I am often having trouble remembering which Perl modules I have installed, where they are, what the paths in Perl are, etc. Yesterday I discovered a great little Perl script that does exactly what PHPinfo.php scripts do for PHP installs. It displays many variables about Perl, and best of all - all perl modules installed (including links to pages on CPAN for more info on module).
This is a no brainer install. Download the text file, change the name to perldigger.cgi, drop it in your CGI directory (/Library -> WebServer -> CGI-Executables by default), and change the file to executable (chmod 755 perldigger.cgi). Then just visit http://localhost/cgi-bin/perldigger.cgi (or similar depending on your setup).
Get the script and more info here:
http://sniptools.com/perldigger
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