jspart is right. This has nothing to do with the question. Here's the actual quote from ActiveState (emphasis mine):

Getting your code working with PerlEx Probably the most important thing to remember when rewriting code to work with PerlEx is data persistence. Since scripts do not "exit", all data stays in memory. If you depend on something to be empty, or filled from the results of previous code, declaring my $variable=""; in the early part of your code will clear up most data persistence errors.

See the difference between PerlEx and perl.exe? It's not even accurate after changing Ex to exe.