Re: [xml] Question regarding Xpath and streaming

[Daniel Veillard <veillard redhat com>]

On Mon, Jun 25, 2007 at 06:24:46PM -0700, Yong Chen (yongche) wrote:
> 
> Hi,
> 
> I've a question regarding xpath and streaming (xmlWriter):
> 
> I use xpath to filter a document so I get selected (or filtered) nodes.
> I also use xmlWriter to stream output. I wonder if I can use both
> together.
> 
> Libxml xpath works by first getting xmlXpathContextPtr (API:
> xmlXpathNewContext(doc)), this means the document (doc) has to be
> available. But if I'm streaming the data into a file
> (xmlNewTextWriterFilename()), I don't have the doc available. So how can
> I apply the xpath filtering in xmlWriter streaming?

  Normal XPath operations require a full tree.
  There is a pattern module allowing to stream for a very small subset of
XPath, see http://xmlsoft.org/html/libxml-pattern.html , but I don't have
user friendly docs for it.

Daniel

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