Re: [xml-dev] Backward and forward compatible schemas ... Relax NG -->

["Anthony B. Coates (XML-Dev)" <abcoatesecure-xmldev@yahoo.co.uk>]

I agree with Dave here.  It's not in the best interests of fair play to  
make a blanket statement about W3C XML Schema based on what is, to be  
honest, something of an edge case.  In practice, people regularly create  
suitably backwards and forwards compatible Schemas using W3C XML Schema,  
and that reality shouldn't be overlooked.

Cheers, Tony.

On Fri, 24 Aug 2007 06:33:27 +0100, Dave Orchard  
<orchard@pacificspirit.com> wrote:

> The blanket statement that XML schema 1.0 does not support forwards and  
> backwards compatibility is incorrect.  Using an "Extension"
> or "Sentinel" element, one can get around XSD 1.0 UPA constraints at the  
> cost of extra markup in instances.  This is shown in the
> W3C TAG Versioning Finding(editors draft) XML and Schema doc, section  
> 7.4 http://www.w3.org/2001/tag/doc/versioning-xml#versionid3
> and in the section 4 "Version Strategy" of an XML.com article explaining  
> forwards compatibility using XSD 1.0
> (http://www.xml.com/pub/a/2004/10/27/extend.html?page=4)
>
> Cheers,
> Dave

-- 
Anthony B. Coates
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Miley Watts LLP
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