If everybody agrees on the fact that it is better to use the LibXML library

Definitely don't use XML::Simple! Next to XML::LibXML, there are other good XML modules out there, such as XML::Twig or XML::Rules, each with strengths in certain areas, but XML::LibXML is definitely the most general-purpose. If you're not sure, use XML::LibXML.

I didn't know the "say" feature. I'll have a look at it to better understand what it does.

say is equivalent to print with a newline appended. It's available on Perl 5.10 and up when you say use 5.010; or use feature 'say'; at the top of the script.