I tried to check if XML::Simple is installed in my system or not.
perl -e \'while (<@INC>) { while (<$_/*.pm>) { print \"$_\\n\"; } }\' >
perl -e \'while (<@INC>) { while (<$_/*.pm>) { print \"$_\\n\"; } }\'
If you're running ActivePerl under Windows:
C:\>ppm query * to get a list of all installed modules
C:\>ppm query *
C:\>ppm query XML-Simple to check if XML::Simple is installed
C:\>ppm query XML-Simple
XML::Simple