W3C home > Mailing lists > Public > www-tag@w3.org > February 2006

Re: Principle of Least Power (was Re: Agenda of 7 February 2006 T AG teleconference)

From: Dan Connolly <connolly@w3.org>
Date: Wed, 08 Feb 2006 08:30:06 -0600
To: Elliotte Harold <elharo@metalab.unc.edu>
Cc: "Bullard, Claude L (Len)" <len.bullard@intergraph.com>, "'Henry S. Thompson'" <ht@inf.ed.ac.uk>, noah_mendelsohn@us.ibm.com, Vincent.Quint@inrialpes.fr, www-tag@w3.org
Message-Id: <1139409006.12577.171.camel@dirk.w3.org> 

On Wed, 2006-02-08 at 08:04 -0500, Elliotte Harold wrote:
> Dan Connolly wrote:
> 
> > Schematron is turing-complete, as I understand. DTDs are not.
> 
> 
> Schematron is not Turing complete. It has no loops or recursion. 

Ah. Thanks for correcting my misimpression.

> remember it is based on XPath (not Turing complete) rather than XSLT 
> (Turing complete). It is often implemented in XSLT, but it does not 
> provide full access to XSLT from the Schematron language itself.

I suspect it's still more expressive than DTDs, though I'm not certain.
Surely the XPath string and numeric operations are more expressive
than DTDs. Seems like an interesting research topic.

-- 
Dan Connolly, W3C http://www.w3.org/People/Connolly/
D3C2 887B 0F92 6005 C541  0875 0F91 96DE 6E52 C29E
Received on Wednesday, 8 February 2006 14:30:27 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Thursday, 20 September 2007 13:53:04 GMT