Code::Perl allows you to build chunks of Perl code as a tree and then when you're finished building, the tree can output the Perl code. This is useful if you have built your own mini-language and you want to generate Perl from it. Rather than generating the Perl at parse time and having to worry about quoting, escaping, parentheses etc, you can just build a tree using Code::Perl and then dump out the correct Perl at the end.