Re: XHTML Working Draft--URLs for system ids of char entity decls

Paul Grosso <pgrosso@arbortext.com> writes:
> 
> Murray,
> 
> Thanks for the reply.  I don't want to rehash the WG's discussions,
> but I can't help but make some comments embedded below.

No, I don't want you to think that I'm not open to suggestion. As you
might have gathered, this seems like a pretty shaky decision to me, too.

> At 15:52 1999 03 22 -0800, Murray Altheim wrote:
> 
> >This was discussed at some length, and the decision to not use absolute
> >URIs was made for two reasons:
> >
> >   1. Because the XML Recommendation does not specify whether the 
> >      publicId or systemId has precedence, there was concern that
> >      if XHTML authors were to simply use the URL as provided (which
> >      I believe the vast majority would do), there may be an 
> >      unnecessary and draining load on the W3C http server each 
> >      time an XHTML document is validated. This may be considered
> >      a more fragile situation than providing a relative URL.
> 
> I don't think these are good reasons.  The XML spec doesn't specify
> a precedence precisely because the processor should be allowed to do
> what makes sense for it.  Assuming, then, that a processor handed both
> a public id and a system id would necessarily do something stupid is
> not a good reason for anything.

I'm just not convinced that there's any wisdom in implementation on
the web, either, and perhaps the WG will decide to use the absolute
URLs. Two bad decisions don't make a right, obviously, but I think
the W3C needs to figure out if it wants to get into the DTD registry
business before this WG comes to a final decision on this topic. If
you'll note, the instances of DTDs as separate files apart from their
specifications is either rare or nonexistent within the W3C, at least
as far as I've seen.

> What could possibly be the role of the public id if it were an
> error to do anything but use the system id?

To be perfectly frank, I believe there are many who just wish that
publicIds would go away, among them I'm guessing TimBL, based on
his 'The Myth of Names and Addresses' document*, which I find rather
flawed. 

> >I believe it better to advocate that authors and others keep a 
> >copy of the DTD in the same directory as the document, and if
> >they wish to put it in a different directory in their environment,
> >that they modify their DOCTYPE's URIs to point to that new location.
> >Or use a catalog file (which is what I'd recommend if XML had them
> >in the spec).
> 
> I believe it is both bad practice and folly to assume that the DTD
> and all its referenced entities will follow the document around the web.

That's not the assumption. I am guessing that there will be wide variety
of copies of the DTD around the Web, and that organizations may begin
creating a local space for DTDs, registries are becoming available, etc.
This is one of the reasons why I think a relative URL may be better: it
points out that everyone shouldn't point to the same place. That to me
has always been the cornerstone of the Internet, distributed access.

> I agree that the use of a catalog is a good idea--in fact, that is what
> started my looking into this.  I use the catalog to map the public id
> into my local copy, but I want to know that the system id will be
> resolvable when I send out a document to someone else on the web.
> Am I confused, or isn't this the whole point of XML on the web?

Yes, but that is my point as well. If everyone receiving a document 
tries hitting the same page, requiring the W3C server to deliver the
entire DTD each time a new user accesses a document, that seems poor
design as well. Wouldn't it be better to see access to the DTD 
distributed around? That pointing everyone to the same place isn't 
a good idea? And especially if W3C isn't willing to become a DTD
registry. Now if the horsepower of a server was committed to this
I could easily agree, but not until there was some indication from
W3C that they were willing to take on this role. 

> But why make masses of individual, potentially naive, users 
> explicitly download a bunch of entities files to their local machine 
> and have to put them in a particular directory just to be able to 
> open a document in their browser?  You can't be suggesting this.  
> I must be missing something.

No, I'm simply saying that unless W3C commits sufficient resources to
supporting distribution of its DTDs en masse, I think we should take
the safer route. To me, it's a policy decision for W3C, and one that
warrants further discussion both within and above the WG level.

It's not that I don't understand your points. We have our 
teleconferences on Wednesday mornings, and I'll be sure to bring 
this up for discussion. 

Murray

* http://www.w3.org/DesignIssues/NameMyth.html
...........................................................................
Murray Altheim, SGML Grease Monkey         <mailto:altheim&#64;eng.sun.com>
Member of Technical Staff, Tools Development & Support
Sun Microsystems, 901 San Antonio Rd., UMPK17-102, Palo Alto, CA 94303-4900

              An SGML declaration does not an i18n make.

Received on Monday, 22 March 1999 19:49:03 UTC