$x = 10;
*y = *x;
$z = \$x;

{
    print "\$x = $x, \$y = $y, \$\$z = $$z \n";
    local $x;
    print "\$x = $x, \$y = $y, \$\$z = $$z \n";
    $x = 20;
    print "\$x = $x, \$y = $y, \$\$z = $$z \n";
}

##</code><code>##

$x = 10, $y = 10, $$z = 10 
$x = , $y = , $$z = 10 
$x = 20, $y = 20, $$z = 10 

##</code><code>##

$x = 10;
*y = *x;
$z = \$x;

{
    print "\$x = $x, \$y = $y, \$\$z = $$z \n";
    $savex = $x;
    print "\$x = $x, \$y = $y, \$\$z = $$z \n";
    $x = 20;
    print "\$x = $x, \$y = $y, \$\$z = $$z \n";
    $x = $savex;
}

##</code><code>##

$x = 10, $y = 10, $$z = 10 
$x = 10, $y = 10, $$z = 10 
$x = 20, $y = 20, $$z = 20 

##</code><code>##

$x = 10;
*y = *x;
$z = \$x;

foreach $x (1..3) {
    print "\$x = $x, \$y = $y, \$\$z = $$z \n";
}

##</code><code>##

$x = 1, $y = 1, $$z = 10 
$x = 2, $y = 2, $$z = 10 
$x = 3, $y = 3, $$z = 10