[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
RE: Rules & Grammars
- From: "Bullard, Claude L (Len)" <clbullar@ingr.com>
- To: John Cowan <jcowan@reutershealth.com>, XML Developers List <xml-dev@xml.org>
- Date: Wed, 07 Feb 2001 09:25:32 -0600
Opinion:
1. Hard to keep context. An element:element just
overloads the human's ability to stack names. That
is, high potential ambiguity when learning how.
2. Feature rich - it takes awhile to figure out the
why of complex types, simple types, refs, then abstract
types, datatypes, and so on. Until one knows how,
the tradeoffs are enormous to manage.
3. Preconditioning - spend a long time acquiring
skills, for some, DTDs, for others relational views,
for others object classes. The XML Schema attempts
to bridge all of these with a slight leaning toward
relational views and a definite grounding in DTD
design. Confusing. You still need all the other
bits to apply schemas and they don't work the
same way in all implementations (Grimaldi's dilemma).
On the other hand, schemas are effective and expressive
if baroque. Combined with the rules languages, they are
powerful and reasonably complete. Now: what are
they powerful and complete for? The mission?
It seems to me the toughest job is mastering all
of these, tossing in RDDL, and *selling* this as
the basis for an interoperable system particularly
if the requirements for applying them are fuzzy.
And will we really try to share these across
agencies? CALS tried that. Very hard sell.
OTOH, the consulting and engineering
services aspects of enterprise design are very
lucrative, and it isn't a con. The problem
is as tough to do as the tools are to learn.
That's why they call professionals. HTML
was easy; how toStartAChat. XML++ is hard;
how to design a negotiation.
Failure to deliver the schemas can't be seen
as a reason for an economy faltering any
more than getting new grease causes a car
to lose an ungreased wheel at high speed.
The problem is mechanics and drivers that
start the race before the lube. We can't
be blamed for that, but it is our job to
deliver the grease we promised BEFORE
the race.
Len
http://www.mp3.com/LenBullard
Ekam sat.h, Vipraah bahudhaa vadanti.
Daamyata. Datta. Dayadhvam.h
-----Original Message-----
From: John Cowan [mailto:jcowan@reutershealth.com]
XML Schema, OTOH: why *that* is so hard that I fear I'm unable.
If you pile rule-based stuff onto the already overreaching
Tower of Babel, you might well get a pile of rubble.