Hello Veltro,

You are right my example was not clear if I do not add the following part:

#!/usr/bin/perl
use strict;
use warnings;
use Data::Dumper;
use feature 'say';

my @array;
$array[0] = undef; # Assigns the value 'undef' to $array[0]
$array[3] = 2;
# print Dumper \@array;

for my $value (@array) {
    say "Defined: \$array[$value]" if defined $value;
}

__END__

$ perl test.pl 
Defined: $array[2]
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The reason that this is happening is explained in the documentation exists:

Given an expression that specifies an element of a hash, returns true 
+if the specified element in the hash has ever been initialized, even 
+if the corresponding value is undefined.
[download]

So if you check the array element with exists and you have manually defined undef to the element then exists will return True. :)

Thanks for pointing it out. Hopefully it will avoid confusion for future reference. :)

BR / Thanos