Re: Bugzilla issue 10, was: Plan to resolve issues in 2518bis

Thanks for the good explanation - I get it now. What a nightmare.

On 10/5/05 2:47 PM, "Julian Reschke" <julian.reschke@gmx.de> wrote:

> Cullen Jennings wrote:
>> 
>> I'm not sure I understand what you mean by namespace preservation. Take the
>> example portion of some XML:
>> 
>> <h:html xmlns:xdc="http://www.xml.com/books"
>>         xmlns:h="http://www.w3.org/HTML/1998/html4">
>>  <h:head><h:title>Book Review</h:title></h:head>
>>  <h:body>
>>   <xdc:bookreview>
>>    <xdc:title>XML: A Primer</xdc:title>
>> 
>> Is it the "http://www.xml.com/books" that gets preserved or the "xdc". What
>> I'm trying to ask is if would be OK if the above XML got transformed to
>> 
>> <h:html xmlns:foo-xdc="http://www.xml.com/books"
>>         xmlns:h="http://www.w3.org/HTML/1998/html4">
>>  <h:head><h:title>Book Review</h:title></h:head>
>>  <h:body>
>>   <foo-xdc:bookreview>
>>    <foo-xdc:title>XML: A Primer</xdc:title>
>> 
>> I suspect you are saying this is not OK and the namespace prefix (ie the
>> xdc) needs to be preserved and not changed to foo-xdc. If this is
> what you
>> mean, then I am not sure what you mean by this is important for XSLT
> and XML
>> Schema, can you provide a bit more of an example.
>> 
> 
> The namespace URI definitively needs to preserved, I don't think there's
> any question about that.
> 
> What this issue is about is whether if it's a problem to get
> 
> <xyz:title xmlns:xyz="http://www.xml.com/books">XML: A Primer</xyz:title>
> 
> or
> 
> <title xmlns="http://www.xml.com/books">XML: A Primer</title>
> 
> instead.
> 
> *Usually* that doesn't make a difference, and in a perfect world, it
> never would. Unfortunately, this isn't a perfect world and a long time
> ago, XML vocabularies have started to leak prefixes into text content
> and attribute values.
> 
> Consider:
> 
> <xsl:template match="D:propfind" xmlns:D="DAV:">
> 
> In this case, loosing the "D" prefix actually breaks the semantics of
> the document, such as in:
> 
> <xsl:template match="D:propfind" xmlns:ns0="DAV:">
> 
> This is an example from XSLT/XPath, similar cases can be constructed
> with documents that use XML Schema, such as in
> 
> <count xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
>     xmlns:xs="http://www.w3.org/2001/XMLSchema"
> xsi:type="xs:integer">123</count>
> 
> For the record, the XML Infoset spec includes prefixes.
> 
> So no, rewriting namespace prefixes is *not* without problems, and
> *will* break semantics of XML content. Thus, we should either require
> prefixes to be preserved, or at least state that this part of the XML
> Infoset may not round-trip through WebDAV properties.
> 
>> Thanks for educating me on this - I'm not really going to end up with much
>> of an opinion on any of this but I am making sure I know enough to at least
>> understand the argument. Also, I suspect I might not be the only one of the
>> list that does not understand as much about XML as I wish I did :-)
> 
> Sure :-)
> 
> Best regards, Julian

Received on Friday, 7 October 2005 04:28:21 UTC