xml-dev - Re: ubiquitous XML?

[Rick JELLIFFE <ricko@geotempo.com>]

"Bullard, Claude L (Len)" wrote:
> 
> And I repeat, to replace them with what given
> that they are still a fundamental formal definitional
> tool for XML itself?

Path=based assertion languages such as Schematron or Xlinkit are just as
susceptible to formal definitions as DTDs are, especially if we take
"extensibility" seriously and start from open content models.  One of
the deficiencies of grammar-based systems, for example, is that they do
not provide enough information to let you know which elements can be
used in external vocabularies and which are compound (i.e. which have
upward-going cohesion).  

All schema languages are partial. Some are more difficult than others,
and this difficulty can hit some cultures or technical specializations
more than others. I am interested to know if formal grammars are taught
as a standard part of US MIS courses (not computer science courses).  

Cheers
Rick Jelliffe