1) don't do that, 2) don't do that 3) Read Tutorials: Variable Scoping in Perl: the basics, Coping with Scoping 4) Read Re: Recommendation for dynamically "using" modules (export import into) 5) Read PERL5LIB, PERL5OPT , Re^2: How do I tell CPAN to use a local lib? (perllib/perl5lib/perl5opt/-Idirectory/-Mblib/sitecustomize.pl ) 6) File::FindLib,FindBin, %ENV

$ perl -E " $foo = 1; my $bar = 2; BEGIN{ say -WHAT,$foo,$bar; } say $
+foo,$bar; "
-WHAT
12

$ perl -wE " $foo = 1; my $bar = 2; BEGIN{ say -WHAT,$foo,$bar; } say 
+$foo,$bar; "
Use of uninitialized value $foo in say at -e line 1.
Use of uninitialized value $bar in say at -e line 1.
-WHAT
12

$ perl -wE " my $bar; BEGIN{$foo = 1; $bar = 2;} BEGIN{ say -WHAT,$foo
+,$bar; } say $foo,$bar; "
-WHAT12
12
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use happens at BEGIN time, lexicals(my variables) have no value at BEGIN time, lexicals(my) get initialized after BEGIN

But like I said, don't do that