[xml] Questions on python-libxml2

[decker dacafe com]

Hello,

I was hoping that someone here can please answer two questions concerning
libxml2 python module use:

1. Is this snippet correct?
doc = libxml2.parseDoc(readfile(filename))
ctxt = doc.xpathNewContext()
ctxt.xpathRegisterNs("xlink","http://www.w3.org/1999/xlink";)

... if so, to what purpose does one register the namespace
(xpathRegisterNs)???
 It doesn't seem to effect the outcome of the script:
http://66.102.7.104/search?q=cache:s_SlS9Ro_yAJ:dreams.wagstrom.net:8080/weblog/2004/Jan+xlink+python&hl=en&ie=UTF-8

...so I can't understand why it is being used.


2. Why do I seem to get unpredictable behaviour from code like:
doc = libxml2.parseFile("D:\\D\\XML\\system.xml")
current_nodes = doc.xpathEval("descendant-or-self::linux")
node = current_nodes[0]
print node
ctxt = node
while node:
    node = node.xpathNextDescendant(node)
    print node

How would I generate a list of all decendants of a node (besides searching
for children of children)?


3. Is there any such thing as an xlink ELEMENT (where element.ns =
"http://www.w3.org/1999/xlink";)? The only examples that I can find only
demonstrate xlink ATTRIBUTES (where the namespace has to be declared in
every element with xlink attributes). I don't even know the reason for
declaring a namespace if we always do that.


Hopefuly someone can clear up my confusion.


Ben






-----------------------------------------
This email was sent using DACafeMail.
Get Your 10 MB eMail Account Now.
http://cafemail.mcadcafe.com