#!/usr/bin/perl -w
    use strict;
    use Tie::Cycle;
    tie my $cycle, 'Tie::Cycle', [0,1,2,3];
    for(1..7){
        print $cycle, " ";
    }
    # printed thus far: 0 1 2 3 0 1 2
    print "\n", '-' x 10, "\n";

    # logical OR returns left expression if TRUE otherwise right
    # expression:

    my ($x,$y) = (0,42);
    my $z;
    $z = $x || $y;
    print "\$z is $z\n";   # prints: $z is 42 (as expected)
    $z = $y || $x;
    print "\$z is $z\n";   # prints: $z is 42 (as expected)
    print '-' x 10,"\n";

    # next use of $cycle should get 3:

    my $ook = $cycle || 42;
    print "\$ook is $ook\n";     # prints: $ook is 0