- From: Sandro Hawke <sandro@w3.org>
- Date: Tue, 22 Apr 2008 13:56:11 -0400
- To: kifer@cs.sunysb.edu (Michael Kifer)
- Cc: Axel Polleres <axel.polleres@deri.org>, "Public-Rif-Wg (E-mail)" <public-rif-wg@w3.org>
> 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/
Received on Tuesday, 22 April 2008 17:57:47 UTC