use strict;
use warnings;
package Foo::Bar;
package main;
my $p = Foo::Bar::;
print "$p\n";         # prints Foo::Bar
my $q = Baz::Qux::;   # warns:
# Bareword "Baz::Qux::" refers to nonexistent package
print "$q\n";         # prints Baz::Qux