The one element schema language (was Re: Are we losing out because ofgrammars?)

[Rick Jelliffe <ricko@allette.com.au>]

From: Charles Reitzel <creitzel@mediaone.net>

 >"document z must have a element y" is *not* a basic requirement.  The
simple
>reason why is processing cost.  Schema designers (users of schema
languages)
>need predictable behavior from schema validation.  It is downright easy to
>implement such checks at the application level, especially after the schema
>checks out.

Ah. You have an idea of an application level distinct from the schema
processing.

>Also, we needed the simple stuff over a year ago.  I think the world is
>tired of waiting for basic schema features until every last fine detail of
>complex cases to be worked out.  It's getting silly and costing everyone
>time, money and hair.  It was fine for committees haggle for years over
C++,
>as long as we had C to work with in the mean time.

The work on Schematron, TREX and RELAX has not held up XML Schemas at all.
On the contrary, the more knowledge of schema issues and techniques, the
better comments people give: James and Murata-san have given some of the
most insightful comments on XML Schemas.

And just to be (constructively) bolshie about it, I have come up with a new
schema language "Hook" based on a new paradigm "partial ordering" which only
uses one element.  See http://www.ascc.net/xml/hook  for the idea.

Cheers
Rick