Re: [xml-dev] SGML default attributes.

["Liam R. E. Quin" <liam@w3.org>]

On Fri, 2016-05-06 at 12:47 +1000, Rick Jelliffe wrote:
> 
[...]
> Also on Eliots point that dtds etc have limitations in their power: 

All formal systems, of course, are limited, whether by the Arch of
Compassion or by the mathematical inevitability of completeness :-)

> one
> limitation is how to capture (without resorting to ad hoc comments)
> some constraints that are beyond the expressive power of the grammar
> or are contingent in some way.  I believe Schematron is still the
> only system to take this seriously.
To some extent XSD does too, by allowing embedded Schematron rules :-)
or other extension mechanisms. DTDs do too, using processing
instructions, although it's terribly underspecified.

Best,

Liam


-- 
Liam R. E. Quin <liam@w3.org>
The World Wide Web Consortium (W3C)