Tie::Cycle is a simple module that implements cyclic arrays through a tied reference (to the array):

use strict;
use warnings;
use Tie::Cycle;

my @names = qw/tom harry diana nick sally henry/;
tie my $cycle, 'Tie::Cycle', [
                              sub{print "$_[0] plays\n"},
                              sub{print "$_[0] eats\n"},
                              sub{print "$_[0] sleeps\n"}
                             ];

$cycle && $cycle->($_) for (@names);

[download]

Prints:

tom plays
harry eats
diana sleeps
nick plays
sally eats
henry sleeps

[download]

The last line ($cycle && $cycle->($_) for (@names);) seems a bit odd, but $cycle->($_) doesn't trigger the FETCH sub in the tied scalar (anybody knows why?) and a first call to $cycle is needed.

citromatik

In reply to Re: Implementing a cyclic array by citromatik
in thread Implementing a cyclic array by perlpal

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