above is it? In your first example I could >>have extended >> it to read: >> >> <rdf:Description rdf:about="#me"> >> <shoeSize> >> <integer decimalRep="10" hexadecimalrep="A"/> >> </shoeSize> >> </rdf:Description> >> >> I don't seem to be able to do that with your second example. Are there >> advantages to that which you have written over: >> >> <rdf:Description rdf:about="#me"> >> <shoeSize dt:decimal="10"/> >> </rdf:Description> >> >> or if you want the type property explicit, we need to invent a URI >>for the value >> space of the xsd datatype: >> >> <rdf:Description rdf:about="#me"> >> <shoeSize> >> <eg:integer dt:decimal="10"/> >> </shoeSize> >> </rdf:Description> > >I really see advantages in DanC's proposal > >People often write > :s eg:shoeSize "10". > :s nav:date "2001-11-02". > :s nav:time "16:14". > :s nav:flightNum "1154". > :s nav:customerNumber "678". > :s apt:latitude "50-54N". > :s apt:longitude "004-32E". > :s apt:elevation "58M". >or in general > :s :p "ooo". >and I believe that is a shorthand for > :s :p [ rdfs:str "ooo" ]. >(I used to prefer rdfs:label instead of rdfs:str >but now I think that rdfs:str is a better name for >the property mapping a data value (that bNode) >to it's string representation) I have serious problems with this. For a start, why on earth would anyone say that latitude and longitude and elevation were *strings*? They clearly aren't strings, so this is just plain wrong. Second, suppose someone were to write an ordinary triple (all urirefs), eg aaa bbb ccc . then using the same reasoning, you could say that what they really meant was that there was a thing denoted by the uriref "ccc" which ... etc, and so write this instead as: aaa bbb [ rdf:uriref "ccc" ]. ie aaa bbb _:1 . _:1 rdf:uriref "ccc" . where of course rdf:uriref is the mapping that takes a thing and gives you the quoted string which, were you interpret it as a uriref, would denote that thing. Now, that is a damn silly suggestion, obviously, but it is EXACTLY analogous to this suggestion for literals. And I don't see why the literals version is any more sensible than the damn silly version. Pat >So that object is actually some thing (that bNode) >which has that particular rdfs:str representation. >The shorthand is convenient when no additional >description of that thing is needed. > >Now if we want to be more precise w.r.t. that thing, >we just describe it further i.e. > :s eg:shoeSize [ rdfs:str "10"; rdf:type dt:decimal ]. OK, but what if we also know that read in octal, the string would be "12", so that :s eg:shoeSize [rdfs:str "12"; rdf:type dt:octal ] and now we merge? >The real advantage I see is that > :s eg:shoeSize [ rdfs:str "10" ]. >can be entailed given that > :s eg:shoeSize [ rdfs:str "10"; rdf:type dt:decimal ]. >(and only in that direction) But that seems to me to be rather a dangerous entailment, since if we then assert that, say, the range of eg:shoeSize is an octal number, we will have a valid way to prove that 10=12. Pat -- --------------------------------------------------------------------- IHMC (850)434 8903 home 40 South Alcaniz St. (850)202 4416 office Pensacola, FL 32501 (850)202 4440 fax phayes@ai.uwf.edu http://www.coginst.uwf.edu/~phayes
Received on Monday, 5 November 2001 19:45:29 UTC