Help debugging xpath in Perl

tweetiepooh has asked for the wisdom of the Perl Monks concerning the following question:

Greetings Perl Monkers

I've been parsing some XML files using Perl and XML::Twig. I've got the bulk working but I need to parse a final, separate file just extracting out one bit of data. I can to it with xmllint on the command line using - xmllint --format portletEntities.xml --xpath '//*[@name="FilterName"]/*/text()' | sort | uniq

I'd like to get this to work in the Perl code so the values I pull from this search with the other data, in the example below I want "Name_of_filter". Using xmllint with //*[@name="FilterName"]the surrounding data looks like

<portletentities:adminPrefs name="FilterName" readOnly="false"><portletentities:value>Name_of_filter</portletentities:value></portletentities:adminPrefs>

There 72 entries in raw, 56 unique. In Perl I'm trying this

130 sub parsepages {
131     my $filename = "portlentEntities.xml";
132 
133     my $p = XML::Twig->new(
134     twig_handlers => {
135         '//*[@name="FilterName"]/*/text()' => sub {$_->print}
136         },
137     );
138 
139     $p->parsefile($filename);
140 }
[download]

Leads to this

unrecognized expression in handler: '//*[@name="FilterName"]/*/text()' at ./xmlp.pl line 137.

Comment on Help debugging xpath in Perl Select or Download Code

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Re: Help debugging xpath in Perl by choroba (Cardinal) on Mar 12, 2021 at 19:27 UTC
It seems XML::Twig doesn't understand `/text()`. But maybe you don't need it? This seems to work: `'//[@name="FilterName"]/' => sub {print $_->text}` [download] If you want to use the full XPath, switch to XML::LibXML. For large files, you can use its XML::LibXML::Reader. To experiment with XPath, you can use XML::XSH2, which is like xmllint combined with Perl. `map{substr$_->[0],$_->[1]\|\|0,1}[\\|\|{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^ARGV,3]`	[reply] [d/l] [select]
Re^2: Help debugging xpath in Perl by tweetiepooh (Hermit) on Mar 17, 2021 at 09:34 UTC
Super, that cracked it. Many thanks. Now to pull all the little bits of data together.	[reply]


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