- From: Dan Connolly <connolly@w3.org>
- Date: Thu, 18 Sep 2008 11:35:25 -0500
- To: www-tag <www-tag@w3.org>
I don't see how to make sense of this
"MUST NOT resolve directly to a representation"
in
http://wiki.oasis-open.org/xri/AbstractIdentifierArchitecture
last edited 2008-09-04 01:42:20
Consider:
a1 resolves to d1
d1 contains c2
c2 resolves to r2
So a1 is abstract, right?
But then I can make another resolution mechanism
by composing the original "resolves to"
with extracting concrete identifiers from
descriptions and resolving them:
def resolves2(ident):
try:
r = resolve(ident)
return r
except OnlyDescriptionAvailable, d:
for c in d.concrete_identifiers():
try:
r = resolve2(c)
if r: return r
except:
pass
now resolves2(a) = r2. So I guess a
isn't abstract after all.
Perhaps it would make sense to define
abstractness _with respect to a given resolution mechanism_ a la:
Identifier I for resource X is abstract with respect
to resolution mechanism L there
is no representation R of X where L resolves A to R.
All this is to say: whether an identifier is abstract
or not is not a property of the identifier itself.
Is info:abcdef abstract? Well, maybe today, but if
the connection between that sort of identifier and
representations of the resources they refer to
is sufficiently valuable, someone will deploy a
new resolution service, and suddenly info:abcdef
is no longer abstract.
--
Dan Connolly, W3C http://www.w3.org/People/Connolly/
gpg D3C2 887B 0F92 6005 C541 0875 0F91 96DE 6E52 C29E
Received on Thursday, 18 September 2008 16:35:36 UTC