#!/usr/bin/perl
use strict;
use warnings;

sub outer {
    my ($x) = @_;

    sub inner {
        return $x + 1
    }
    return inner()
}

print outer(12), "\n";  # 13
print outer(42), "\n";  # 13 !!

##</code><code>##

Variable "$x" will not stay shared at 1.pl line 9.