Re: the mechanism for signatures in RIF

Michael Kifer wrote:
> Dave Reynolds <der@hplb.hpl.hp.com> wrote:

>> Lexically then the WD1 description says:
>>
>> "Symbols of this sort have the form "XYZ"^^rif:uri, where XYZ is a URI 
>> as specified in RFC 3986."
>>
>> I don't think that is quite right. I think we want XYZ to be a 
>> URI-Reference (i.e. including optional fragment identifiers).
> 
> But RFC 3986 doesn't preclude fragment identifiers, e.g., http://foo#bar.
> Is it not true?

Indeed. I had meant to say "including relative references and optional 
fragment identifiers" but brain and fingers seem to have not been 
coordinated and missed out the important bit, sigh.

That RFC defines URI-references as "either a URI or a relative 
reference" and gives the syntax for relative references.

>> In at 
>> least the XML syntax, and possibly in the linear syntax, we also want to 
>> permit relative as well as absolute URI-References.
> 
> It is not clear to me whether relative URI references should be part of the
> logic (and unduly complicate it) or whether they should be treated as 
> syntactic sugar. 

Good point. They shouldn't really be part of the logic. We do need to 
specify that syntactic sugar but you are right it would be better to 
keep that out of the sort definition.

>> Turning to rif:localSymbol, if this is really needed then it would have 
>> the same lack of domain assumptions as rif:uriSymbol (indeed presumably 
>> it would generally have exactly the same domain).
> 
> In my view, the whole reason for local symbols is to make them completely
> hidden so that they won't interfere with any other symbol. So, as I
> mentioned before, I expect the domain of local symbols to be disjoint from
> the rest.

Disjoint domains seems to be a stronger restriction than needed just for 
scoping. In a RIF dialect with equality could you not imagine cases 
where an individual denoted by a local symbol could be deduced to be 
equal to an individual denoted by a global symbol?

Dave

Received on Tuesday, 27 March 2007 13:04:01 UTC