FAQ 4.47 How do I handle circular lists?

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4.47: How do I handle circular lists?

    Circular lists could be handled in the traditional fashion with linked
    lists, or you could just do something like this with an array:

            unshift(@array, pop(@array));  # the last shall be first
            push(@array, shift(@array));   # and vice versa

    You can also use "Tie::Cycle":

            use Tie::Cycle;

            tie my $cycle, 'Tie::Cycle', [ qw( FFFFFF 000000 FFFF00 ) ];

            print $cycle; # FFFFFF
            print $cycle; # 000000
            print $cycle; # FFFF00


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