Re: suggest validator prefer URI to FPI

On Wed, 2004-08-04 at 11:27, Terje Bless wrote:
> Hash: SHA1
> Dan Connolly <> wrote:
> >In the validator catalog [] we have
> >
> >PUBLIC  "-//W3C//DTD XHTML 1.0 Strict//EN"
> >        "REC-xhtml1-20020801/xhtml1-strict.dtd" []
> >
> >I suggest adding entries that key on the URI before those entries,
> To what purpose?

I answered that elsewhere in my message, though evidently
not in a way that persuaded you.

> >The validator seems to recognize the given FPI and ignore the URI:
> The Markup Validator will prefer the PUBLIC Identifier to any SYSTEM
> Identifier, yes.

I'm suggesting that's a bug.

> >I expected it to check the document agains the transitional DTD;
> Then your expectation was clearly unwarranted.
> >that is, I expect it to use the URI that was provided, since FPIs don't
> >give the same network effects
> I'm quite certain I disagree with the argument put forth there and in the
> referenced document, but in any case I think any postulated relevance of
> economic theories applied to technology are entirely irrelevant to the issue
> at hand.

The validator is an important outreach mechanism; it's one way that
a lot of people get exposed to principles of Web Architecture in
a tangible way. Hence the arguments in the Web Architecture document
are not irrelevant; it's important that the markup validation service
exhibit the principles of Web Architecture.

I'm interested to know if others find the arguments in
persuasive or not; i.e. whether they agree with me that
the markup validation service should prefer URIs to FPIs.

> >Hmm... I wonder if it's wise to override relative URIs with entries
> >like...
> >
> >SYSTEM "spec.dtd" ""
> No, probably not.

OK; I hope it'll get removed soon (provided others concur with us).
I'm happy to remove it if you prefer.

>  It was however necessary in order to prosess the "spec-prod"
> XML versions of W3C Recommendations as these typically (at the time that entry
> was added) did not choose to make use of a PUBLIC Identfier and included a
> relative SYSTEM Identfier referencing a location that did not exist.

The early versions of the XML Recommendation are not valid XML
documents; the markup validation service should not say that they are;
it should not mask bugs.

> Hmmm. Is this the "Network Effect" you were thinking of?

In a way, yes: the same link checking techniques that work for
<a href="...">...</a> can and should be applied to references
from documents to external subsets; the bug in the early
XML recommendations could have been caught earlier. But people
were using on another system of identification, FPIs, and so
did not benefit from the existing URI infrastructure; they
didn't get the network effect benefits.

>  That noisome negative
> part of the whole "network effect" hype that so many dotcoms failed to take
> into account?

I don't understand what you mean by that.

>  If that's the case, then sure, prefering a SYSTEM identfier to a
> PUBLIC identfier does have several negative effects such as the above.
> This is clearly a widespread problem judging by the W3C Recommendatations that
> encourage authors to reference a DTD with a relative SYSTEM identifier in
> documents not destined for publication in the URL space.

I agree, the use of broken relative SYSTEM identifiers is a problem;
I'd like the markup validation service to provide clear feedback
about that problem.

> Thanks for your feedback on this.


Dan Connolly, W3C

Received on Wednesday, 4 August 2004 13:08:38 UTC