sub foo {
    my $x = "a var in foo()";
    sub bar {
        print "\$x is - [$x]\n";
    }
}
bar();

__output__

$x is - []

##</code><code>##

sub foo {
    my $x = "a var in foo()";
    return sub {
        print "\$x is - [$x]\n";
    }
}
foo()->();

__output__

$x is - [a var in foo()]