On Tue, Nov 26, 2013 at 2:38 AM, Stefan Behnel <stefan...@behnel.de> wrote: > larry.martell...@gmail.com, 25.11.2013 23:22: >> I have an XML file that has an element called "Node". These can be nested to >> any depth and the depth of the nesting is not known to me. I need to parse >> the file and preserve the nesting. For exmaple, if the XML file had: >> >> <Node Name="A"> >> <Node Name="B"> >> <Node Name="C"> >> <Node Name="D"> >> <Node Name="E"> >> >> When I'm parsing Node "E" I need to know I'm in A/B/C/D/E. Problem is I >> don't know how deep this can be. This is the code I have so far: >> >> nodes = [] >> >> def parseChild(c): >> if c.tag == 'Node': >> if 'Name' in c.attrib: >> nodes.append(c.attrib['Name']) >> for c1 in c: >> parseChild(c1) >> else: >> for node in nodes: >> print node, >> print c.tag >> >> for parent in tree.getiterator(): >> for child in parent: >> for x in child: >> parseChild(x) > > This seems hugely redundant. tree.getiterator() already returns a recursive > iterable, and then, for each nodes in your document, you are running > recursively over its entire subtree. Meaning that you'll visit each node as > many times as its depth in the tree. > > >> My problem is that I don't know when I'm done with a node and I should >> remove a level of nesting. I would think this is a fairly common >> situation, but I could not find any examples of parsing a file like >> this. Perhaps I'm going about it completely wrong. > > Your recursive traversal function tells you when you're done. If you drop > the getiterator() bit, reaching the end of parseChild() means that you're > done with the element and start backing up. So you can simply pass down a > list of element names that you append() at the beginning of the function > and pop() at the end, i.e. a stack. That list will then always give you the > current path from the root node.
Thanks for the reply. How can I remove getiterator()? Then I won't be traversing the nodes of the tree. I can't iterate over tree. I am also unclear on where to do the pop(). I tried putting it just after the recursive call to parseChild() and I tried putting as the very last statement in parseChild() - neither one gave the desired result. Can you show me in code what you mean? Thanks! -larry > > Alternatively, if you want to use lxml.etree instead of ElementTree, you > can use it's iterwalk() function, which gives you the same thing but > without recursion, as a plain iterator. > > http://lxml.de/parsing.html#iterparse-and-iterwalk -- https://mail.python.org/mailman/listinfo/python-list
