I want to use XML::LibXML to process OpenOffice (sxw) files. OpenOffice stores its information in a Zip archive containing several XML files. I have extracted the content.xml file from such an archive.

I have used XML::LibXML before, but never with XML documents that use namespaces. OpenOffice files use various namespaces for the different types of content.

Normally, I would write something like: 

my $parser = XML::LibXML->new() or die $!;
my $tree = $parser->parse_file('content.xml') or die $!;
my @nodes = $tree->findnodes('//p');

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to retrieve all the nodes of type p. OpenOffice stores paragraphs in p elements within the text namespace. So, I replaced the findnodes line above with: 
my @nodes = $tree->findnodes('//text:p');

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but this returns the error XPath error Undefined namespace prefix in //text:p xmlXPathCompiledEval: evaluation failed.

I fixed this problem with: 

my @nodes = $tree->documentElement->findnodes('//text:p');

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but I don't understand why one way works and the other way doesn't. Both contexts (tree and documentElement) work with another XML document that does not use namespaces.

Can anyone here enlighten me?

In reply to XML::LibXML and XML Namespaces (processing OpenOffice documents) by tomhukins

Title:
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