Re: [xml] make XPointer( id(XX) ) and C14n work without DTD

[Andrew Fan <Andrew Fan Sun Com>]

Hi Daniel,

I have make it work with a XPath, "<XPath>/test/content</XPath>". But I 
worried about the performance if the file is big enough, such as 20M. I 
think XPointer( id() ) have a good performance anyway. Would you please 
give me some suggestion about how to improve performance of XPath?

Thanks & Regards,
Andrew

Daniel Veillard wrote:

> On Tue, Feb 24, 2004 at 11:28:46AM +0800, Andrew Fan wrote:
>  
>
> > Daniel Veillard wrote:
> >
> >    
> >
> > > On Mon, Feb 23, 2004 at 06:29:23PM +0800, Andrew Fan wrote:
> > >
> > >
> > >      
> > >
> > > > Hi,
> > > >
> > > > I have a xml file like,
> > > > ---------
> > > > <test>
> > > > <content Id="target">
> > > > Hello, World!
> > > > </content>
> > > > ...............
> > > > <Reference URI="#target">
> > > > </Reference>
> > > > </test>
> > > > -------------
> > > >
> > > > And I parsed it as DOM tree and want to use XPointer( id( "target" ) ) 
> > > > to get the content. Because of the absence of DTD, I have to hack the 
> > > > DOM with "xmlAddID", which make the XPointer work.  And then, I want to 
> > > > make a C14n transform over the DOM, I can not get the correct result. 
> > > > What alse must I do in order to get the correct C14n?
> > > >  
> > > >
> > > >        
> > > XPointer id() is actually XPath id() and only works if you can assert
> > > IDness of an attribute, and that requires a DTD per the spec. Trying to
> > > make what you suggest would simply make the library not conformant to the
> > > specifications. Sorry that's not possible. Use a different XPointer
> > > expression not based on id().
> > >
> > >
> > >
> > >      
> > Which XPointer expression can I used to express the above URI?  Thanks.
> >    
>
>  something like 
>     /test/content[ Id='target']
> or  //content[ Id='target']
> or  //*[ Id='target']
>
> depending on your language target which I have no idea for. You can
> find XPath tutorials all over the web,
>
> Daniel
>
>