I found a description of this at Multi dimensional array emulation. It looks like it is creating a hash key from the list, "1,2,3". This seems like it could be a good way to implement a sparse array. 

use warnings;
use strict;
use Data::Dumper;

my %x; 
$x{1,2,3} = 4; 
print $x{1,2,3}, "\n";

print Dumper(\%x);

__DATA__
4
$VAR1 = {
          '1‡˜2‡˜3' => 4
        };

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In reply to Re^3: Why am I getting Can't use string (<string value>) as an ARRAY ref wile "strict refs" in use by Lotus1
in thread Why am I getting Can't use string (<string value>) as an ARRAY ref wile "strict refs" in use by 5NOMAD7

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