#!/usr/bin/perl --
use strict; 
use warnings;
use Data::Dump qw/ dd / ;
my @f = 0; 
my $fo = \$f[0];
dd\@f;
$$fo++; ## @f is updated
dd\@f;
@f=(); ## $fo no longer points to @f, $fo and @f disconnected
$$fo++;
dd\@f;
__END__
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