Re: Relationship Taxonomy Questions
Murray Altheim wrote:
> Len Bullard <firstname.lastname@example.org> writes:
> >And one not embraced by the majority of web applications. They
> >may know something.
> I believe a more accurate answer here is that the majority of Web
> applications only lex the documents, and therefore don't build parse trees
> that would enable more complex link relationships.
I accept that as a fundamental. The question is why not and since
Spyglass was the company responsible for Enhanced Mosaic, you should
be able to tell me. On the other hand, ActiveCGM objects have an
application layer which they use. VRML has a very powerful link
type and script nodes with parameters.
Only the SGML community believes it can do without these things and
software, and so far, it has blown away a decade long lead
trying to do so. Fundamentally, the SGML community has
talked much and built little with regards to WAN-capable
hypermedia. I believe the inability to come to grips with
the flaw in data-declaration-only specifications is part
of the reason for that. Perhaps that is why in DSSSL there
is little of SGML and a lot of Lisp.
> This design decision may
> have been the result of the assumption of broken HTML markup and/or the
> inability of the programmers to create something as complex as nsgmls for
> WWW that could also provide error recovery. A whole lotta error recovery.
That is good. Historically, Marc Andreesen is also on record as
saying, and his company saying, "we don't believe in SGML". Berners-Lee
is on record as saying he didn't believe people would type in all
those tags, and I believe, the original model target was RTF.
That said, it is irrelevant. I think we all agree that XML will
not be targeted to the HTML user. The problem is in defining
the requirements of the user it is targeted at, and getting
those requirements written in a clear language that can be
used as a basis for implementation.
> Spyglass, Microsoft, Netscape and I'm sure most other Web browsers couldn't
> respond to a request to jump "within element with ID 'a25', to third child
> of type 'P' within the second child of type 'LI'" if you held a sharpened
> potato to their heads. And this ability is precisely (for me) one of the
> exciting promises of XML links.
Yes. On the other hand, getting a server to generate that for you
isn't difficult, so they tell us in their literature. It's done
by a process, of course.
My point is simple: no normative linktypes. A way to express a
linktype is already available. It is an element type. Will these
interoperate? Only if the application programmer understands
the behavior implied or noted. But those are application conventions
and do not belong in the normative parts of the XML specification.
If they are there, and they are not procedurally defined (that is,
the operations for the data structure are not defined by function
or axiomatically), then their originators deserve the good horse laugh
the implementors will give them, and return to writing server-side
scripts for LiveWire.