use threads;
use threads::shared;

use strict;
use warnings;

my @level = (
'ABCDEFGHI',
'12434567',
'+-+-+-+-+-'
);

my @twoDee : shared = ();
foreach (@level)
{
#
#    inner array must be shared to assign its ref
#    to the outer array
#
    my @tempArray : shared = split //;
    push @twoDee, \@tempArray;
}

print join(', ', @$_), "\n"
    foreach (@twoDee);
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