- From: <keshlam@us.ibm.com>
- Date: Thu, 8 Jun 2000 11:05:35 -0400
- To: xml-uri@w3.org
Quoth the honorable Mr. Berners-Lee: >I have also shifted ground in that rather than simply insisting on absolutizing, I can see we may have to compromise with >banning relative URIs, because the interpretations of them >are simply inconsistent. I think all of us (myself included) have finally started realizing that this is _NOT_ a trivial problem, and that all the proposed answers really have had significant costs associated with them as well as benefits. >1) Namespace references are URI-references according to the spec. >.. > The bit in the Namespace Recommendation about character-for-character >comparisons > was wrong because no one had then spotted that it provided inconsistencies >with > relative URUI references. There's a conflict there, agreed. This proposal reverses prior intent, which Tim Bray has stated was equivalent to your Option 3. I can see _why_ you want to reverse the intent; it permits the Namespace Name to become a URI with all the benefits and baggage thereof. (Which you might want to explain to folks, so we have a better idea of why this is considered important -- I know I don't understand them well.) In that scenario the namespace declaration to become a reference to that URI, with all the baggage _that_ implies. Downsides: What if there's no base URI. Are we happy with weak inequality. Do we want to spend cycles on something for which a need has not been established. >2) Namespace references are URI-references but the use of relative-URIs is > not allowed in a conforming document. The results of using one are >undefined Essentially, this is a deprecation -- while reserving the right to reintroduce relative syntax later if/when a strong case can be made for it. Leaving it undefined does provide a path for those who are already using that syntax. Folks who want to invest the cycles can absolutize, folks who don't can issue warnings/errors or treat them as literal. This minimizes the impact on existing code and documents... which may be a bad argument from a comp-sci perspective but is a very good one from a software engineering standpoint. I think this one has a real chance of getting off the ground. It's something we can agree on _NOW_, so the specs which are hanging fire can proceed. (However, I don't think one should assume that full relative-reference support will be added in XML 2.0. I think it's certainly worth further discussion, but it's going to have to justify itself under the 90/10 rule. For that reason alone, deferring it makes sense; its proponents really need time to establish a compelling family of usecases.) This solution needs a short name for further discussion. I propose "Deprecate/Undefined", or one of those two keywords. >3) Namespace names look like (have the syntax of) URI references but are not. >I could not live with that. I believe those of us who favored this Literal reading would be willing to accept Deprecate/Undefined (your #2). <grin>We may or may not resume arguing when a definition _is_ proposed in the XML 2.0 timeframe, of course, depending on what that proposal is and how well it's justified, but that's business as usual.</grin> ______________________________________ Joe Kesselman / IBM Research
Received on Thursday, 8 June 2000 11:55:15 UTC