Perl XML/SVG Parser unable to findnodes

Question

In the following code, I am trying to parse an SVG file and delete all text nodes in it. However, it does not work (Code never goes into the forloop for findnodes). What am I doing wrong? I tried with XPath and LibXML version of the code, but none of them worked. They parse and dump the file fine, but the findnodes matches nothing. ``` #!/usr/bin/perl use strict; use warnings; use XML::XPath; use XML::XPath::XMLParser; my $num_args=$#ARGV+1; if($num_args != 1) { print "Usage: $0 "; exit(1); } my $file=$ARGV[0]; my $doc = XML::XPath->new(filename => $file); foreach my $dead ($doc->findnodes('/svg/text')) { print "Found Text Node "; $dead->unbindNode; } ``` Starting few lines of the SVG file: ```

Accepted Answer

`/svg/text` looks for `text` elements directly under the `svg` root element. That is not what you have here. It looks like what you want is `text` elements anywhere in the document, which would be `//text`. This should work with XML::XPath.

If you want to use XML::LibXML, which you should since it is a much better module than XML::XPath (better maintained, more efficient, more powerful), then you have to pay attention to namespaces: the whole document has a default namespace (the `xmlns="http://www.w3.org/2000/svg"` bit in the opening tag). You will need to declare it and use XML::LibXML::XPathContext to evaluate the XPath expression, including the prefix.:

```
#!/usr/bin/perl

use strict;
use warnings;

use XML::LibXML;
use XML::LibXML::XPathContext;

# it's easier to test directly @ARGV in scalar context than to use $#ARGV
if(@ARGV != 1) { print "Usage: $0 <filename>
"; exit(1); }

my $file=$ARGV[0];

my $doc = XML::LibXML->load_xml( location => $file);

my $xpc = XML::LibXML::XPathContext->new( $doc);     # create the XPath evaluator
$xpc->registerNs(x => 'http://www.w3.org/2000/svg'); # declare the namespace as x

# the query now uses x as the prefix for the svg namespace
foreach my $dead ($xpc->findnodes('//x:text')) {
    print "Found Text Node
";
    $dead->unbindNode;
}
```

Perl XML/SVG Parser unable to findnodes

Solution

Problem