Foo.pm
------
use strict;
use warnings;
sub init {
print("Setting \$Foo::bar to 42.\n");
$Foo::bar = 42;
}
local $Foo::bar;
init();
1;
####
main.pl
-------
use strict;
use warnings;
use Foo ();
print("\$Foo::bar = $Foo::bar\n");
####
output
------
Setting $Foo::bar to 42.
Use of uninitialized value in concatenation (.) or string at main.pl line 7.
$Foo::bar =