...but I ca'nt quite see how it ended up cross-referencing to another array.
Let me repeat, it is because you are storing references. If you want copies, use Storable qw(dclone); Observe 
my $ref = [ 1,2];
my $another = [3,4];
my @foo = ( $ref, $another);
my @bar = $foo[1];

die $bar[0][1];
__END__
4 at - line 6.

[download]
get it?

In reply to Re^3: Updating 1 array affects the other array by Anonymous Monk
in thread Updating 1 array affects the other array by iphony

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