- From: Axel Polleres <axel.polleres@deri.org>
- Date: Tue, 22 Apr 2008 20:03:42 +0100
- To: Michael Kifer <kifer@cs.sunysb.edu>
- CC: Sandro Hawke <sandro@w3.org>, "Public-Rif-Wg (E-mail)" <public-rif-wg@w3.org>
Michael Kifer wrote:
> What you are proposing is even worse than expanding the same
> macro differently in different contexts. Now you are saying that foo:bar
> really stands for "something-long-here", but in some contexts we are not
> allowed to use "something-long-here" instead of foo:bar.
it just says standalone curies mean something different than
curies after ^^ ... in the former case they denote an IRI, i.e. a
constant in the rif:iri symbol space and in the latter they denote
the IRI for a symbol space.
What is the problem with this?
The whole thing is not about CURIEs being a generic macro but about a
reasonable shortcut notation.
best,
Axel
>>> As I said, your proposal had a couple of holes, which Jos was trying to
>>> fix. Most of all, I do not like the fact that you are proposing that ":"
>>> would macro-expand differently depending on where it appears (after the ^^
>>> or elsewhere). My second proposal (<prefix:suffix>) was to fix that.
>> The problem with using "<" and ">" like this:
>>
>> In practice, URIs are delimited in a variety of ways, but usually
>> within double-quotes "http://example.com/", angle brackets
>> <http://example.com/>, or just by using whitespace:
>>
>> http://example.com/
>>
>> These wrappers do not form part of the URI.
>>
>> (from RFC 3986 [1]), and the various Semantic Web specs all use <...> in
>> this way, to delimit URIs. I think a good middle ground is something
>> like:
>>
>> 1. A "prefix" declaration syntax, as in Turtle:
>>
>> @prefix ns: <http://example.org/ns#> .
>>
>> or SPARQL:
>>
>> PREFIX ns: <http://example.org/ns#>
>>
>> or, maybe best, something more RIF-PS like:
>>
>> PREFIX("ns", "http://example.org/ns#").
>>
>> 2. The CURIE a:b syntax is the only syntax that can be used after
>> the "^^" operator. Eg:
>>
>> PREFIX("xs", "http://www.w3.org/2001/XMLSchema").
>> PREFIX("rif", "http://www.w3.org/2007/rif#").
>>
>> ... "10"^^xsd:integer ...
>> ... "http://purl.org/dc/terms/creator"^^rif:iri
>>
>> 3. The CURIE a:b syntax MAY also be used as a shortcut for rif:iri
>> terms, so givent his PREFIX declatation:
>>
>> PREFIX("dc", "http://purl.org/dc/terms/").
>>
>> the last term in #2 above could also be written as:
>>
>> ... dc:creator
>>
>> I think that's all we really need to make IRI handling in the
>> presentation syntax relatively comfortable and precise, no?
>>
>> -- Sandro
>>
>> (Note that it seems BLD has the wrong namespace for Dublin Core. It
>> should be either "http://purl.org/dc/elements/1.1/" or
>> "http://purl.org/dc/terms/", with the latter being in some sense
>> preferred. [2].)
>>
>> [1] http://www.ietf.org/rfc/rfc3986.txt
>> [2] http://dublincore.org/documents/dces/
>>
>
--
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, 22 April 2008 19:04:27 UTC