Dear Monks,

I am navigating a nested XML data structure and at some point, I want to retrieve the value of a tag having a specific attribute. I cannot figure out why I am not getting anything from the minimal reproducible below (return 0). 

use strict;
use XML::LibXML;

my $parser = XML::LibXML->new;
my $doc = $parser->parse_file("minimal.xml");

my @vol = $doc->findnodes(q {Volume[@VolumeCategory="L"]});
# also tried various quoting scheme...
my $tmp = scalar(@vol);
print "Number of entries: $tmp \n"; # 0

[download]
minimal.xml 
<root>
<ProductKey>99</ProductKey>
<Volume VolumeCategory="L" MeasurementCategory="Real">0.063</Volume>
<Volume VolumeCategory="cuft" MeasurementCategory="Real">2.2</Volume>
</root>

[download]
Any hints would be greatly appreciated!

Update: Thanks to both Ikegami and Toolic for great pointers.
Also did some spelling edit.

Update 2: It turns out my problem was related with namespace (in my large document, not the toy example I made for this post). As alluded to in numerous other postings, XML::LibXML::XPath offered the registerNs method which then made XPath expressions find everything I needed. Thanks to all for your inputs, guidance and alternate solutions.

In reply to Finding node with attribute XML::LibXML by jjap

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