First of all, in this piece of code, $y doesn't have anything to do with $x because it's single quoted, so $y contains a string which looks like $x

You might want to ref:

my $x = 1;
my $y = \$x;

$$y++;

print $x;
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Update: It turned out that $y has something to do with $x after all.. my bad. see lemming's post below..