Re: Why not XHTML+RDF? was Re: Links are links

Jonathan Borden wrote:
> Paul Prescod wrote:
> 
> 
>>In *my* markup language it is my perogative to weigh the costs and
>>benefits of elements vs. attributes for myself. My choice should not be
>>constrained by XLink or RDF M&S.
>>
> 
> 
> Certainly, and *your* applications will perfectly understand the semantics
> of *your* markup language. 

I want my cake and to eat it to and you haven't offered a technical 
reason why this is impossible. Dare I mention the H-word. HyTime 
demonstrated that it is possible to turn any attribute into a locator 
for any other element and to infer locator roles and link types from 
element types and attribute names. It used a syntax that was hideous for 
the language designer but invisible for the language user. The attribute 
was 100% owned by the language designer in terms of name and even to a 
certain extent internal syntax. And it was 100% understandable by any 
Hytime engine (which is to say, either of them). And that was in 
1992-1996 without benefit(?) of any of our modern conveniences like 
namespaces, XPath, the DOM, schemas, etc.

> ... I'm not sure that I want to bother figuring all
> this out, nothing personal, and particularly for standard languages, I'd
> very much like to use standard mechanisms, standard software modules, etc.

Who said anything against standard mechanisms and standard software modules?

>...
> Sort of like how most folks have decided to code in high level languages
> rather than machine code. Frequently it is possible to improve performance,
> decrease memory footprint etc, by hand optimizing machine code, but at what
> cost? I had thought that the general idea of using XML was to allow
> application programmers to focus on semantics as encoded in software, rather
> than syntactic issues, parsers etc. etc. 

You are half right. XML allows you to avoid thinking about lexing. But 
an XML schema is designed to declare a syntax and in fact is just a 
glorified, er, syntax, for a grammar-definition language.

XML caught on because it allowed people to define their own syntaxes 
quickly and easily.

> ... Generally it is possible to take
> _any_ XML language and further optimize it (perhaps in terms of
> characters/document etc.) by rewriting it in SGML e.g. using tag
> minimization etc. or s-expressions, or whatever other custom syntax... but I
> thought we were trying to get -beyond- such arguments (e.g. parens vs. angle
> brakets)

The cost/benefit ratio in giving up control of parens vs. angle backets 
is huge (because there is NO algorithm for parsing arbitrary languages 
in constant time from simple-to-read grammars). But the cost/benefit 
ratio for XLink and RDF is much smaller. I can easily invent an 
algorithm to convert from arbitrary XML to RDF or XLink in constant time 
based on a declarative specification. I had a way of doing more or less 
that years ago.

  Paul Prescod

Received on Wednesday, 2 October 2002 18:35:10 UTC