Tim, greetings.
On 2012 Mar 25, at 17:35, Tim Berners-Lee wrote:
> (Not useful to talk about NIRs. The web architecture does not. Now does
> Jonathan's baseline, not HTTP Range-14. Never assume that what an IR is
> about is not itself a IR.)
Well, httpRange-14 sort of does talk about 'non-information resources', by
necessary implication. If the set of information resources (IR) is not the
same as the set of all resources (R), then the set R\IR (which in any case
exists) is non-null, and might as well be called the set of
'non-information-resources' as anything else. But perhaps R\IR is a better
notation. (I don't intend this to be hair-splitting)
Parenthetically, what _is_ IR? Referring to Rees's editors draft [1],
[issue-14-resolved] effectively says that iff a resource X is 200-retrieved,
then it must _always_ be assigned to the set IR (the resolution seems to
effectively define 'being 200-retrievable' as the definition of 'information
resource', and this is consistent with [1] section 1.1 which says "One
convention[...] was for a hashless URI to refer to the document-like entity
("information resource") served at that URI").
So my phrasing was intended to weaken [issue-14-resolved] to suggest that X
being 200-retrievable puts X in IR, _only_ if the documentation about X
(retrieved by conneg on X, say) does not put it in R\IR.
How something is put into R\IR is a separate issue. Perhaps there's a need for
a class std:RnotIR, or perhaps this is up to the client, who may decide that
discovering that 'X a foaf:Person' is enough to put it in R\IR for the client's
purposes.
----
Example:
So, if X=http://example.org/cedric 200-returns
<> foaf:name "Cedric".
then X is in IR, and oddly enough has a name (the domain of foaf:name isn't
restricted to foaf:Person). If it 200-returns
<> foaf:name "Cedric";
a foaf:Person.
then the client should deem X to be in R\IR.
----
This does mean that the RDF description document which has been retrieved from
the URI X doesn't have a name at this point. But if that matters to the owner
of X (perhaps because they want to refer to how the description document is
licensed), then this minority (?) situation can be managed by having retrieval
of X produce
<> a foaf:Person;
eg:describedBy <http://example.org/cedric-description>.
<http://example.org/cedric-description> eg:licensed <cc-by>.
That places X in R\IR, and indicates a description document about which
anything one wishes can be asserted.
All the best,
Norman
[1] http://www.w3.org/2001/tag/doc/uddp-20120229/
--
Norman Gray : http://nxg.me.uk
SUPA School of Physics and Astronomy, University of Glasgow, UK
