[XML-SIG] [XML-checkins]Evaluate on nodes

[Jeremy Kloth]

On Wednesday 11 January 2006 16:10, Vladimir Blagojevic wrote:
> Hi,
>
> I am new to PyXml and I am struggling with xpath evaluation. Namely,
> if I pass a node to the Evaluate function instead of the whole
> document, I would expect the xpath evaluation to start from that node,
> not from its containing document.
>
> Let me illustrate my problem with an example:
>
> doc =
> minidom.parseString('<table><tr><td><table><tr/></table></td></tr><tr/></ta
>ble>') print len(xpath.Evaluate('//tr', doc.documentElement))
> 3
> td = xpath.Evaluate('//td', doc.documentElement)[0]
> print len(xpath.Evaluate('//tr', td))
> 3
>
> I would expect 1, since the td element only contains onew descendant
> tr element.
>
> If one looks at the code of ParsedAbbreviatedAbsoluteLocationPath.py,
> we see why:
>
> root = context.node.ownerDocument or context.node
>
> I would expect this to read:
>
> root = context.node or context.node.ownerDocument

If you change your expression to read ".//tr", an 
AbbreviatedRelativeLocationPath, you should get the result you are expecting.
-- 
Jeremy Kloth
http://fourthought.com/
http://4suite.org/